Congenital Anomalies of the Lower Extremity

This chapter describes congenital anomalies of the foot and lower extremity. Congenital anomalies of the hip and pelvis are described in Chapter 30 , and congenital anomalies of the trunk and upper extremities are described in Chapter 31 . Congenital anomalies of the spine are discussed in Chapters 43 and 44 , and congenital anomalies of the hand are discussed in Chapter 80 . Many of the operative techniques described here are useful for other conditions and are found in the references in other chapters.

Anomalies of the Toes

The most common anomaly of the toes is polydactyly, the presence of supernumerary digits. Others are syndactyly (webbed toes), macrodactyly (enlarged toes), and congenital contracture or angulation. Any of these conditions may require surgery. When surgery is contemplated for anomalies of the toes, several factors must be considered, including cosmesis, pain, and difficulty in fitting shoes, but overall long-term function of the foot is the primary concern. A satisfactory clinical result should correct all of these problems.

Polydactyly

Polydactyly of the toes may occur in established genetic syndromes but occurs most commonly as an isolated trait with an autosomal dominant inheritance pattern and variable expression. The overall incidence of polydactyly is approximately two cases per 1000 live births. Surgical treatment of polydactyly is amputation of the accessory digit. Preoperative radiographs should be obtained to detect any extra metatarsal articulating with the digit, which should be amputated with its associated digit ( Fig. 29.1 ). Occasionally, a combined polydactyly-syndactyly deformity requires more complex surgical correction ( Fig. 29.2 ), such as resection of the more peripheral digit using residual skin for coverage.

FIGURE 29.2, Complex polydactyly-syndactyly of left fifth toe with bony and soft-tissue syndactyly.

Venn-Watson classified polydactyly and directed attention to the difference between preaxial and postaxial types ( Fig. 29.3 ). In preaxial polydactyly, the most medial great toe usually is excised. The remaining great toe should have a careful repair of the capsule if necessary to prevent a progressive hallux varus; Kirschner wire fixation can be used for stability if needed for 4 to 6 weeks. A more recent classification system by Seok et al. focuses on the importance of associated syndactylism, axis deviation, and metatarsal extension, with each of these factors resulting in a higher rate of unsatisfactory results after surgical correction. Good results can be expected regardless of the age at which the amputation is performed; however, most supernumerary digits are excised when the child is between 6 and 18 months of age.

FIGURE 29.3, Venn-Watson classification of polydactyly. A, Preaxial polydactyly. B, Postaxial polydactyly.

Amputation of an Extra Toe (Simple Postaxial Polydactyly)

Technique 29.1

▪
At the base of the toe to be amputated, make an oval or racquet-shaped incision through the skin and fascia, preserving extra skin to ensure tension-free closure after amputation of the extra digit ( Fig. 29.4 ).
▪
Draw the tendons distally as far as possible and divide them.
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Incise the capsule of the metatarsophalangeal joint transversely, dissect it from the metatarsal, and disarticulate the joint.
▪
With an osteotome or bone-cutting forceps, sharply resect any bone that may have protruded from the metatarsal head.
▪
If the radiograph has revealed an extra metatarsal, resect it after continuing the incision proximally on the dorsolateral aspect of the foot. A complete extra ray amputation may require transfer of the peroneus brevis tendon insertion with partial resection of the lateral border of the cartilaginous cuboid.

Syndactyly

Syndactyly of the toes rarely interferes with function . The same technique is used as for the fingers (see Chapter 80 ). Syndactyly is commonly associated with polydactyly in the foot, and removal of the more medial or lateral digit is typically preferred.

Macrodactyly

Macrodactyly occurs when one or more toes or fingers have hypertrophied and are significantly larger than the surrounding toes or fingers. The most common associated conditions are neurofibromatosis, hemangiomatosis, and congenital lipofibromatosis. Surgery is indicated to relieve functional symptoms, primarily pain or difficulty in fitting shoes. The cosmetic goal is to alter the abnormal appearance of the toes and foot and to achieve a foot similar in size to the opposite foot ( Fig. 29.5 ).

Many operative procedures have been described for the treatment of macrodactyly, including reduction syndactyly, soft-tissue debulking combined with ostectomy or epiphysiodesis, toe amputation, and ray amputation. Soft-tissue debulking combined with ostectomy or epiphysiodesis can be used in the initial treatment of a single digit with macrodactyly; the recurrence rate with this technique is virtually 100%. Ray resection, combined with debulking repeated as necessary has been recommended; however, when the great toe is involved, the result often is only fair, and repeated soft-tissue debulking may be necessary. When enlargement of the toe or forefoot is less severe, epiphysiodesis of the phalangeal physes is recommended when the toe reaches adult size; debulking is repeated as necessary. Ray amputation is indicated in patients with massive enlargement of the bone and soft tissues and is also the procedure of choice for severe recurrence after reduction syndactyly or soft-tissue debulking. Hallux valgus may occur after resection of the second ray and occasionally requires surgical correction during adolescence.

Tsuge Ray Reduction

The Tsuge procedure is an additional option for pedal macrodactyly treatment. It is a rare procedure for a rare condition; however, according to the authors, the benefit of this procedure is that it debulks and shortens the toe but maintains good cosmesis by preserving the toenail.

Technique 29.2

(TSUGE)

▪
After administering general anesthesia and placing a tourniquet, make a midaxial fish-mouth incision ( Fig. 29.6A ).
▪
Dissect sharply down the plantar aspect of the distal and middle phalanges.
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Disarticulate the distal interphalangeal joint.
▪
Identify and protect the neurovascular bundles within the dorsal flap. Do not excise or debulk.
▪
Release the flexor digitorum longus and extensor digitorum longus tendon insertions from the distal phalanx and tag these (maintain and protect the extensor digitorum longus attachment to the middle phalanx).
▪
Using a microsagittal saw, make a coronal cut along the distal phalanx, excising the plantar portion and leaving approximately a third of the phalanx beneath the nail plate and matrix ( Fig. 29.6B ).
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Make a transverse cut across the distal phalanx, excising the physis ( Fig. 29.6C ).
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Skeletonize the middle phalanx dorsally, protecting the extensor attachment.
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Make a similar size-matched coronal cut in the middle phalanx at the one third dorsal to two thirds plantar level.
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Create a transverse osteotomy across the dorsal aspect of the middle phalanx, leaving the physis still attached to the plantar aspect of the residual bone.
▪
Excise the distal aspect of the dorsal middle phalanx ( Fig. 29.6D ).
▪
Shorten the remaining plantar aspect of the middle phalanx if needed to the desired length of the toe.
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Bring the dorsal sliver of the distal phalanx, which contains the nail, proximally and fit it to the plantar portion of the middle phalanx ( Fig. 29.6E ) and secure the transferred bone with a small Kirschner wire or suture lasso.
▪
Reattach the flexor digitorum longus tendon to the remaining middle phalanx using Vicryl suture (Ethicon, Somerville, NJ). Reattach the extensor digitorum longus tendon to the middle phalanx.
▪
Deflate the tourniquet and obtain hemostasis using bipolar electrocautery.
▪
After the bony work, debulk any redundant plantar flap of tissue and fat ( Fig. 29.6F ) to allow wound closure ( Fig. 29.6G ).
▪
Copiously irrigate the wound and close with absorbable suture. As a result of the digital shortening, a dorsal bump just proximal to the nail is created.
▪
Apply a sterile dressing and a well-padded short leg walking cast.

Postoperative Care

The patient is allowed weight bearing as tolerated.

Ray Reduction

Technique 29.3

▪
Outline dorsal skin incisions along the ray to be reduced, with a single long incision or multiple small incisions along the metatarsal and phalanges.
▪
Debulk any fibrofatty tissue, protecting the digital neurovascular bundles.
▪
Osteotomize the metatarsal neck and shorten the metatarsal by removing a segment of sufficient length to match this metatarsal to the others.
▪
Fuse the physis at the level of the metatarsal head. If necessary, repeat this process for any phalanges until the ray has been shortened to normal length.
▪
Insert a smooth, longitudinal Kirschner wire from the tip of the toe to the base of the metatarsal to align the ray.
▪
Secure hemostasis, close the wound with interrupted sutures, and apply a short leg cast.

Postoperative Care

The Kirschner wire is removed at 6 weeks, and a short leg walking cast is worn until any bony procedures have healed.

Ray Amputation

Technique 29.4

▪
Outline the ray to be amputated with skin flaps to include amputation from the tip of the toe to the base of the metatarsal.
▪
Make dorsal and plantar incisions starting over the metatarsophalangeal joint, with connecting incisions in the web space of adjacent toes. Continue the incisions proximally, dorsally, and plantarward, to the base of the metatarsal to be resected ( Fig. 29.7 ).
▪
Amputate the metatarsal and its associated phalanges and any surrounding hypertrophied soft tissue. Protect the neurovascular bundles that supply adjacent toes.
▪
After adequate resection of tissue, close the wound with interrupted sutures in the usual manner.

Postoperative Care

A short leg cast is applied to protect the wound until healing occurs at 4 to 6 weeks.

Cleft foot (partial adactyly)

Cleft foot (lobster foot) is an anomaly in which a single cleft extends proximally into the foot, sometimes as far as the midfoot. Generally, one or more toes and parts of their metatarsals are absent, and often the tarsals are abnormal. Although the deformity varies in degree and type, the first and fifth rays are usually present ( Fig. 29.8 ). If a metatarsal is partially or completely absent, its respective toe is always absent. Blauth and Borisch classified the deformities into six types based on the number of metatarsal bones present. Type I and type II are cleft feet with minor deficiencies, both having five metatarsals. The metatarsals are normal in type I and partially hypoplastic in type II. The number of identifiable metatarsals decreases progressively: type III, four metatarsals; type IV, three metatarsals; type V, two metatarsals; and type VI, one metatarsal.

FIGURE 29.8, A, Bilateral cleft foot in 4-year-old boy. B, Anteroposterior view; note angular deformity of metatarsophalangeal joints of great toe and fifth toe.

Abraham et al. described a simplified clinical classification on which they based treatment recommendations ( Fig. 29.9 ). Type I has a central ray cleft or deficiency (usually second or third rays or both) extending up to the midmetatarsal level without splaying of medial or lateral rays ( Fig. 29.10 ). For this type of cleft foot, they recommended soft-tissue syndactylism with partial hallux valgus correction if needed; however, this type of deformity typically results in little functional limitation and is primarily a cosmetic concern. Type II has a deep cleft up to the tarsal bones with forefoot splaying, for which they recommended soft-tissue syndactylism, with first-ray osteotomy if needed, before age 5 years. Type III is a complete absence of the first through third or fourth rays, for which they did not recommend surgery; Abraham et al. recommended syndactylism for all type II cleft feet in the first 3 years of life while the forefoot is still supple. All of their patients older than 5 years with type II deformities had first ray amputation.

FIGURE 29.9, Clinical classification of cleft foot deformity (see text).

Any surgery for cleft foot should improve function and appearance. When surgical correction is performed, dorsal and plantar flaps are raised from the skin of the apposing surfaces, which are then sutured together ( Fig. 29.11 ). Any bony or joint deformity of the first or fifth ray should be corrected at the time of surgery ( Fig. 29.12 ). This may require capsulotomies and osteotomies of any retained rays. If pin fixation is used for fixation of osteotomies of the phalanges or metatarsals, the pins and short leg cast are removed 6 weeks after surgery, and a short leg walking cast or cast boot may be worn for an additional few weeks.

FIGURE 29.11, Syndactylism of cleft. A-C, Cleft is manually closed, and cleavage area is marked with sterile ink pen on dorsum and sole of foot. D, Skin and some subcutaneous tissue is removed as outlined by ink lines. E, Undermined skin edges are approximated with horizontal mattress sutures.

FIGURE 29.12, Correction of cleft foot. A, Skin incisions along cleft between abnormal rays of foot. B, Artificial syndactyly created after excision of skin cleft, apposition of rays, and osteotomies of metatarsals.

Wood, Peppers, and Shook described a simplified cleft closure using rectangular flaps. According to these authors, this technique is easier than techniques using multiple triangular flaps and produces superior cosmetic results. They recommended correction of the cleft foot at 6 months old because of fewer anesthesia risks, minimal growth deformities, and malleability of the soft tissues.

Simplified Cleft Closure

Technique 29.5

(WOOD, PEPPERS, AND SHOOK)

▪
At least two metatarsals must be present for good cleft closure.
▪
On the lateral side, or fifth ray, raise a rectangular flap, starting from the plantar surface of the foot to the dorsum ( Fig. 29.13A ). This does not include fascia but includes a fairly thick flap with fat.
▪
Exactly opposite this flap on the medial side, or first ray, raise a rectangular flap starting on the dorsum of the foot to the plantar aspect. Repeat this two or three times until the skin of the entire cleft is removed ( Fig. 29.13B ).
▪
At the longest toe, raise a distally based flap for suturing to the adjacent toe to make a wide web.
▪
If the toes spring apart, make a closing wedge osteotomy at the base of each metatarsal to centralize the toes ( Fig. 29.13C ) and stabilize the osteotomies with Kirschner wires ( Fig. 29.13D ).
▪
To stabilize the intermetacarpal distance further and unload tension on the surgical flaps, reconstruct the ligament with local ligamentous tissue, joint capsule, or tendon obtained from the cleft foot or with autograft plantaris tendon or fascia lata.
▪
Close the wound in routine fashion and apply a cast.

Postoperative Care

At 3 weeks, weight bearing in a walking cast is allowed. At 6 weeks, the cast is discontinued, and the Kirschner wires are removed.

Contracture or angulation of the toes

Congenital contracture, angulation, or subluxation of the fifth toe is a fairly common familial deformity, but rarely causes symptoms. The anomaly is rarely disabling, and surgery usually is indicated only to improve function of the foot or make shoe fitting easier. The direction of angulation of the fifth toe determines the operative procedure. Surgical procedures for the correction of an angulated toe include soft-tissue correction alone, soft-tissue correction with proximal phalangectomy, and amputation.

Correction of Angulated Toe

Technique 29.6

▪
Approach the fifth metatarsophalangeal joint through a Z-plasty incision. With the toe held in the corrected position, draw the central limb of the Z-plasty along the band of contracted skin to the fourth web space. Create the proximal and distal limbs of the Z-plasty of equal lengths ( Fig. 29.14 ). Make the angle of the Z-plasty 60 degrees, which allows maximal elongation along the longitudinal axis of the Z-plasty when the limbs are transposed.
▪
Release the extensor digitorum longus tendon of the fifth toe in a long, oblique fashion.
▪
Release the dorsal and medial capsule and place the toe in the corrected position.
▪
Transpose the two limbs of the Z-plasty and suture them with interrupted absorbable sutures.

Butler arthroplasty can be done for correction of a dorsally overriding fifth toe. One complication of Butler arthroplasty is the potential for vascular damage caused by excessive tension on the neurovascular bundle. This complication can be prevented by (1) avoiding any tension on the neurovascular bundle, (2) taking care not to manipulate or exert traction on the toe, and (3) avoiding the use of circumferential taping or rigid splinting.

Arthroplasty of the Fifth Metatarsophalangeal Joint

Technique 29.7

(BUTLER)

▪
After preparing and draping the foot and applying a tourniquet, make a double-racquet incision, with the dorsal handle following the extensor longus tendon and the plantar handle inclined laterally to provide a circumferential incision ( Fig. 29.15A ). For milder deformities, the dorsal limb of the double-racquet incision alone may allow complete correction of the deformity.
▪
To expose the contracted extensor tendon, elevate skin flaps by blunt dissection, protecting the neurovascular bundle ( Fig. 29.15B ).
▪
Transect the extensor tendon to the fifth toe and divide the dorsal aspect of the metatarsophalangeal joint capsule ( Fig. 29.15C ).
▪
The toe should now partially rotate downward and laterally into the correct position. In long-standing deformities, the plantar aspect of the capsule is adherent and prevents full reduction of the proximal phalanx on the metatarsal during derotation of the toe.
▪
If necessary, separate the adherent plantar capsule by blunt dissection and divide it transversely to allow the toe to lie freely in a fully corrected position ( Fig. 29.15D and E ). This may require the second limb of the double-racquet incision originally described.
▪
Close the skin with multiple interrupted sutures and apply a light dressing to the suture line ( Fig. 29.15F and G ).

Postoperative Care

A short leg cast or postoperative surgical shoe may be worn, with a light dressing only over the fifth toe. Protected activity is allowed as tolerated.

Congenital hallux varus

Congenital hallux varus is a deformity in which the great toe is angled medially. The varus deformity of the toe varies in severity from only a few degrees to 90 degrees. The hallux varus can occur at the metatarsophalangeal joint with a normal metatarsal or it can occur in association with other deformities of the medial foot such as bracket epiphysis or preaxial polydactyly.

Typically, congenital hallux varus is unilateral and is associated with one or more of the following: (1) a short, thick first metatarsal; (2) accessory bones or toes; (3) varus deformity of one or more of the four lateral metatarsals; and (4) a firm fibrous band that extends from the medial side of the great toe to the base of the first metatarsal ( Fig. 29.16 ). The explanation for this anomaly is that two great toes originate in utero, but the medial or accessory one fails to develop. Later, the rudimentary medial toe, together with the band of fibrous tissue, acts like a taut bowstring and gradually pulls the more fully developed great toe into a varus position.

FIGURE 29.16, A, Congenital hallux varus of right foot. B, Anteroposterior radiograph; note short first metatarsal and accessory distal phalanx. C, Appearance after surgical correction.

The proper treatment for congenital hallux varus depends on the severity of the deformity and the rigidity of the contracted soft structures. A metatarsal epiphyseal bracket can be treated with physiolysis if performed very early or physiolysis combined with corrective osteotomy if performed later for milder hallux varus ( Fig. 29.17 ). An osteotomy without physiolysis has an increased risk of recurrence, and the use of a bone graft increases the risk of fusing the epiphyseal bracket. A fat graft can be used as interposition material; however, Choo and Mubarak noted that fat attaches poorly to the diaphysis. Several of their patients developed a peripheral bar at the proximal metaphyseal-epiphyseal junction causing recurrent deformity. They recommended using polymethyl methacrylate as interposition material.

FIGURE 29.17, Epiphyseal bracket. A, Foot with preaxial polydactyly had reconstruction. B, Several months later an epiphyseal bracket of the proximal phalanx was noted with early ossification. C, The patient had excision of the hallux bracket. Intraoperative imaging demonstrating two needles at edges of bracket. D, Kirschner wire placed transversely through proximal phalanx. E, Polymethyl methacrylate cement was placed around wire.

The Farmer technique is effective in correcting moderate deformity. The operation of Kelikian et al. is also satisfactory for severe deformity with an excessively short first metatarsal ( Fig. 29.18 ). Each of these procedures is designed to create a syndactyly between the second toe and the hallux to maintain deformity correction. If the deformity is complicated by traumatic arthritis of the metatarsophalangeal joint, arthrodesis of this joint (see Chapter 82 ) is indicated. In rare cases, if the deformity is too severe either to be corrected or to undergo arthrodesis, amputation is indicated.

FIGURE 29.18, Kelikian procedure for congenital hallux varus. A, Preoperative appearance of foot. B, After artificial syndactyly.

Creation of Syndactyly of the Great Toe and Second Toe for Hallux Varus

Technique 29.8

(FARMER)

▪
Raise a broad Y-shaped flap of skin and subcutaneous tissue from the dorsal surface of the web between the first and second toes ( Fig. 29.19 ); base the flap dorsally in the space between the first and second metatarsals and include in it the skin contiguous with the web distally along the two toes for one third of their length.
▪
From the medial edge of the base of the flap, curve the incision medially and slightly distally across the medial aspect of the first metatarsophalangeal joint. Deepen this incision transversely through the medial part of the capsule of the first metatarsophalangeal joint.
▪
Move the great toe laterally against the second toe and create a syndactyly between these two toes by suturing the apposing skin edges together.
▪
A smooth longitudinal Kirschner wire can be inserted from the tip of the great toe into the first metatarsal to align the great toe in a neutral position.
▪
Excise any accessory phalanx or hypertrophic soft tissue from the great toe through a separate dorsomedial incision.
▪
Swing the Y-shaped flap of skin and subcutaneous tissue medially and suture it in place to cover the defect in the skin on the dorsal and medial aspects of the first metatarsophalangeal joint.
▪
In an alternative technique described by Farmer, the Y-shaped flap of skin and subcutaneous tissue is raised from the plantar surface of the foot ( Fig. 29.20 ); the rest of the procedure is the same as already described, with the flap swung medially to cover the defect in the skin at the first metatarsophalangeal joint. Any defect that cannot be closed by the flap either is left open to heal secondarily or is covered by a full-thickness skin graft.

Postoperative Care

The foot is immobilized in a cast. At 6 weeks, the cast and pins are removed, and full activities are allowed.

Congenital metatarsus adductus

Metatarsus adductus, which consists of adduction of the forefoot in relation to the midfoot and hindfoot, is a common anomaly, often causing intoeing in children. It can occur as an isolated anomaly or in association with clubfoot. Among children with metatarsus adductus, 1% to 5% also have developmental dysplasia of the hip or acetabular dysplasia.

Clinically, metatarsus adductus can be classified as mild, moderate, or severe ( Fig. 29.21 ). In the mild form, the forefoot can be clinically abducted to the midline of the foot and beyond. The moderate form has enough flexibility to allow abduction of the forefoot to the midline, but usually not beyond ( Fig. 29.22 ). In rigid metatarsus adductus, the forefoot cannot be abducted at all. There also may be a transverse crease on the medial border of the foot or an enlargement of the web space between the great and second toes. In general, mild metatarsus adductus resolves without treatment. Moderate or severe metatarsus adductus is best treated initially by serial stretching and casting for 6 to 12 weeks, or until the foot is clinically flexible ( Fig. 29.23 ).

FIGURE 29.21, Heel bisector defines relationship of heel to forefoot from left to right: normal (bisecting second and third toes), mild metatarsus adductus (bisecting third toe), moderate metatarsus adductus (bisecting third and fourth toes), and severe metatarsus adductus (bisecting fourth and fifth toes).

FIGURE 29.22, Congenital metatarsus adductus. Moderate deformity.

FIGURE 29.23, Stretching for correction of metatarsus adductus deformity.

Metatarsus adductus may be seen as a residual deformity in patients previously treated surgically or nonsurgically for congenital clubfoot. This residual metatarsus adductus can be rigid, indicating fixed positioning of the forefoot on the midfoot and hindfoot, or it can be dynamic, caused by imbalance of the anterior tibial tendon during gait. The rigidity or flexibility of the forefoot should be determined before undertaking any surgical correction in an older child. Metatarsus adductus, particularly in its milder forms, is often only a cosmetic concern. However, shoe wear may also become an issue as the child ages.

Treatment

In a young child, surgery is not indicated until conservative treatment has failed. When a child passes the appropriate age for serial stretching and casting, surgery becomes a reasonable option. Indications for surgery include pain, objectionable appearance, and difficulty in fitting shoes because of residual forefoot adduction. Numerous soft-tissue and bony procedures have been described for correction of metatarsus adductus. The most reliable involved osteotomies at either the tarsal or metatarsal levels as described below.

Dome-Shaped Osteotomies of Metatarsal Bases

Berman and Gartland recommended dome-shaped osteotomies for all five metatarsal bases for resistant forefoot adduction in children 4 years old and older ( Fig. 29.24 ). For a mature foot with uncorrected metatarsus adductus, or if all of the medial soft-tissue structures are contracted, they recommended a laterally based closing wedge osteotomy through the bases of the metatarsals. Correcting the alignment without shortening the lateral border of the foot can cause excessive tension on the skin on the medial border or on the neurovascular bundle posterior to the medial malleolus. Steinmann pins inserted parallel to the medial and lateral borders of the foot are usually necessary to hold the foot in the corrected position until the osteotomies have healed. Without internal fixation, the soft tissue on the medial side may cause recurrence of deformity.

Technique 29.9

(BERMAN AND GARTLAND)

▪
Approach all five metatarsal bases dorsally. Make two longitudinal dorsal incisions, one between the first and second metatarsals and the other overlying the fourth. Protect the extensor tendons and superficial nerves and preserve the superficial veins as much as possible.
▪
Expose subperiosteally the proximal metaphysis of each metatarsal, and with a small power drill make a dome-shaped osteotomy in each with the apex of the dome proximally ( Fig. 29.25 ). Avoid the physis at the base of the first metatarsal.
▪
If adequate correction cannot be obtained by these osteotomies, resect small wedges of bone based laterally at the osteotomies as needed.
▪
Align the metatarsals and transfix the foot in the corrected position with small, smooth Steinmann pins inserted proximally through the shafts of the first and fifth metatarsals and across the osteotomies in these bones and, if needed, in all five metatarsals. Prevent dorsal or volar angulation and overriding of the fragments.
▪
Before closing the wound, check the placement of the pins, position of the osteotomies, and forefoot alignment by radiographs ( Fig. 29.26 ). The anteroposterior talus–first metatarsal angle should be corrected to 0 to 10 degrees.

Postoperative Care

A short leg cast is applied with the foot in the corrected position. At 6 weeks, the cast and pins are removed, and weight bearing is begun, commonly in a walking cast or cast boot for 2 to 4 weeks.

FIGURE 29.24, A and B, Rigid metatarsus adductus in 8-year-old child. C and D, After multiple metatarsal osteotomies. SEE TECHNIQUE 29.9.

For the osteotomy portion of the above technique, Knorr et al. described using the Cahuzac technique of percutaneous osteotomies of the metatarsals in children with metatarsus adductus. The approach uses a beaver blade to create two small incisions over the base of the second metatarsal and the third intermetatarsal space. A high-speed surgical burr is used to create a percutaneous osteotomy of the second through fourth metatarsal bases. Percutaneous cuneometatarsal capsulotomy is performed with a 19-gauge needle. The forefoot is manipulated and stabilized with an obliquely oriented, percutaneous 2-mm Kirschner wire from the first metatarsal into the tarsal bones.

Cuneiform and Cuboid Osteotomies

McHale and Lenhart recommended opening wedge osteotomy of the medial cuneiform and closing wedge osteotomy of the cuboid for correction of deformities in the midfoot with severe shortening of the medial column (“bean-shaped” foot).

Technique 29.10

(MCHALE AND LENHART)

▪
With the anesthetized patient supine, make a small longitudinal incision over the cuboid ( Fig. 29.27A ).
▪
Remove a 7- to 10-mm wedge with its base in a dorsolateral position ( Fig. 29.27B ).
▪
Approach the medial cuneiform by using part of the distal extension of the medial incision ( Fig. 29.27A ) or a 2-cm incision medially over the medial cuneiform.
▪
Make the osteotomy in the cuneiform, leaving the anterior tibial tendon attached to the distal piece of bone.
▪
Spread the medial cuneiform osteotomy with a smooth spreader and insert the wedge of bone removed from the cuboid, with the base of the wedge straight medially ( Fig. 29.27C ).
▪
Check clinical correction of the deformity. If the lateral border of the foot still appears prominent (midfoot supination has not been corrected), remove a larger wedge of bone from the cuboid.
▪
Use two smooth Kirschner wires to fix the foot in the corrected position. Insert one pin through the cuboid, starting in the calcaneus and exiting through the base of the fifth metatarsal. Place the other pin through the first web space, through the medial cuneiform and tarsal navicular, and into the talus.
▪
Confirm the position of the pins and the correction of the bony deformity with radiographs.
▪
After correct positioning of the foot, the lateral three toes may remain in passively uncorrectable flexion. If so, perform simple flexor tenotomy.
▪
Close the wounds and apply a short leg cast with thick padding to allow for swelling.

Postoperative Care

At 2 weeks, the wounds are checked, and a more form-fitting, non–weight-bearing cast is applied. The pins are removed at 6 weeks, and a weight-bearing cast is applied. A cast or cast boot is worn until bony union is evident on radiographs, usually at 8 to 12 weeks.

Anomalies of the Foot

Congenital clubfoot (talipes equinovarus)

The incidence of congenital clubfoot is approximately 1 in every 1000 live births. Although most cases are sporadic occurrences, families have been reported with clubfoot as an autosomal dominant trait with incomplete penetrance. Bilateral deformities occur in 50% of patients. In patients with bilateral deformity, the severity and response to treatment is highly correlated between the 2 feet.

Several theories have been proposed regarding the cause of clubfoot, but the underlying cause of clubfoot is still mostly unknown. One theory is that a primary germplasm defect in the talus causes continued plantarflexion and inversion of this bone, with subsequent soft-tissue changes in the joints and musculotendinous complexes. Another theory is that primary soft-tissue abnormalities within the neuromuscular units cause secondary bony changes. There may be a vascular cause because many children with clubfoot have a hypertrophic anterior tibial artery or other vascular anomalies. Several authors have documented abnormal distribution of type I and type II muscle fibers in clubfeet. While the exact cause remains unknown, a number of factors have been correlated with a higher frequency of clubfoot, including maternal and paternal smoking, maternal obesity, family history, amniocentesis, and some selective serotonin reuptake inhibitors.

Multiple studies have demonstrated no correlation between clubfoot and developmental dysplasia of the hip. It is thought that a routine clinical examination screening is all that is needed for the evaluation of hip pathology in children born with a clubfoot deformity.

The pathologic changes caused by congenital clubfoot must be understood if the anomaly is to be treated effectively. The four basic components of clubfoot are cavus, adduction, varus, and equinus. The deformity varies in severity, from a mild positional clubfoot that is passively correctable to near the neutral position to a much more severe clubfoot with extreme, rigid hindfoot equinus and forefoot adduction. The typical deformity is shown in Fig. 29.28 . Clubfoot often is accompanied by internal tibial torsion. The ankle, midtarsal, and subtalar joints all are involved in the pathologic process. In unilateral cases, the abnormal foot may be one half to one size smaller in length and width.

FIGURE 29.28, Congenital clubfoot in newborn. Posterior view—inversion, plantarflexion, and internal rotation of calcaneus and cavus deformity with transverse plantar crease.

Turco attributed the deformity to medial displacement of the navicular and calcaneus around the talus. The talus is forced into equinus by the underlying calcaneus and navicular, whereas the head and neck of the talus are deviated medially. From a three-dimensional perspective, the relationship of the calcaneus to the talus is characterized by abnormal rotation in the sagittal, coronal, and horizontal planes. As the calcaneus rotates horizontally while pivoting on the interosseous ligament, it slips beneath the head and neck of the talus anterior to the ankle joint, and the calcaneal tuberosity moves toward the fibular malleolus posteriorly. The proximity of the calcaneus to the fibula is primarily caused by horizontal rotation of the talocalcaneal joint, rather than by equinus alone. The heel appears to be in varus because the calcaneus rotates through the talocalcaneal joint in a coronal plane and horizontally. The talonavicular joint is in an extreme position of inversion as the navicular moves around the head of the talus. The cuboid is displaced medially on the calcaneus.

In a three-dimensional clubfoot computer model, the talar neck has been shown to be internally rotated relative to the ankle mortise, but the talar body is externally rotated in the mortise. The calcaneus is significantly internally rotated with the sloped articular facet of the calcaneocuboid joint causing additional internal rotation of the midfoot.

Contractures or anomalies of the soft tissues exert further deforming forces and resist correction of bony deformity and realignment of the joints. Talocalcaneal joint realignment is opposed by the calcaneofibular ligament, the superior peroneal retinaculum (calcaneal fibular retinaculum), the peroneal tendon sheaths, and the posterior talocalcaneal ligament. Resisting realignment of the talonavicular joint are the posterior tibial tendon, the deltoid ligament (tibial navicular), the calcaneonavicular ligament (spring ligament), the entire talonavicular capsule, the dorsal talonavicular ligament, the bifurcated (Y) ligament, the inferior extensor retinaculum, and occasionally the cubonavicular oblique ligament. Internal rotation of the calcaneocuboid joint causes contracture of the bifurcated (Y) ligament, the long plantar ligament, the plantar calcaneocuboid ligament, the navicular cuboid ligament, the inferior extensor retinaculum (cruciate ligament), the dorsal calcaneocuboid ligament, and occasionally the cubonavicular ligament.

The metatarsals also are often deformed. They may deviate at the tarsometatarsal joints, or these joints may be normal, and the shafts of the metatarsals themselves may be adducted.

If the clubfoot is allowed to remain deformed, many other late adaptive changes occur in the bones. These changes depend on the severity of the soft-tissue contractures and the effects of walking. In untreated adults, some joints may spontaneously fuse, or they may develop degenerative changes secondary to the contractures. The untreated clubfoot is cosmetically, functionally, and psychologically unacceptable. Every effort should be made to correct the deformity.

The initial examination of the foot and the progress of treatment should depend on clinical judgment and occasionally radiographic examination.

Radiographic evaluation

If the clubfoot deformity is somewhat atypical, is associated with a global genetic or neurologic condition, or appears resistant to initial nonoperative treatment, imaging evaluation should be included. In a nonambulatory child, standard radiographs include simulated weight-bearing anteroposterior and stress dorsiflexion lateral radiographs of both feet. Standing anteroposterior and lateral standing radiographs may be obtained for an older child. Alternatively, ultrasonography has been proposed as a radiation-free imaging modality and could be used in locations familiar with the technique.

Important angles to consider in the evaluation of clubfoot are the talocalcaneal angle on the anteroposterior radiograph and, on the lateral radiograph, the talocalcaneal angle, the tibiocalcaneal angle, and the talus–first metatarsal angle ( Fig. 29.29 ). The anteroposterior talocalcaneal angle in normal children ranges from 30 to 55 degrees ( Table 29.1 ). In clubfoot, this angle progressively decreases with increasing heel varus. On the dorsiflexion lateral radiograph, the talocalcaneal angle in a normal foot varies from 25 to 50 degrees; in clubfoot, this angle progressively decreases with the severity of the deformity to an angle of 0 degrees, or parallelism. The tibiocalcaneal angle in a normal foot is 10 to 40 degrees on the stress lateral radiograph. In clubfoot, this angle generally is negative, indicating equinus of the calcaneus in relation to the tibia. Finally, the talus–first metatarsal angle is a radiographic measurement of forefoot adduction. This is useful in the treatment of metatarsus adductus alone but is equally important in the treatment of clubfoot to evaluate the position of the forefoot. In a normal foot, this angle is 5 to 15 degrees on the anteroposterior view; in clubfoot, it usually is negative, indicating adduction of the forefoot.

FIGURE 29.29, Radiographic evaluation of clubfoot. A, Anteroposterior view of right clubfoot with decrease in talocalcaneal angle and negative talus–first metatarsal angle. B, Talocalcaneal angle on anteroposterior view of normal left foot. C, Talocalcaneal angle of 0 degrees and negative tibiocalcaneal angle on dorsiflexion lateral view of right clubfoot. D, Talocalcaneal and tibiocalcaneal angles on dorsiflexion lateral view of normal left foot.

TABLE 29.1

Progression of Foot Angles in Normal Feet Over Average 6-Year Follow-Up

Angle	Average	Average
	First Visit	Last Visit
	(Degrees)	(Degrees)
Anteroposterior View
Talocalcaneal	36.3	27.4
Calcaneal–second metatarsal	14.4	12.3
Talus–first metatarsal	16.9	8.1
Lateral View
Talocalcaneal	46	44.2
Calcaneal–first metatarsal	150	148
Tibiocalcaneal	61.5	73.2
Talus–first metatarsal	16.3	12.1
Talocalcaneal index	83	71.6

Classification

Two of the more commonly used classifications by Pirani et al. and Diméglio et al. are based solely on physical examination requiring no radiographic measurements or other special studies. Pirani’s system is composed of six different physical examination findings and includes a hindfoot contracture score and a midfoot contracture score, each scored 0 for no abnormality, 0.5 for moderate abnormality, or 1 for severe abnormality. Each foot is assigned a total score, the maximum being 6 points, with a higher score indicating a more severe deformity. In the system of Diméglio et al., four parameters are assessed on the basis of their reducibility with gentle manipulation as measured with a handheld goniometer: (1) equinus deviation in the sagittal plane, (2) varus deviation in the frontal plane, (3) derotation of the calcaneopedal block in the horizontal plane, and (4) adduction of the forefoot relative to the hindfoot in the horizontal plane ( Fig. 29.30 ). One additional point is given for each of the following: a posterior skin crease, a medial skin crease, rigid cavus, and poor muscle condition. In a comparison of the two systems, both were shown to have good interobserver reliability after the initial learning phase. Routine clinical use of one or both of these classification systems can be helpful in determining prognosis and documenting maintenance of correction or recurrence over time.

Nonoperative treatment

The initial treatment of clubfoot is nonoperative. Various treatment regimens have been proposed, including the use of corrective splinting, taping, and casting. Although a number of various casting techniques are used, the most widely accepted technique is that described by Ignacio Ponseti and consists of weekly serial manipulation and casting during the first weeks of life.

Ponseti Casting Technique for Correction of Clubfoot Deformity

Successful correction of clubfoot deformity generally is reported in more than 90% of children 2 years and younger treated with Ponseti casting even after previous unsuccessful nonoperative treatment. Multiple studies have highlighted the success and reproducibility of the Ponseti method even in developing nations. Achilles tenotomy generally is required, and anterior tibial tendon transfer may be added to the casting routine when necessary. Bleeding complications have been reported after percutaneous tenotomy from injury to the peroneal artery or the lesser saphenous vein; making a small open incision directly over the tendon before severing it, making the tenotomy from medial to lateral ( Fig. 29.31 ) , and using a more rounded beaver-eye blade can help avoid vascular injury.

FIGURE 29.31, Technique of percutaneous Achilles tenotomy from medial to lateral; note proximity of peroneal artery, lesser saphenous vein, and sural nerve to lateral edge of tendon.

Reported recurrence rates after Ponseti casting range from 10% to 30%; however, many recurrent deformities can be treated successfully with repeat casting, with or without the addition of Achilles tenotomy or anterior tibial tendon transfer. Numerous authors have noted that the most important factor in avoiding recurrent deformity is patient compliance with the postoperative brace wear regimen. Although the Ponseti method is ideally used in newborns, many studies have demonstrated successful use of the Ponseti method in older children or children with recurrent deformities after initial casting treatment. Also, the reported recurrence rates are higher in studies of children with syndrome-associated clubfoot deformities than in children with idiopathic clubfeet. Although the success rates are lower in older children and in those with syndromic clubfeet, nonoperative treatment should still be considered the first line of treatment even in these more challenging situations.

Strict adherence to the principles described by Ponseti is important to achieve optimal results. Only a few modifications to his original technique have demonstrated equivalent results. An accelerated casting program biweekly can result in more rapid correction of the deformity without compromising outcome. Fiberglass casting material has been shown to provide similar results to plaster casts. Bracing up to the age of 4 years may be superior to discontinuing brace treatment at the age of 3 years as originally described.

Application of Ponseti Casts

The Ponseti method consists of two phases: treatment and maintenance. The treatment phase should begin as early as possible, optimally within the first 2 weeks of life; however, older children also can be treated nonoperatively using Ponseti’s principles. Gentle manipulation and casting are done weekly, although more frequent cast changes over a shorter period of time have been advocated by some authors. The order of correction by serial manipulation and casting should be as follows: first, correction of forefoot cavus and adduction; next, correction of heel varus; and finally, correction of hindfoot equinus. Correction should be pursued in this order so that a rocker-bottom deformity is prevented by dorsiflexing the foot through the ankle joint rather than the midfoot. Each cast holds the foot in the corrected position, allowing it to reshape gradually. Generally, five to six casts are required to correct the alignment of the foot and ankle fully. Before application of the final cast, most infants require percutaneous Achilles tenotomy to gain adequate lengthening of the Achilles tendon and prevent a rocker bottom deformity.

The first cast application corrects the cavus deformity by aligning the forefoot with the hindfoot, supinating the forefoot to bring it in line with the heel, and elevating (dorsiflexing) the first metatarsal ( Fig. 29.32A ). The casts should be applied in two stages: first, a short leg cast to just below the knee, then extension above the knee when the plaster sets. Long leg casts are essential to maintain a strong external rotation force of the foot beneath the talus, to allow adequate stretching of the medial structures, and to prevent cast slippage.

FIGURE 29.32, Technique of Ponseti casting for clubfoot correction (see text). A, First cast; note positioning of forefoot to align with heel, with outer edge of foot tilted even farther downward because of Achilles tendon tightness. B, Second cast is applied with outer edge of foot still tilted downward and forefoot moved slightly outward. C, Third cast; Achilles tendon is stretched bringing outer edge of foot into more normal position as forefoot is turned farther outward. D, Final cast; Achilles tendon is stretched more with foot pointed upward.

One week after application, the first cast is removed, and after about 1 minute of manipulation, the next toe-to-groin cast is applied ( Fig. 29.32B ). Manipulation and casting at this stage are focused on abducting the foot around the head of the talus, with care to maintain the supinated position of the forefoot and avoid any pronation. During these manipulations, the navicular can be felt reducing over the talar head by a thumb placed on the head of the talus. It is crucial that forefoot derotation occur about the talus rather than the calcaneocuboid joint, and the heel should not be directly manipulated. Maintaining forefoot supination throughout the process and correcting the talonavicular subluxation without producing a rocker-bottom deformity will cause the calcaneus to abduct and evert. Final correction of residual calcaneus deformity can then be achieved with a percutaneous Achilles tenotomy.

Manipulation and casting are continued weekly for the next 2 to 3 weeks to abduct the foot gradually around the head of the talus. The foot should never be actively pronated; however, the amount of supination is gradually decreased over these several casts until the forefoot is in neutral position relative to the longitudinal axis of the foot ( Fig. 29.32C ). Ideally, each cast should be removed just before repeat manipulation and casting, and a variety of casting materials can be used with similar success.

The final cast is applied with the foot in the same maximally abducted position and dorsiflexed 15 degrees. In most children, a percutaneous Achilles tenotomy is done to prevent development of a rocker-bottom deformity. This procedure can either be performed in the clinic with local skin anesthesia, or in the operating room under sedation or general anesthesia. The benefit of tenotomy in the clinic setting is a reduced need for anesthesia and prolonged fasting; however, the operating room offers the ability to more easily control any excess bleeding that may occur. The foot is casted in the final position of approximately 70 degrees of abduction and 15 degrees of dorsiflexion for 3 weeks ( Fig. 29.32D ). Five or six casts usually are necessary to correct the clubfoot deformity (see ) .

Maintenance Phase

When the final cast is removed, the infant is placed in a brace that maintains the foot in its corrected position (abducted and dorsiflexed). The brace (foot abduction orthosis) consists of shoes mounted to a bar in a position of 70 degrees of external rotation and 15 degrees of dorsiflexion. The distance between the shoes is set at about 1 inch wider than the width of the infant’s shoulders ( Fig. 29.33 ).

FIGURE 29.33, Foot abduction orthosis consists of shoes mounted to bar in 70 degrees external rotation and 15 degrees dorsiflexion.

Multiple different types of shoes and bars have been designed and proposed. In some cases, it may be necessary to experiment with different combinations to find a brace that will lead to maximal compliance. The brace is worn 23 hours each day for the first 3 months after casting and then while sleeping for 3 to 4 years. Brace wear compliance is of upmost importance in maintaining correction and preventing recurrence. Frequent follow-up during the bracing period is essential to encourage continued compliance and to detect early recurrence.

Management of Recurrence

Recurrence of the deformity is infrequent if the bracing protocol is followed closely. Early recurrences (usually mild equinus and heel varus) are best treated with repeat manipulation and casting. The first cast may require some dorsiflexion of the first ray if cavus deformity is present. Subsequent casts abduct the foot around the talar head, correcting the varus and ultimately allowing ankle dorsiflexion. Achilles tendon lengthening may be necessary if dorsiflexion is insufficient; transfer of the anterior tibial tendon may be necessary to help maintain correction, particularly in children with persistent dynamic inversion.

Anterior Tibial Tendon Transfer

Technique 29.11

▪
Begin the anterior tibial tendon transfer only if adequate ankle dorsiflexion is present or has been obtained by a lengthening of the gastroc-soleus-Achilles complex (see Technique 33.13).
▪
Make a small 1- to 2-cm incision directly over the insertion of the anterior tibial tendon on the dorsomedial aspect of the foot.
▪
Open the tendon sheath and free the anterior tibial tendon from its insertion sharply, preserving as much length as possible.
▪
The tendon can then be transferred into the lateral cuneiform by one of two techniques. A two-incision technique moves the tendon directly across the dorsum of the foot and results in a change in direction of the tendon pull at the level of the ankle. A three-incision technique reroutes the tendon through a more proximal incision, resulting in a more direct path to the new insertion site, but the three-incision technique requires an additional incision and more surgical dissection.
▪
For the three-incision technique, palpate the anterior tibial tendon over the anterior distal third of the tibia and make a small, 1-cm incision.
▪
Dissect down to the tendon sheath and then open it sharply. Pass a hemostat behind the tendon and pull it firmly into the proximal incision. Some additional dissection may be required from both the proximal and distal wounds to free up the tendon from the sheath.
▪
Close the distal wound in a standard fashion. Closing each wound, once they are no longer needed, avoids the need to maintain prolonged foot dorsiflexion at the end of the case while all wounds are closed.
▪
Using a tendon locking stitch, such as a whipstitch, Krakow stitch, or crossing stitch, secure a number 1 Vicryl suture to the tendon, leaving long ends for transfer.
▪
Identify the location of the lateral cuneiform with image intensification. Make a small, 1- to 2-cm incision over that position. Identify and protect any branches of the superficial peroneal nerve.
▪
Retract the extensor digitorum longus tendons and extensor digitorum muscle belly out of the way of the underlying lateral cuneiform periosteum.
▪
Create a “trapdoor” of periosteum and capsule directly over the lateral cuneiform. Leave the distal portion of this soft-tissue flap intact.
▪
Pass a Kelly clamp from the distal-lateral incision deep to the ankle retinaculum and up to the more proximal incision. Spread the Kelly clamp and make two or three passes to make space for the transferred tendon.
▪
Grasp the tendon sutures with the Kelly clamp and deliver them, along with the tendon, into the distal incision.
▪
Use image intensification to localize the center of the lateral cuneiform. Create a hole in the bone from dorsal to plantar with a trephine similar in size to that of the tendon.
▪
Using two straight Keith needles, pass the two limbs of the suture through the bone hole and out the plantar aspect of the foot. Pass the needles through a piece of sterile felt and through the holes of sterile plastic button.
▪
Have an assistant maintain the foot in a dorsiflexed and everted position. Make sure that the tendon has passed into the trephinated hole in the lateral cuneiform. Secure the suture snuggly against the button.
▪
Replace the bone plug from the trephine into the space adjacent to the tendon using a plunger.
▪
Lay the trapdoor flap against the tendon and secure with a horizontal mattress suture.
▪
Close any remaining wounds and apply a dressing and a short leg cast with the foot in the corrected position.

Postoperative Care

The cast is left on for 6 weeks and then removed in the clinic along with the felt and button.

Operative treatment

Surgery in clubfoot is indicated for deformities that do not respond to conservative treatment by serial manipulation and casting and should be attempted only after all other, less-aggressive means have been exhausted. Often in children with a significant rigid clubfoot deformity, the forefoot has been corrected by conservative treatment, but the hindfoot remains fixed in varus and equinus, or the deformity has recurred. Surgery in the treatment of clubfoot must be tailored to the age of the child and to the deformity to be corrected.

Extensive release that includes the posterolateral ligament complex most often is required for severe deformity. The procedure described by McKay takes into consideration the three-dimensional deformity of the subtalar joint and allows correction of the internal rotational deformity of the calcaneus and release of the contractures of the posterolateral and posteromedial foot. A modified McKay procedure through a transverse circumferential (Cincinnati) incision is our preferred technique for the initial surgical management of most clubfeet. In many cases, a complete exposure of the talonavicular joint medially may not be required because partial correction often can be achieved with initial or repeat casting. This selective approach to soft-tissue release is preferred to lessen postoperative stiffness.

Transverse Circumferential (Cincinnati) Incision

One option for comprehensive release is the use of the transverse circumferential incision, also known as the Cincinnati incision. This incision provides excellent exposure of the subtalar joint and is useful in patients with a severe internal rotational deformity of the calcaneus. One potential problem with this incision is tension on the suture line when attempting to place the foot in dorsiflexion to apply the postoperative cast. To avoid this, the foot can be placed in plantarflexion in the immediate postoperative cast and then in dorsiflexion to the corrected position at the first cast change when the wound has healed at 2 weeks. This cast change frequently requires sedation or outpatient general anesthesia.

If primary skin closure is difficult in a foot in a fully corrected position, a fasciocutaneous flap closure can be used. The rotation of V-Y flaps allow complete wound closure without any skin tension.

Technique 29.12

(CRAWFORD, MARXEN, AND OSTERFELD)

▪
Begin the incision on the medial aspect of the foot in the region of the naviculocuneiform joint ( Fig. 29.34A ).
▪
Carry the incision posteriorly, gently curving beneath the distal end of the medial malleolus and ascending slightly to pass transversely over the Achilles tendon approximately at the level of the tibiotalar joint ( Fig. 29.34B ).
▪
Continue the incision in a gentle curve over the lateral malleolus and end it just distal and slightly medial to the sinus tarsi ( Fig. 29.34C ).
▪
Extend the incision distally medially or laterally, depending on the requirements of the operation.

Extensile Posteromedial and Posterolateral Release

Technique 29.13

(MCKAY, MODIFIED)

▪
Incise the skin through a transverse circumferential (Cincinnati) incision, preserving if possible the veins on the lateral side and protecting the sural nerve.
▪
Dissect the subcutaneous tissue up and down the Achilles tendon to lengthen the tendon at least 2.5 cm in the coronal plane. If sagittal plane lengthening is done, the lateral attachment of the Achilles tendon to the calcaneus should be preserved to aid in correction of hindfoot varus.
▪
Incise the superior peroneal retinaculum off the calcaneus at the point where it blends with the sheath of the Achilles tendon.
▪
Dissecting carefully, release the peroneal tendons from their sheaths and protect them with a vessel loop, then separate the calcaneofibular and posterior calcaneotalar ligaments, the thickened superior peroneal retinaculum, and the peroneal tendon sheath.
▪
Incise the calcaneofibular ligament close to the calcaneus (this ligament is short and thick and attached very close to the apophysis).
▪
Incise the lateral talocalcaneal ligament and the lateral capsule of the talocalcaneal joint from their attachments to the calcaneocuboid joint to the point where they enter the sheath of the flexor hallucis longus tendon posteriorly. In more resistant clubfeet, the origin of the extensor digitorum brevis, cruciate crural ligament (inferior extensor retinaculum), dorsal calcaneocuboid ligament, and, occasionally, cubonavicular oblique ligament must be dissected off the calcaneus to allow the anterior portion of the calcaneus to move laterally.
▪
On the medial side, dissect free the neurovascular bundle (medial and lateral plantar nerves and associated vascular components) into the arch of the foot, preserving the medial calcaneal branch of the lateral plantar nerve. Protect and retract the neurovascular bundle with a small Penrose drain or vessel loop. Complete dissection of the medial and lateral neurovascular bundle throughout the arch of the foot.
▪
Enter the compartment of the medial plantar neurovascular bundle and follow it into the arch of the foot well beyond the cuneiforms; elevate the abductor hallucis muscle to enter the plantar aspect of the foot.
▪
Enter the sheaths of the posterior tibial tendon, the flexor hallucis longus and flexor digitorum longus tendons, and protect each of these structures.
▪
Section the narrow strip of fascia between the medial and lateral branches of the plantar nerve to allow the abductor hallucis to slide distally.
▪
Enter the sheath of the posterior tibial tendon just posterior to and above the medial malleolus. Split the sheath and superficial deltoid ligament up the tibia until the muscle can be identified.
▪
Lengthen the tendon by Z-plasty at least 2.5 cm proximal from the medial malleolus to the maximal distance allowed by the incision. Starting from the point at which the flexor digitorum longus and the flexor hallucis longus tendons cross, sharply dissect both sheaths from the sustentaculum tali, moving in a proximal direction until the talocalcaneal joint is entered.
▪
Continue the dissection down and around the navicular, holding the distal segment of the lengthened posterior tibial tendon attached to the bone.
▪
Open the talonavicular joint by pulling on the remaining posterior tibial tendon attachment and carefully cut the deltoid ligament (medial tibial navicular ligament), talonavicular capsule, dorsal talonavicular ligament, and plantar calcaneonavicular (spring) ligament close to the navicular.
▪
Enter and carefully expose by blunt dissection and retraction the interval between the dorsal aspect of the talonavicular joint and the extensor tendons and neurovascular bundle on the dorsum of the foot. Do not dissect or disturb the blood supply to the dorsal aspect of the talus.
▪
Follow through with the dissection, incising the capsule of the talonavicular joint all the way around medially, inferiorly, superiorly, and laterally. Inferior and lateral to the joint is the bifurcated (Y) ligament; incise both ends of this ligament to correct the horizontal rotation of the calcaneus.
▪
Complete the release of the talocalcaneal joint ligaments and capsule by incising the remaining medial and posteromedial capsule and superficial deltoid ligament attached to the sustentaculum tali. Do not incise the talocalcaneal ligaments (interosseous ligaments) at this time.
▪
Retract the lateral plantar nerve, detach the origin of the quadratus plantae muscle using a periosteal elevator on the medial inferior surface of the calcaneus, and expose the long plantar ligament over the plantar calcaneocuboid ligament and the peroneus longus tendon.
▪
At this point, the talus should roll back into the ankle joint, exposing at least 1.5 cm of hyaline cartilage on its body. If this does not happen, incise the posterior talofibular ligament. If the talus still does not roll back into the ankle joint, cut the posterior portion only of the deep deltoid ligament.
▪
The decision must be made as to the necessity of dividing the interosseous talocalcaneal ligament to correct the horizontal rotational abnormality through the talocalcaneal joint. This decision depends on the completeness of the correction and the mobility of the subtalar complex, as determined by the position of the foot. The interosseous ligament should be preserved intact if at all possible.
▪
Line up the medial side of the head and neck of the talus with the medial side of the cuneiforms and medially push the calcaneus posterior to the ankle joint while pushing the foot as a whole in a posterior direction. Examine the angle made by the intersection of the bimalleolar ankle plane with the horizontal plane of the foot; if the angle is 85 to 90 degrees, the ligament need not be cut. In children older than 1 year of age, such an incision generally is necessary, however, because the ligament usually has become broad and thick, preventing derotation of the talocalcaneal joint.
▪
After the foot has been satisfactorily corrected, pass a small Kirschner wire through the talus from the posterior aspect into the middle of the head. Positioning the pin in a slightly lateral direction in the head of the talus is beneficial in older children with more pronounced medial deviation of the talar head and neck because it allows lateral displacement of the navicular and cuneiforms on the head of the talus to eliminate forefoot adduction.
▪
Pass the pin through the talonavicular joint and cuneiforms and out the forefoot on either the medial or the lateral side of the first metatarsal. While an assistant inserts the pin, mold the forefoot out of adduction. Cut off the end of the pin close to the body of the talus. The pin can be left out of the skin on the dorsum of the forefoot or just under the skin requiring a small incision later for removal in the operating room.
▪
Check for proper positioning of the foot: The longitudinal plane of the foot is 85 to 90 degrees to the bimalleolar ankle plane, and the heel under the tibia is in slight valgus.
▪
If the talocalcaneal ligament has been divided, insert a pin through the calcaneus, burying it deep in the talus from the plantar surface. Do not penetrate the ankle joint.
▪
Suture the posterior tibial and Achilles tendons snugly with the foot in slight dorsiflexion. Lengthening of the flexor digitorum longus is rarely required, but the flexor hallucis longus is typically tight with the foot in the corrected position. The flexor hallucis longus tightness can be corrected by a fractional lengthening at the musculotendinous junction, a Z-lengthening of the tendon, transection of the tendon after formal tenodesis to the flexor digitorum longus at the master knot of Henry (preferred technique), or by flexor tenotomy at the level of proximal phalanx of the great toe.
▪
Reposition the lengthened posterior tibial tendon in its sheath and repair the sheath beneath the medial malleolus. With the fibrofatty tissue left attached to the calcaneus anterior to the Achilles tendon, cover the lateral aspect of the ankle joint. Keep the peroneal tendons and sheaths from subluxating around the fibula by suturing the sheaths of the peroneal tendons to the fibrofatty flap. Close the subcutaneous tissue and skin with interrupted sutures.
▪
Apply nonadherent dressing and, very loosely, apply a padded long leg cast with the foot in plantarflexion and flexed to 90 degrees ( Fig. 29.35 ).

Postoperative Care

A long leg cast is applied with the foot in plantarflexion. At 2 weeks, the cast is changed, and the foot is placed in the corrected position. This can be done with sedation or general anesthesia as an outpatient procedure. At 6 weeks, the cast and pins are removed in the operating room ( Fig. 29.36 ). Correction is maintained in an ankle/foot orthosis.

FIGURE 29.36, A and B, Radiographic appearance of left foot in 6-year-old child who had modified McKay procedures at 6 months of age. SEE TECHNIQUE 29.13.

In addition to complete recurrent deformity, special attention should be given to two specific problems in clubfoot. The first is residual hindfoot equinus in children 6 to 12 months old who have obtained adequate correction of forefoot adduction and hindfoot varus. This equinus can be corrected adequately by Achilles tendon lengthening and posterior capsulotomy of the ankle and subtalar joints without an extensive one-stage posteromedial release. Careful intraoperative assessment is necessary to determine if a more extensive release is required instead of a limited procedure that corrects only hindfoot equinus. The heel varus and internal rotation must have been corrected adequately if Achilles tendon lengthening and posterior capsulotomy are to be used alone.

The second specific problem is dynamic metatarsus adductus and forefoot supination caused by overpull of the anterior tibial tendon in older children who have had correction of clubfoot. In these children, the treatment of choice is transfer of the anterior tibial tendon to the lateral cuneiform. The hindfoot and forefoot must be flexible for a tendon transfer to succeed (see Technique 34.9).

Achilles Tendon Lengthening and Posterior Capsulotomy (Selective Approach)

Technique 29.14

▪
Make a straight longitudinal incision over the medial aspect of the Achilles tendon, beginning at its most distal point and extending proximally to 3 cm above the level of the ankle joint. Carry sharp dissection through the subcutaneous tissue.
▪
Identify the Achilles tendon and make an incision through the peritenon medially. Dissect the Achilles tendon circumferentially to expose it for a length of 3 to 4 cm.
▪
Perform a tenotomy of the plantaris tendon if it is present.
▪
Identify medially the flexor hallucis longus, flexor digitorum communis, and posterior tibial tendons and the neurovascular bundle; protect these with Penrose drains.
▪
Perform a Z-plasty to lengthen the Achilles tendon by releasing the medial half distally and the lateral half proximally for a distance of 2.5 to 4 cm ( Fig. 29.37 ).
▪
Gently debride pericapsular fat at the level of the subtalar joint.
▪
Identify the posterior aspect of the ankle joint by gentle plantar flexion and dorsiflexion of the foot. If the ankle joint cannot be easily identified, make a small vertical incision in the midline until synovial fluid exudes from the joint.
▪
Perform a transverse capsulotomy at the most medial aspect, stopping at the sheath of the posterior tibial tendon and the most lateral articulation of the tibiofibular joint. Do not divide the posterior tibial tendon sheath and its underlying deep deltoid ligament.
▪
If posterior subtalar capsulotomy is required, enter the subtalar joint at the most proximal aspect of the sheath of the flexor hallucis longus tendon, and extend the capsulotomy medially and laterally as necessary.
▪
Place the foot in 10 degrees of dorsiflexion and approximate the Achilles tendon to assess tension. Place the foot in plantarflexion and repair the Achilles tendon at the appropriate length.
▪
Deflate the tourniquet, obtain hemostasis with electrocautery, and close the wound in layers.
▪
Apply a long leg, bent-knee cast with the foot in 5 degrees of dorsiflexion.

Postoperative Care

The cast is removed 6 weeks after surgery. Postoperative bracing with an ankle-foot orthosis can be used for 6 to 9 months longer.

Several long-term evaluations of surgically treated clubfeet have demonstrated good results. The feet typically are plantigrade, functional, and relatively painless; however, persistent stiffness and mild discomfort with prolonged standing or activity are common. A number of recent studies have compared the long-term outcomes and functionality of clubfeet treated with the Ponseti method to those treated with extensive soft-tissue release. The Ponseti-treated feet had better range of motion, less pain, and less arthritis than the surgically treated feet. Every attempt should be made to avoid extensive surgical release.

Recalcitrant clubfeet

Treatment of residual or resistant clubfoot in an older child is one of the most difficult problems in pediatric orthopaedics. The deformity may take many forms, and there are no clear-cut guidelines for treatment. Each child must be evaluated carefully to determine which treatment would best correct his or her particular functional impairment. Thorough physical examination should include careful assessment of the forefoot and hindfoot. Residual forefoot deformity should be determined to be either dynamic (with a flexible forefoot) or rigid. The amount of inversion and eversion of the calcaneus and dorsiflexion and plantarflexion of the ankle should be determined. Any prior surgical procedures causing significant scarring around the foot or loss of motion should be noted. Standing anteroposterior and lateral radiographs should be obtained to assess anatomic measurements; if the clubfoot deformity is unilateral, the opposite foot can be used as a control for measurements. All possible causes of the persistent deformity, including underlying neuropathy, abnormal growth of the bones, or muscle imbalance, should be investigated. Most deformities have been reported to result from undercorrection at the time of the primary operation caused by failure to release the calcaneocuboid joint and plantar fascia and failure to recognize residual forefoot adduction on intraoperative radiographs; however, over-correction with hindfoot valgus or dorsal subluxation of the navicular is not uncommon.

Incomplete correction may not be obvious at the time of surgery, but it becomes apparent with growth as the persistent deformities become more evident ( Fig. 29.38 ). Clubfoot that appears by clinical and radiographic evaluation to be uncorrected may not always require surgery. The functional ability of the child, the severity of symptoms associated with the deformity, and the likelihood of progression if the deformity is left untreated must be considered when treatment decisions are being made. Repeat manipulation and casting should always be considered as an option for the recurrent clubfoot. Many difficult foot deformities can be improved or corrected with a series of repeat manipulations and castings.

FIGURE 29.38, Overcorrection of left clubfoot deformity apparent in 6-year-old girl.

Even if the repeat casting does not completely correct the residual or recurrent deformity, parts of the deformity often can be improved, lessening the degree of surgery required for full correction.

The basic surgical correction of resistant, recalcitrant clubfoot includes soft-tissue release and bony osteotomies. The appropriate procedures and combination of procedures depend on the age of the child, the severity of the deformity, and the pathologic processes involved. In general, the older the child, the more likely it is that combined procedures will be required. Children 2 to 3 years old may be candidates for the modified McKay procedure (see Technique 29.13), but if previous soft-tissue release has caused stiffness of the subtalar joint, osteonecrosis of the talus, or severe skin contractures, osteotomies are a better choice. Children older than 5 years almost always require osteotomies for correction of resistant deformity; children 3 to 5 years old constitute a gray area in which treatment guidelines are unclear and careful judgment is required. Common components of resistant clubfoot deformity are adduction or supination, or both, of the forefoot, a short medial column or long lateral column of the foot, internal rotation and varus of the calcaneus, and equinus.

Dorsal bunions that develop after clubfoot surgery have been attributed to muscle weakness, particularly of the triceps surae, wherein a bunion develops as the patient tries to push off with the toe flexors to compensate for the weakness of the triceps, or to imbalance between the anterior tibial muscle and an impaired peroneus longus muscle. Most authors recommend transfer of the flexor hallucis longus to the neck of the first metatarsal, combined with bony correction by plantar closing wedge osteotomy of the first metatarsal.

Correction of the forefoot with residual adduction or supination or both is similar to correction of isolated metatarsus adductus by multiple metatarsal osteotomies or by combined medial cuneiform and lateral cuboid osteotomies, when the deformity is in the forefoot. Because dynamic supination and adduction often are caused by overactivity of the anterior tibial tendon and underactivity of the peroneal tendon, a tendon-balancing procedure may be the most reasonable solution in the flexible foot.

Evaluation of the hindfoot should determine whether the deformity is caused by isolated heel varus, a long lateral column of the foot, or a short medial column. In children younger than 2 or 3 years who have had no previous surgery, residual heel varus may be corrected by extensive subtalar release, but children 3 to 10 years old who have residual soft-tissue and bony deformities usually require combined procedures.

Ankle valgus must be differentiated from hindfoot valgus because the methods and timing of surgical correction are different. For symptomatic ankle valgus, percutaneous medial malleolar epiphysiodesis using a 4.5-mm cortical screw has been recommended.

For isolated heel varus with mild supination of the forefoot, a Dwyer osteotomy with a lateral closing wedge osteotomy of the calcaneus can be performed. Opening wedge osteotomy of the calcaneus occasionally is followed by sloughing of tight skin along the incision over the calcaneus. Consequently, although some height of the calcaneus is lost after a lateral closing wedge osteotomy, most authors now prefer lateral closing wedge osteotomy with Kirschner wire fixation, if necessary. The ideal age for the operation is 3 to 4 years, but there is no upper age limit.

If the hindfoot deformity includes heel varus and residual internal rotation of the calcaneus with a long lateral column of the foot, the Lichtblau procedure may be appropriate. This procedure corrects the long lateral column of the foot by a closing wedge osteotomy of the lateral aspect of the calcaneus or by cuboid enucleation. The best results with this procedure are obtained in children 3 years old or older in whom the calcaneus and lateral column are long relative to the talus. Potential complications include the development of a “Z”-foot, or “skew”-foot, deformity.

Adductus of the forefoot, as measured by the calcaneal–second metatarsal angle has been reported to improve after combined cuboid-cuneiform osteotomy, with no further surgery required.

Residual heel equinus can be corrected by Achilles tendon lengthening and posterior ankle and subtalar capsulotomies in a younger child with a mild deformity. In rare cases, an isolated, fixed equinus deformity in an older child requires a Lambrinudi arthrodesis. Anterior distal tibial hemiepiphysiodesis as a method to correct ankle equinus has been shown to be ineffective in achieving the desired clinical result.

Talonavicular arthrodesis also has been described for residual midfoot deformities with or without lateral column shortening and a calcaneal wedge osteotomy with improvement in symptoms. This should be carefully considered if much of the foot motion is occurring at this joint.

If all three deformities are present in a child older than 10 years ( Fig. 29.39 ), triple arthrodesis may be appropriate. Internal tibial torsion occasionally occurs with resistant clubfoot deformity but rarely requires derotational osteotomy. Before tibial osteotomy is considered, it must be determined absolutely that the pathologic condition is confined to the tibia and is not a resistant deformity in the foot.

FIGURE 29.39, A and B, Deformities in 12-year-old boy after undercorrection of left clubfoot. Note metatarsus adductus, heel varus, and internal tibial torsion.

Correction using the Ilizarov device, with or without bony procedures, has been described for correction in children with severe soft-tissue and bony deformities.

The principles of Ilizarov correction of severe resistant clubfoot include stable bone fixation to the tibia as well as pin fixation to the talus, calcaneus, and forefoot. Some advocate partial soft-tissue release before gradual correction, but the risk of wound complications is greatly increased by this approach. After correction, soft-tissue release with or without arthrodesis also may be required to maintain correction and prevent recurrence. This approach offers the ability to maintain foot length while achieving a plantigrade position and three-dimensional deformity correction. However, the psychologic impact of Ilizarov treatment must be carefully considered, and rehabilitation can be quite challenging.

First Metatarsal Osteotomy and Tendon Transfer for Dorsal Bunion

Technique 29.15

Fig. 29.40 (SMITH AND KUO)

▪
Through a medial incision, expose the first metatarsal and perform a proximal plantar closing wedge osteotomy.
▪
Bring the metatarsal into alignment with the forefoot by plantarflexion and insert a Kirschner wire for fixation.
▪
Carry the incision distally or make a second incision at the metatarsophalangeal joint to allow identification and transection of the flexor hallucis longus tendon.
▪
Drill a hole in the distal first metatarsal neck in a dorsal-to-plantar direction.
▪
Pass the flexor hallucis tendon through the hole and suture it back on itself.
▪
Close the wounds and apply a short leg, non–weight-bearing cast.

FIGURE 29.40, A, Dorsal bunion in 9-year-old boy after clubfoot release at 9 months of age. B, Lateral view of dorsal bunion at metatarsophalangeal joint of left great toe. C, Postoperative appearance of left foot after plantar closing wedge osteotomy of first metatarsal with transfer of flexor hallucis longus to first metatarsal neck. SEE TECHNIQUE 29.15.

Postoperative Care

Non–weight bearing is continued in the cast for 6 weeks, after which the Kirschner wire is removed. A walking cast is worn for 4 weeks. Full activity usually can be resumed at 3 to 4 months.

Osteotomy of the Calcaneus for Persistent Varus Deformity of the Heel

Dwyer reported osteotomy of the calcaneus for relapsed clubfoot using an opening wedge osteotomy medially to increase the length and height of the calcaneus. The osteotomy is held open by a wedge of bone taken from the tibia. A modification of this technique is a laterally based closing wedge osteotomy of the calcaneus.

Technique 29.16

(DWYER, MODIFIED)

▪
Expose the calcaneus through a lateral incision over the calcaneus.
▪
Expose the lateral surface of the bone subperiosteally and with a wide osteotome resect a wedge of bone based laterally large enough, when removed, to permit correction of the heel varus. Do not injure the peroneal tendons.
▪
Remove the wedge of bone, place the heel into the corrected position, and close the incision with interrupted sutures.
▪
If necessary, fix the osteotomy with a Kirschner wire.
▪
Apply a short leg cast with the foot in the corrected position.

Postoperative Care

The Kirschner wire is removed at 6 weeks, and casting is discontinued at 8 to 12 weeks.

Medial Release with Osteotomy of the Distal Calcaneus

An alternative to calcaneocuboid arthrodesis is lateral closing wedge osteotomy of the calcaneus, as described by Lichtblau ( Fig. 29.41 ). This procedure may prevent the long-term stiffness of the hindfoot seen with the Dillwyn-Evans procedure.

Technique 29.17 Figure 29.42

(LICHTBLAU)

▪
If soft-tissue release medially is required, make an incision on the medial aspect of the foot beginning about 1 cm below the medial malleolus, crossing the tuberosity of the navicular, and sloping downward to the base of the first metatarsal. Identify and free the superior border of the abductor hallucis muscle and reflect it plantarward.
▪
Isolate the posterior tibial tendon at its insertion on the beak of the navicular, dissect it from its sheath, and perform a Z-plasty about 1 cm from its insertion. Allow the proximal end of the tendon to retract, using the distal end as a guide to the talonavicular joint.
▪
Resect the tendon sheath overlying the joint and open it generously on its medial, dorsal, and plantar aspects.
▪
Open the flexor tendon sheaths and lengthen them by Z-plasty technique.
▪
Make a lateral incision 4 cm long centered over the calcaneocuboid joint.
▪
Dissect the origin of the extensor digitorum brevis muscle from the calcaneus and reflect it distally to permit exposure and opening of the calcaneocuboid joint.
▪
Identify the distal end of the calcaneus and perform a wedge-shaped osteotomy, removing about 1 cm of the distal and lateral border of the calcaneus and 2 mm of the distal and medial border. Leave the articular surface of the calcaneus intact.
▪
Bring the cuboid into contact with the distal end of the calcaneus at the osteotomy site and evaluate the amount of correction of the varus deformity. If the cuboid cannot be closely approximated to the calcaneus, resect more of the calcaneus.
▪
A smooth Kirschner wire can be inserted across the calcaneocuboid joint to fix the osteotomy.
▪
Repair all soft tissues and close the subcutaneous tissue and skin. Apply a long leg cast with the foot in the corrected position.

Alternatively, the lateral-based, closing wedge can be removed from the cuboid instead of the calcaneus. This often is chosen for a patient with a deformity that seems to be most severe at the level of the midfoot rather than the hindfoot.

Postoperative Care

The long leg cast is changed to a short leg cast 3 weeks after surgery. The short leg cast is worn for 6 more weeks. The pin is removed at 8 to 12 weeks.

FIGURE 29.41, A-D, Severe residual clubfoot deformity in 5-year-old child on anteroposterior ( A ) and lateral ( C ) radiographs. B and D, After Lichtblau procedure. SEE TECHNIQUE 29.17.

Selective Joint-Sparing Osteotomies for Residual Cavovarus Deformity

Described by Mubarak and Van Valin, selective joint-sparing osteotomies of the foot can be used for multiple etiologies that result in rigid cavus and cavovarus foot deformities, including hereditary motor sensory neuropathies, traumatic brain injury, spinal cord lipoma, and residual or recurrent clubfoot. The technique involves stepwise correction of each aspect of the deformity with a closing wedge osteotomy of the first metatarsal, opening plantar wedge osteotomy of the medial cuneiform, closing wedge osteotomy of the cuboid, osteotomies of the second and third metatarsals, sliding osteotomy of the calcaneus, plantar fasciotomy, and peroneus-to-brevis transfer. Indications for this procedure are rigid cavus or cavovarus deformity, ankle or foot instability symptoms including pain, painful metatarsal heads and callosities, and ankle or foot sprains or fractures.

Technique 29.18

(MUBRAK AND VAN VALIN)

▪
To correct rigid cavus, make an incision along the medial foot over the first metatarsal and medial cuneiform.
▪
Partially free the anterior tibial tendon to expose the cuneiform.
▪
Under fluoroscopic guidance, place intraosseous needles or small Kirschner wires in the mid-portion of the medial cuneiform and 1 cm distal to the first metatarsal physis. Take care not to disturb the physis.
▪
Perform a dorsal, closing-wedge osteotomy of the first metatarsal by removing a large 20- to 30-degree wedge ( Fig. 29.43A ). Then create a plantar-based, opening wedge osteotomy of the medial cuneiform and insert the bone wedge ( Fig. 29.43B ). Stabilize both osteotomies with Kirschner wires.
▪
To correct forefoot varus, make a longitudinal lateral incision overlying the cuboid. Identify the calcaneocuboid and cuboid-fifth metatarsal joints with fluoroscopy and protect these joints. Create a laterally based, closing-wedge osteotomy of the cuboid by removing a triangular wedge of bone with a base size of 5 to 10 mm ( Fig. 29.43C ). Stabilize the osteotomy with a Kirschner wire.
▪
If second and third metatarsal head prominence remains after the osteotomies have been completed, dorsal closing wedge osteotomies of the second and third metatarsals are required. Make a single incision overlying the bases of the second and third metatarsals. Create dorsally a slightly lateral based closing wedge osteotomy of the base of each metatarsal and stabilize them with intramedullary Kirschner wires.
▪
For rigid hindfoot varus, perform a Dwyer osteotomy of the calcaneus (see Technique 29.16).
▪
Next, evaluate the plantar fascia. If this structure is tight, perform a plantar fasciotomy (Technique 83.6 in Tenth Edition).
▪
For deformities caused by neurologic conditions, consider a peroneus longus-to-brevis transfer. Through the same incision used for the cuboid osteotomy, release the peroneus longus just under the cuboid and reattach it to the brevis.
▪
Close the incision. Apply a bivalved, short leg cast.

Postoperative Care

The bivalved cast is closed at 1 week. Non–weight bearing is continued for 4 weeks. Then the pins are removed under sedation anesthesia and a short leg cast is applied. Weight bearing is allowed in the second cast for 4 more weeks.

Triple Arthrodesis and Talectomy for Uncorrected Clubfoot

Triple arthrodesis and talectomy generally are salvage operations for uncorrected clubfoot in older children and adolescents ( Figs. 29.44 and 29.45 ). Triple arthrodesis corrects the severely deformed foot by a lateral closing wedge osteotomy through the subtalar and midtarsal joints. Functional results generally are improved despite postoperative joint stiffness. Talectomy should be reserved for severe, untreated clubfoot; for previously treated clubfoot that is uncorrectable by any other surgical procedures; and for severe, recalcitrant, neuromuscular clubfoot.

FIGURE 29.44, A, Untreated clubfoot in 14-year-old girl. B, Recurrent left hindfoot varus in 8-year-old girl.

FIGURE 29.45, A, Overcorrected clubfoot in 12-year-old boy showing hindfoot valgus, dorsal dislocation of navicular on talus, and dorsal bunion deformity. B, Standing lateral radiograph.

Triple Arthrodesis

Technique 29.19

▪
Make an incision along the medial side of the foot parallel to the inferior border of the calcaneus.
▪
Free the attachments of the plantar fascia and of the short flexors of the toes from the plantar aspect of the calcaneus.
▪
By manipulation, correct the cavus deformity as much as possible.
▪
Through an oblique anterolateral approach, expose the midtarsal and subtalar joints ( Fig. 29.46 ).
▪
Resect a laterally based wedge of bone that includes the midtarsal joints. Resect enough bone to correct the varus and adduction deformities of the forefoot.
▪
Through the same incision, resect a wedge of bone, again laterally based, which includes the subtalar joint. Resect enough bone to correct the varus deformity of the calcaneus. If necessary, include in the wedge the navicular and most of the cuboid and lateral cuneiform and the anterior part of the talus and calcaneus, and in the second wedge include much of the superior part of the calcaneus and the inferior part of the talus.
▪
Lengthen the Achilles tendon by Z-plasty and perform a posterior capsulotomy of the ankle joint. By manipulating the ankle, correct the equinus deformity.
▪
Hold the correct position with a Kirschner wire inserted through the calcaneocuboid and talonavicular joints or with staple fixation.

Postoperative Care

With the foot in the corrected position and the knee flexed 30 degrees, a long leg cast is applied from the base of the toes to the groin. The Kirschner wire and cast are removed at 6 weeks. A short leg walking cast is worn for 4 more weeks.

Talectomy

Trumble et al. described a talectomy for clubfoot deformity in patients with myelomeningocele, but the technique can be modified for treatment of a severe, resistant, idiopathic clubfoot deformity. Outcomes are acceptable with these very severe deformities provided the talus is completely removed and the calcaneus is properly positioned.

Technique 29.20

(TRUMBLE ET AL.)

▪
Expose the talus through an incision parallel to the inferior border of the calcaneus ( Fig. 29.47A ). If additional soft-tissue release is required, talectomy can be done after circumferential release (see Technique 29.12).
▪
Carry the dissection to the prominent lateral articular margin of the navicular in the interval between the extensor digitorum longus and peroneus tertius tendons. Invert and plantar flex the forefoot.
▪
Place a towel clip around the neck of the talus and deliver it into the wound; dissect all of its ligaments ( Fig. 29.47B ). Excise the talus intact because retained remnants of cartilage may interfere with proper positioning of the foot; these remnants also may grow and cause later deformity and loss of correction.
▪
Derotate the forefoot and displace the calcaneus posteriorly into the ankle mortise until the navicular abuts the anterior edge of the tibial plafond. The exposed articular surface of the tibial plafond should be opposite the middle articular facet of the calcaneus. If necessary to obtain adequate posterior displacement, excise the tarsal navicular.
▪
Section the deltoid and the lateral collateral ligaments of the ankle.
▪
Correct equinus deformity of the hindfoot by sectioning the Achilles tendon and allowing its proximal end to retract.
▪
In feet with uncorrected, severe equinovarus deformity, the dome of the talus may be extruded anterior to its normal relationship in the ankle mortise. Adaptive narrowing of the mortise may require release of the anterior and posterior tibiofibular ligaments of the syndesmosis to allow proper posterior positioning of the calcaneus.
▪
In the proper plantigrade position, the long axis of the foot should be aligned at a right angle to the bimalleolar axis of the ankle, not to the axis of the knee joint. This usually requires 20 to 30 degrees of external rotation of the foot.
▪
When the proper position has been achieved, insert one or two Steinmann pins from the heel through the calcaneus and into the distal tibia.
▪
Apply a long leg cast with the knee flexed to 60 degrees.

Postoperative Care

The Steinmann pins are removed at 6 weeks and a below-knee, weight-bearing cast is applied. The cast is worn for 12 more weeks.

Calcaneovalgus foot

Calcaneovalgus foot deformity is a benign soft-tissue contracture that is present in its mildest form in up to 40% of newborns. The condition is characterized by hindfoot eversion and dorsiflexion without true dislocation of any of the joints of the hindfoot or midfoot. The etiology is consistent with a classic intrauterine “packaging” problem, and it is therefore more common in first-born children.

On physical examination, the foot has a severe flat appearance with hindfoot eversion, and in some cases the dorsum of the foot can rest on the anterior surface of the tibia. In most cases, however, the foot is passively correctable at the time of birth or soon after. In contrast to the more severe and rigid congenital vertical talus, calcaneovalgus foot deformity has no hindfoot equinus ( Fig. 29.48 ).

Imaging rarely is indicated for this condition in the newborn period; however, if there is any question as to the exact diagnosis, a forced dorsiflexion and forced plantarflexion lateral radiograph of the foot can distinguish calcaneovalgus deformity from congenital vertical talus. In calcaneovalgus foot, the forced plantarflexion lateral radiograph will reveal alignment of the first metatarsal with the long axis of the talus; on the forced dorsiflexion image, the hindfoot will dorsiflexion out of equinus.

Treatment involves observation and periodic passive stretching exercises. The foot can be plantarflexed, adducted, and inverted multiple times a day during diaper changes and baths. The condition typically resolves completely by the third to sixth month of life. Casting rarely is indicated. Should casting be required, the deformity is likely a form of the more severe condition, congenital vertical talus.

Congenital vertical talus

Congenital vertical talus, rocker-bottom flatfoot, or congenital rigid flatfoot must be distinguished from flexible pes planus commonly seen in infants and children. Congenital vertical talus may be associated with numerous neuromuscular disorders, such as arthrogryposis and myelomeningocele, but it also may occur as an isolated congenital anomaly.

Clinical and radiographic findings

Congenital vertical talus usually can be detected at birth by the presence of a rounded prominence of the medial and plantar surfaces of the foot produced by the abnormal location of the head of the talus ( Fig. 29.49 ). The talus is so distorted plantarward and medially as to be almost vertical. The calcaneus also is in an equinus position, but to a lesser degree. The forefoot is dorsiflexed at the midtarsal joints, and the navicular lies on the dorsal aspect of the head of the talus. The sole is convex, and there are deep creases on the dorsolateral aspect of the foot anterior and inferior to the lateral malleolus.

FIGURE 29.49, A, Bilateral congenital vertical talus in 14-month-old child. B, At 6 years of age, after bilateral operative correction at age 14 months in which transverse circumferential approach was used.

As the foot develops and weight bearing begins, adaptive changes occur in the tarsals. The talus becomes shaped like an hourglass but remains in so marked an equinus position that its longitudinal axis is almost the same as that of the tibia, and only the posterior third of its superior articular surface articulates with the tibia. The calcaneus remains in an equinus position also and becomes displaced posteriorly, and the anterior part of its plantar surface becomes rounded. Callosities develop beneath the anterior end of the calcaneus and along the medial border of the foot superficial to the head of the talus. When full weight is borne, the forefoot becomes severely abducted, and the heel does not touch the floor. Adaptive changes occur in the soft structures. All the capsules, ligaments, and tendons on the dorsum of the foot become contracted. The posterior tibial and peroneus longus and brevis tendons may come to lie anterior to the malleoli and act as dorsiflexors rather than plantar flexors.

Congenital vertical talus can be difficult to distinguish from severe pes planus, although the two can be differentiated by the use of appropriate radiographs or ultrasound. The plantarflexion lateral radiograph is most helpful to confirm the diagnosis of congenital vertical talus ( Fig. 29.50 ). In the case of pes planus or calcaneovalgus foot deformity, a forced plantarflexion lateral radiograph will demonstrate alignment of the talus and the first metatarsal. In congenital vertical talus, the alignment is not restored by simply plantarflexing the forefoot.

FIGURE 29.50, Plantarflexion lateral stress radiographs in diagnosis of congenital vertical talus. A, In normal foot, long axis of first metatarsal passes plantarward to long axis of talus. B, Forced plantarflexion lateral demonstrates inability of first metatarsal to line up with the talus. C, After 5 weeks of casting the plantarflexion lateral demonstrates good alignment of the first metatarsal and talus. D, After percutaneous pinning of talonavicular joint and percutaneous Achilles tenotomy.

Treatment

Congenital vertical talus is difficult to correct and tends to recur. Dobbs described the use of outpatient serial casting to achieve relaxation of the dorsolateral structures of the foot and partial or complete reduction of the talonavicular joint followed by percutaneous retrograde pinning or open reduction and retrograde pinning of the talonavicular joint in the operating room. Once the talonavicular joint is stabilized by pin fixation, percutaneous Achilles tenotomy is done to achieve ankle dorsiflexion without persistent rocker-bottom deformity. Excellent results in terms of clinical appearance, function, and deformity correction have been reported by a number of authors, and this technique has emerged as a viable initial option for many patients with congenital vertical talus (see ) .

Persistent or recurrent deformity after a trial of casting may necessitate more extensive operative intervention, particularly in children with more severe or rigid deformities.

The exact surgery indicated is determined by the age of the child and the severity of the deformity. Children 1 to 4 years old generally are best treated by open reduction and realignment of the talonavicular and subtalar joints. Occasionally, in children 3 years old or older who have a severe deformity, navicular excision is required at the time of open reduction. Children 4 to 8 years old can be treated by open reduction and soft-tissue procedures combined with extraarticular subtalar arthrodesis. Children 12 years old or older are best treated by triple arthrodesis for permanent correction of the deformity.

Kodros and Dias reported a single-stage procedure in which a threaded Kirschner wire is used as a “joystick” to manipulate the talus into correct position. The corrected position is held with threaded Kirschner wires across the talonavicular and subtalar joints ( Fig. 29.51 ).

FIGURE 29.51, Single-stage correction of congenital vertical talus. A, After soft-tissue release, a threaded Kirschner wire is placed axially in the vertical talus from posterior and is used as “joystick” to manipulate talus into reduced position. B, Wire is advanced across talonavicular joint.

For a young child with a mild or moderate deformity, the technique of Kumar, Cowell, and Ramsey is recommended.

Open Reduction and Realignment of Talonavicular and Subtalar Joints

Technique 29.21

(KUMAR, COWELL, AND RAMSEY)

▪
Make the first of three incisions on the lateral side of the foot, centered over the sinus tarsi, or use the transverse circumferential (Cincinnati) approach ( Fig. 29.34 ), which we prefer.
▪
Expose the extensor digitorum brevis and reflect it distally to expose the anterior part of the talocalcaneal joint.
▪
Identify the calcaneocuboid joint and release all tight structures around it, including the calcaneocuboid ligament.
▪
Make the second incision on the medial side of the foot, centered over the prominent head of the talus. This exposes the head of the talus and medial part of the navicular.
▪
The anterior tibial tendon also is exposed; if the tendon is contracted, lengthen it by Z-plasty. Alternatively, release the anterior tibial tendon from its attachment to the medial cuneiform and first ray and transpose it into the planter aspect of the repaired talonavicular capsule, which is our preferred technique.
▪
Release all tight structures on the medial and dorsal aspects of the head of the talus and the navicular. Free also the anterior part of the talus from its ligamentous attachments to the navicular and calcaneus. This includes releasing the dorsal talonavicular ligament, the plantar calcaneonavicular ligament, and the anterior part of the superficial deltoid ligament. If necessary, divide part of the talocalcaneal interosseous ligament so that the talus can be easily maneuvered into position by a blunt instrument. If the peroneal, extensor hallucis longus, and extensor digitorum longus tendons remain contracted, expose and lengthen them by Z-plasty. Alternatively, perform a fractional lengthening of these tendons through an anterior incision at the musculotendinous junction.
▪
Make a third incision 2 inches long on the medial side of the Achilles tendon. Lengthen this tendon by Z-plasty, and, if necessary, perform a capsulotomy of the posterior ankle and subtalar joints.
▪
The talus and calcaneus can now be placed in the corrected position, and the forefoot can be reduced on the hindfoot.
▪
Pass a Kirschner wire through the navicular and into the neck of the talus to maintain the reduction. Obtain anteroposterior and lateral radiographs to confirm reduction of the vertical talus ( Fig. 29.52 ). This pin can be advanced into the dorsum of the foot and cut flush with the back of the talus and can be removed weeks later through a small dorsal incision.
▪
Reconstruct the talonavicular ligament, repair any lengthened tendons, transfer the anterior tibial tendon to the plantar aspect of the talonavicular joint capsule, and close the wound in layers.
▪
Apply a long leg cast with the knee flexed and the foot in proper position.

Postoperative Care

At 8 weeks, the cast and Kirschner wire are removed. A new long leg cast is applied, and this type of cast is worn for 1 month. A short leg cast is worn for an additional month. The foot is supported in an ankle-foot orthosis for another 3 to 6 months.

Open Reduction and Extraarticular Subtalar Fusion

Coleman et al. described open reduction and extraarticular subtalar fusion in older children with severe or recurrent deformities. This technique combines the procedure of Kumar et al. with a Grice-Green fusion performed 6 to 8 weeks later. Dennyson and Fulford modified this technique by using screw fixation across the talocalcaneal joint.

Technique 29.22

(GRICE-GREEN)

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Make a short curvilinear incision on the lateral aspect of the foot directly over the subtalar joint.
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Carry the incision down through the soft tissues to expose the cruciate ligament overlying the joint. Split this ligament in the direction of its fibers and dissect the fatty and ligamentous tissues from the sinus tarsi.
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Dissect the short toe extensors from the calcaneus and reflect them distally. The relationship of the calcaneus to the talus now can be determined, and the mechanism of the deformity can be shown.
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Place the foot in equinus and invert it to position the calcaneus beneath the talus.
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A severe, long-standing deformity may require division of the posterior capsule of the subtalar joint or removal of a small piece of bone laterally from beneath the anterosuperior articular surface of the calcaneus.
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Insert an osteotome or broad periosteal elevator into the sinus tarsi and block the subtalar joint to evaluate the stability of the graft and its proper size and position.
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Prepare the graft beds by removing a thin layer of cortical bone from the inferior surface of the talus and superior surface of the calcaneus ( Fig. 29.53 ).
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Make a linear incision over the anteromedial surface of the proximal tibial metaphysis, incise the periosteum, and take a block of bone large enough for two grafts (usually 3.5 to 4.5 cm long and 1.5 cm wide). As an alternative to tibial bone, a short segment of the distal fibula or a circular segment of the iliac crest can be used.
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Cut the grafts to fit the prepared beds. Use a rongeur to shape the grafts so that they can be countersunk into cancellous bone to prevent lateral displacement.
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With the foot held in a slightly overcorrected position, place the grafts in the sinus tarsi. Evert the foot to lock the grafts in place.
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If a segment of the fibula or iliac crest is used, a smooth Kirschner wire can be used to hold the graft in place for 12 weeks, or a screw can be inserted anteriorly from the talar neck into the calcaneus for rigid fixation ( Fig. 29.54 ).
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The foot should be stable enough to allow correction of equinus deformity by Achilles tendon lengthening if necessary.
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Apply a long leg cast with the knee flexed, the ankle in maximal dorsiflexion, and the foot in the corrected position.

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