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This chapter will focus on managing complications and unplanned outcomes following hallux valgus corrective surgical procedures. The chapter is divided into three sections: (1) Soft tissue complications, (2) hallux varus, and (3) managing failed bunion procedures. Unplanned results can occur, even among the best of surgeons, surgical technique, and patient compliance. A thorough and transparent informed discussion and consent process is critical to create expectations on the part of patients and their caregivers. While most bunion surgeries result in an uneventful recovery process, when complications occur, it can be stressful and resource consuming for patients. Thus, ensuring that patients are aware of what to expect during the normal postoperative course, and what to look for to identify complications early, is critical. Following patients carefully and identifying unplanned results and managing both the complication and patient expectations are important to optimizing outcomes following bunion surgery.
A postoperative infection may be superficial or deep. The clinician must be constantly aware of the possibility of postoperative infection and treat it vigorously if it develops. It is very important to determine as quickly as possible whether an infection is superficial to the MTP joint or whether it involves the joint itself ( Fig. 8-1 ).
Generally speaking, a superficial infection is manifested by local cellulitis and, on occasion, evidence of ascending lymphangitis. The skin over the involved area may be red and warm, but motion of the joint will not usually cause significant pain. Attempts at aspiration of the MTP joint through an area of cellulitis are discouraged because of the risk of spreading a superficial infection into the joint space. Clinically, fever will usually develop in a patient with a superficial infection. Hematologic data may indicate an increase in the white blood cell (WBC), sedimentation rate, and C-reactive protein. Clinical judgment is important in choosing treatment, and the use of either oral or systemic antibiotics is indicated ( Fig. 8-2 ).
A deep infection involving the MTP joint and/or deeper tissues is much more severe and concerning and is usually manifested as a marked increase in pain and swelling about the MTP joint. There may be evidence of purulent discharge from the wound. MTP joint motion will typically cause discomfort, as will palpation of the joint itself. Often a fever is present, and the WBC count, C-reactive protein, and sedimentation rate are generally elevated. Management should be directed toward obtaining a specific culture and sensitivity of the offending organism and irrigating and debriding the joint and wound to remove purulent and destructive fluid and material. Prompt treatment with parenteral antibiotics is indicated. With purulent drainage, a decision must be made expeditiously regarding whether prompt irrigation and debridement of the joint are indicated.
With a severe joint space infection, marked intraarticular joint fibrosis and degenerative arthritis may ensue due to destruction of the articular cartilage. Changes in periarticular soft tissues after the infection may lead to recurrence of the original deformity. Consultation of an infectious disease expert can be helpful to determine the proper antibiotic agent and course of treatment.
On occasion after any forefoot surgery, the operative wound edges appear to be locally reddened and slightly separated. There is no evidence of surrounding cellulitis or purulent drainage. The joint itself is not usually particularly swollen, and motion of the joint does not cause increased discomfort. Such cases are often caused by a superficial fungal infection. Carbolfuchsin (Carfusin) painted on the wound on one or two occasions will generally result in prompt wound healing with no further sequelae. Wound care should be initiated including antimicrobial agents and dressing changes. In the presence of increasing evidence of cellulitis, a more serious problem should be suspected and treated accordingly.
On occasion after surgery, a partial- or full-thickness slough about the wound may occur. Sloughing usually develops 7 to 14 days after surgery and, depending on its size, may create a significant problem. The cause of the sloughing is devascularization of the involved tissue ( Fig. 8-3 ), which can result from insufficient circulation secondary to a dysvascular foot, excessive retraction on the skin edge at surgery, placement of the skin under tension after correction of a severe deformity or increased swelling, or pressure from the postoperative dressing ( Fig. 8-4 ).
Treatment varies depending on the severity of the tissue loss. In the case of a minor partial-thickness skin slough, local treatment and the passage of time usually result in a satisfactory outcome. Sloughing caused by a dysvascular foot may require revascularization of the extremity before satisfactory wound healing can occur. Other larger, full-thickness skin sloughs may eventually require skin grafting after a satisfactory granulating bed has been achieved or could even require amputation.
Even after a successful surgical correction, a scar of skin and subcutaneous tissue can occasionally form that is adherent to the underlying tissue layer. If a full-thickness dissection includes the underlying fatty tissue when skin flaps are developed at the time of the initial surgery, an adherent scar seldom occurs. As a general rule, an adherent scar may actually soften over time, thus rendering it less bothersome to the patient. Soft tissue and underlying fatty tissue are generally somewhat limited on the foot, and excision of a persistent, adherent scar will not usually result in significant improvement of the situation. Persistent massage of an adherent scar may in time help mobilize the restricted tissue. Silicone gel–based sheets and gels can improve scar outcomes.
Entrapment or severance (partial or complete) of a cutaneous nerve may result in either dysesthesia or anesthesia distal to the involved nerve. Protection of sensory nerves at the time of surgery is paramount; however, once a nerve injury occurs, desensitization of the involved area is managed by frequent massaging, rubbing, or tapping. This will often produce a satisfactory result over a period of several months. On occasion, it is necessary to explore and decompress the injured nerve and further resect the nerve proximally to an area of soft tissue to diminish the symptoms. Wrapping of nerves with various techniques can be helpful to improve subjective outcomes. The use of a transcutaneous nerve stimulator may be effective if surgical intervention fails. On rare occasions, a regional pain syndrome may develop (see Chapter 20 ).
Due to its proximity to the deformity and surgical approach, the nerve most frequently involved is the dorsomedial cutaneous nerve to the great toe ( Fig. 8-5A ). An incision on the dorsomedial aspect of the first MTP joint unfortunately overlies this cutaneous nerve. On occasion, this nerve can be stretched or severed at the time of surgery or later become entrapped in scar tissue ( Fig. 8-6 ). As a general rule, neurolysis is rarely helpful if the nerve has been partially severed or severely injured. Exploration of the injured nerve through a long, dorsomedial incision enables the identification of normal and injured nerve. After carefully freeing the nerve from surrounding scar tissue and sectioning the nerve more proximally, the nerve is then transferred beneath and sutured under minimal tension to the abductor hallucis muscle. In this way, the nerve is transferred from an area of painful scar tissue to an area where there is little or no pressure. Although an area of numbness over the dorsomedial aspect of the great toe remains, the dysesthetic area is no longer present. The numbness is much less bothersome to patients in general compared to dysesthesias.
The plantar medial cutaneous nerve just plantar to the abductor hallucis tendon can also be injured. Symptoms develop with ambulation as the MTP joint dorsiflexes with plantar pressure over the neuroma, and often a patient transfers weight to the lateral border of the foot. Again, surgical treatment consists of exposing the plantar medial cutaneous nerve through a long medial incision just dorsal to the weight-bearing surface. The nerve is identified and traced proximally to normal nerve tissue. After the nerve has been freed and sectioned, it is buried proximally beneath the abductor hallucis muscle. At the time of transposition, the sectioned nerve is sutured with a minimum of tension so that as the toes are brought into dorsiflexion, symptoms will not be exacerbated. After sectioning of the injured nerve, there is residual numbness along the plantar medial aspect of the great toe.
On occasion, the common digital nerve to the first web space is partially or completely transected with exploration of the first web space. If a neuroma develops, there may be sensitivity on the plantar aspect of the foot, as well as dysesthesias on the plantar aspect of the first web space (see Fig. 8-5B ). Surgical treatment involves exposure through a dorsal first web-space incision. The transverse metatarsal ligament is sectioned and the common digital nerve identified and carefully freed from surrounding tissue. If a significant neuroma is identified and transection of the nerve is necessary, it should be performed with as much length of the nerve left as possible. This ensures that the remaining stump can be elevated to an area alongside the first metatarsal so that the nerve end (where another neuroma will form) is removed from the plantar aspect of the foot. Proximal transection of the common digital nerve without elevation of the stump frequently results in a painful neuroma located more proximally in the foot. At times the common digital nerve can be freed from the adjacent soft tissue; if the nerve appears to be abnormal, it can be elevated off the plantar aspect of the foot and transferred above a portion of the adductor hallucis muscle so that the nerve is not exposed to the trauma of weight bearing.
On occasion after successful surgery and wound healing, the wound will once again become swollen and sensitive. This usually occurs 4 weeks or more postoperatively but may occur many months after surgery. Frequently, the cause is a foreign body reaction to the underlying suture material. It frequently involves silk, but other suture materials (e.g., cotton, chromic, newer synthetic materials) may be involved. The area of the reaction forms a sterile abscess, the skin breaks down, and a suture granuloma develops. With time, the involved foreign material is usually extruded. On occasion, exploration of the wound may be necessary to excise the foreign material. Once removed, prompt wound healing generally occurs, although cauterization of the remaining granulation material with silver nitrate is often required.
Hallux varus refers to a medial deviation of the great toe. Similar to hallux valgus deformities, hallux varus has varying degrees of severity, etiologies, and symptom severity. This condition can occur on a congenital basis, although, unlike hallux valgus, the large majority of hallux varus cases are not congenital ( Fig. 8-7 ). Most often, hallux varus is a deformity acquired after a traumatic injury to the lateral collateral ligament of the hallux MTP joint complex, or following surgical correction of a bunion deformity. Hallux varus most often occurs after a distal soft tissue or McBride type of bunionectomy, but it can also be observed after the chevron, Mitchell, Keller, and Lapidus procedures ( Fig. 8-8 ).
The classic hallux varus deformity after the McBride procedure, in which excision of the fibular sesamoid is followed by MTP joint hyperextension, IP joint flexion, and medial deviation of the hallux. Anatomically, this deformity results from a muscle imbalance caused by medial dislocation of the tibial sesamoid, although other factors are involved as well ( Fig. 8-9A ).
The MTP joint is flexed by the flexor hallucis brevis muscle primarily through its pull on the sesamoid complex. After fibular sesamoid excision, the MTP joint hyperextends as the metatarsal head “buttonholes” through the soft tissue defect created by the deficiency in the flexor hallucis brevis. The medial deviation is aggravated by the detachment of the adductor tendon when the medial sesamoid is removed and compounded by the unopposed pull of the abductor hallucis muscle.
With time, it becomes a fixed deformity that makes it difficult for the patient to obtain comfortable footwear. The IP joint of the great toe becomes flexed because the long extensor tendon can no longer effectively extend the IP joint. Simultaneously, the long flexor tendon is stretched around the metatarsal head, which creates a constant flexion force on the IP joint. In time, this entire deformity becomes rigid. When the metatarsal head does not buttonhole through the soft tissue defect, the hallux varus deformity consists mainly of medial deviation of the proximal phalanx without any significant cock-up deformity of the MTP joint or flexion of the IP joint (see Fig. 8-9B-D ). The following soft tissue factors can contribute to the development of a hallux varus deformity following bunion surgery:
Overplication of the medial capsule ( Fig. 8-10A )
Medial displacement of the tibial sesamoid (see Fig. 8-10B and C )
Removal of the fibular sesamoid with inadequate repair of plantar tissues (see Fig. 8-10D )
Overpull of the abductor hallucis muscle against an incompetent lateral ligamentous complex ( Fig. 8-11A-E )
Overcorrection with a postoperative dressing holding the MTP joint in a varus position
Excessive resection of the medial eminence (see Fig. 8-11F and G )
Hallux varus may occur after a proximal or distal metatarsal osteotomy when the metatarsal head is translated too far laterally, or if too much metatarsal head is resected, the potential exists for MTP joint instability and hallux varus.
With a chevron osteotomy, if the capital fragment is excessively displaced laterally, a hallux varus deformity can develop ( Fig. 8-12A ). Likewise, with a proximal osteotomy, the distal segment can be translated too far laterally (see Fig. 8-12B-G ). With a crescentic osteotomy, the concavity can be directed distally toward the great toe. If the metatarsal osteotomy site is translated too far medially, excessive lateral translation of the metatarsal head occurs. Once this problem was recognized, the concavity was reversed so that it faced proximally toward the heel. With this orientation, overtranslation rarely occurs because the distal metatarsal segment is locked into the proximal segment. Less commonly, a lateral closing-wedge or proximal chevron osteotomy or Lapidus procedure can be overcorrected. This can create the dual deformity of overcorrection and shortening.
Hallux varus deformities visible clinically or on radiographs do not always create symptoms. It is important to discuss with patients whether the position of the toe creates symptoms for the patient versus is solely a cosmetic concern. A hallux varus deformity must be carefully evaluated to determine which salvage procedure is appropriate. If the varus deformity is caused by overplication of the medial capsule, release of the medial capsule may be sufficient. With a fixed deformity, however, a soft tissue capsular release is rarely effective. Plication of the lateral capsule can be added to the medial capsular release, but this does not generally produce a lasting result. On occasion, the surgeon may encounter a mild varus deformity, and yet the sesamoids remain well aligned. In this instance, the surgeon may perform a phalangeal osteotomy to realign the hallux. This “reverse Akin” osteotomy may be performed through the prior medially based incision ( Fig. 8-13 ). These more mild and passively correctable varus deformities may also be amenable to a realignment procedure by using suture-button fixation. This minimally invasive technique allows rebalancing of the joint via medial soft tissue release and lateral fixation ( Fig. 8-14 ). A tendon allograft may also be used to augment the repair.
With medial displacement of the tibial sesamoid after excision of the fibular sesamoid or excessive resection of the medial eminence, a more aggressive surgical repair may be necessary. In the initial determination, the question is whether sufficient articular surface remains to permit adequate joint function after realignment. In the presence of degenerative arthrosis, a soft tissue reconstruction is contraindicated because the MTP joint will only deteriorate further. Arthrodesis is the appropriate salvage procedure, although MTP joint motion is sacrificed.
In a hallux varus deformity with reasonable articular surface remaining, the extensor hallucis longus tendon can be used to create a dynamic correction of the deforming forces. Initially, the entire extensor hallucis longus tendon was transferred beneath the transverse metatarsal ligament and inserted into the base of the proximal phalanx of the great toe. This was coupled with IP joint arthrodesis. Although this technique can produce a satisfactory result, if the IP joint does not have a fixed deformity (or can be straightened to within 10–15 degrees of full extension), it is not necessary to sacrifice IP joint function. Furthermore, if the extensor hallucis longus transfer fails and MTP joint arthrodesis is necessary, a mobile and functional IP joint is preferable. Therefore the authors modified the original procedure and split the extensor hallucis longus tendon. A portion is transferred and a portion is left intact to control the IP joint of the hallux.
The surgical technique for correction of hallux varus is divided into the surgical approach and preparation for the tendon transfer, release of the medial joint contracture, and reconstruction of the MTP joint.
A dorsal curvilinear incision is made starting just lateral to the insertion of the extensor hallucis longus tendon. The incision is carried laterally toward the first web space and follows the interval between the first and second metatarsals. It is then inclined medially and ends along the lateral aspect of the extensor hallucis longus tendon in the region of the first MTC joint ( Fig. 8-15A ).
The extensor hallucis tendon is dissected free of soft tissue attachments, and the lateral two thirds of the tendon is released from its insertion. Starting with the free end, the tendon is carefully “teased out” proximally to the level of the MTC joint (see Fig. 8-15B ). If when developing the lateral two thirds of the tendon the remaining portion of the tendon is inadvertently ruptured, it can be repaired by suturing the extensor hallucis brevis tendon to it.
The transverse metatarsal ligament is identified and a right-angle clamp or Mixner clamp is passed beneath it. Even if the transverse metatarsal ligament had been released at the time of the initial surgery, a sufficient amount of ligament usually re-forms. This remnant of the transverse metatarsal ligament is used as a pulley for the extensor tendon (see Fig. 8-15C ). A ligature is passed beneath the transverse metatarsal ligament to be used later in the procedure for pulling the extensor hallucis longus tendon beneath it.
The medial aspect of the MTP joint is approached through a long midline incision, beginning just proximal to the IP joint and ending at the midportion of the metatarsal shaft. Full-thickness dorsal and plantar skin flaps are developed, with care taken to avoid the cutaneous nerves. Too thin a skin flap can inadvertently result in sloughing of skin.
The medial joint capsule is cut obliquely starting at the plantar medial aspect of the base of the proximal phalanx where the abductor hallucis tendon inserts. The capsulotomy proceeds obliquely in a proximal and dorsal direction. This flap is dissected off the metatarsal head to permit the proximal phalanx to be brought out of its fixed varus deformity. A 5- to 7-mm gap is usually created in the capsular tissue.
The abductor hallucis tendon is identified beneath the cut in the capsule, and a long oblique cut releases the last remaining deforming force. At this point, the proximal phalanx can be brought into a valgus position with no resistance. If resistance is still present, some residual medial structure has not been adequately released.
If the tibial sesamoid is displaced medially, the abductor hallucis tendon must be freed from its attachment to it to permit the sesamoid to be placed back beneath the metatarsal head. If too much of the metatarsal head was resected at the initial surgery and the sesamoid cannot be replaced beneath the metatarsal head or if the medial sesamoid is too prominent, excision of the sesamoid should be considered (see Fig. 8-15D ).
If an MTP joint dorsiflexion contracture is present, it is treated by releasing the dorsal capsule, which enables the MTP joint to be brought into approximately 10 degrees of plantar flexion.
A transverse drill hole in the base of the proximal phalanx is started in the midline. It is important that the hole be drilled distal enough so that it does not inadvertently penetrate the articular surface of the proximal phalanx (see Fig. 8-15E ).
A ligature is placed on the end of the extensor hallucis longus tendon and is used to pass the tendon beneath the transverse metatarsal ligament.
With the ankle joint in dorsiflexion (which relaxes the extensor hallucis longus), the extensor hallucis longus tendon is passed through the drill hole in the base of the proximal phalanx. It is pulled taut, and the hallux is brought into valgus. The tendon is sutured into the periosteum along the medial aspect of the proximal phalanx. At this point, the toe should be aligned in approximately 10 to 15 degrees of valgus. If the toe still tends to drift into varus, either the soft tissue contracture on the medial side was inadequately released or the extensor hallucis longus tendon was not placed under sufficient tension (see Fig. 8-15F and G ).
The remaining medial third of the extensor hallucis longus tendon is plicated by weaving a suture through it to place it under tension.
The skin is closed with interrupted suture in routine manner, and a compression dressing is applied postoperatively.
Alternative surgical techniques have been described to correct mild and moderate postoperative varus deformities. Lee et al and Choi et al have both described a distal metatarsal reverse chevron procedure in which the capital fragment is medialized to correct the varus deformity. Choi et al reported on 19 patients, of which 17 of 19 had a successful realignment ( Fig. 8-16 ). Leemrijse et al have proposed developing a slip of abductor hallucis medially and then routing in through a phalangeal drill hole and transferring this fascial slip back through a transverse metatarsal drill hole to create a stout lateral collateral ligament ( Fig. 8-17 ).
The postoperative dressing is removed and replaced with a snug gauze dressing and adhesive tape to hold the toe in a slightly overcorrected valgus position. The patient is permitted to ambulate in a postoperative shoe. The dressings are changed weekly for 8 weeks. A postoperative shoe should be used for another 2 weeks to allow further maturation of the tendon transfer ( Fig. 8-18 ).
This procedure will produce a satisfactory clinical result in about 80% of patients. On occasion, slight overcorrection or undercorrection of the MTP joint occurs but is usually well tolerated. Typically, 50% to 60% of MTP joint motion is maintained after this procedure ( Fig. 8-19 ). If little or no motion is present at the MTP joint preoperatively, the patient should be advised that this procedure will not significantly improve range of motion but will improve the overall position of the hallux. On occasion, minor skin slough develops in the skin along the medial side of the MTP joint, or delayed wound healing occurs because of the tension created by pulling the toe into a valgus position from its previous varus position. This is a challenging problem to mitigate since the medial incision cannot be placed in another location.
If the varus deformity develops after a resection arthroplasty (the Keller procedure), after excessive resection of the medial aspect of the metatarsal head, or in conjunction with MTP joint degenerative arthritis, MTP joint arthrodesis is the treatment of choice (see Chapter 7 ). Salvage with a silicone implant is contraindicated unless the deforming forces that led to the hallux varus deformity can be completely corrected. A joint replacement or silicone implant will maintain satisfactory joint alignment only if the surrounding soft tissues are well balanced.
A hallux varus deformity caused by nonunion of a metatarsal osteotomy is best corrected by MTP joint arthrodesis rather than an attempt at either tendon transfer or corrective metatarsal osteotomy. Although realignment osteotomy can occasionally be performed, complete balancing of the MTP joint soft tissues is crucial to obtain a successful and long-lasting correction.
To discuss complications of bunion surgery, it is important for the surgeon to approach bunion patients with a clear vision of the goals of treating hallux valgus deformities and of the technique(s) employed. The primary goal of bunion surgery is to produce the most functional and pain-free foot possible after surgery. This will vary, depending on the severity of the deformity and the functional capability of the patient. In a young patient with bunion pain secondary to a prominent medial eminence, a fully functional, painless foot is the goal; in a rheumatoid patient, a stable foot with satisfactory overall alignment that allows reasonable footwear and an ability to walk without pain is a realistic goal.
The algorithms that are found in Chapter 7 can help the clinician decide which type of surgical procedure will produce the best surgical results. However, following the algorithm does not inherently address a patient’s expectations. The patient and clinician must have a mutual understanding of the goals when surgery is being contemplated. It is not uncommon for an orthopaedic foot specialist to see patients in consultation who have been misled regarding their pervious surgery; even if the clinical result obtained was within the normal spectrum for a specific procedure, patients can express significant dissatisfaction. If patients are made aware of the various complications associated with each specific procedure (e.g., loss of motion, residual joint pain, sensitivity about the scar), although they may not be totally satisfied, at least they face no surprises. It is important to not “sell” a patient on a procedure but rather to be certain that the patient believes that all types of conservative management have been attempted and that surgery will offer a realistic solution to the problem. If the patient has no pain, it is difficult to improve the situation.
To a certain extent, each age group has specific goals for correction of a foot problem. With the wide selection of leisure and sport shoes available today, people can wear a shoe that will not place excessive pressure over the painful area. Several age groups have specific problems. For example, women in their second and third decade tend to have a higher level of dissatisfaction with the results of bunion surgery. Their goal is usually to be able to fit into a more stylish shoe, but many of these women have a wide forefoot, so even after satisfactory correction of the deformity, they are still unable to wear their desired shoes. If they believed that the surgery would permit them to do so, they will often be quite dissatisfied. This is basically a problem in preoperative communication between the surgeon and patient. An athlete or dancer, particularly if professional, should always receive the most conservative treatment plan possible. A general rule is that until such patients are significantly hampered in their ability to perform in their given profession, surgical intervention should be delayed because of the concern that after an unsuccessful surgical procedure, a painful foot will bring an end to their athletic career.
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