Arthroscopy of the Great Toe

Loose bodies

Hallux valgus: synovitis

Hallux valgus: lateral release

Turf toe: assessment of plantar plate

Sesamoid to metatarsal head arthritis

Gout

Dorsal osteophytes

Hallux rigidus

Chondral defect

Arthroscopic first metatarsophalangeal (MTP) fusion

Synovitis

Diagnostic arthroscopy for recurrent pain or swelling localized to the MTP joint

Arthrofibrosis

Osteochondral defects

Pigmented villonodular synovitis

Ganglion excision

A standing anteroposterior view of a dorsal osteophyte is shown in Fig. 8.1 .

A standing lateral view of a dorsal first MTP osteophyte is shown in Fig. 8.2 .

Patients are observed standing with both feet bare. The forefoot alignment is inspected, as well as hallux valgus deformity. Claw toes may indicate lesser toe overload.

The gait pattern is observed. Patients may walk on the lateral border of the foot to avoid weight on a painful first MTP joint.

Patients may not be able to walk on tip toes because of MTP joint pain or loss of dorsiflexion range.

Inspection may demonstrate a callus under the interphalangeal (IP) joint because of loss of range of motion.

The first ray may be unstable because of ligament laxity. This may cause elevation of the first ray and failure of weight bearing through the sesamoids.

Range of motion is measured with a goniometer and compared with the opposite side. The range of motion is also measured at the IP joint level.

The sesamoids are palpated to determine if they are a source of discomfort.

The flexor and extensor tendons are tested for integrity.

The neurovascular examination is performed.

Imaging should include a standing anteroposterior and lateral view of the foot, and on occasion a sesamoid view.

Magnetic resonance imaging can be useful for assessment of the sesamoids and articular surfaces.

A computed tomography scan can be of value in assessing osteophyte anatomy and joint space narrowing.

Rocker sole shoe

Rigid sole shoe with a rocker

Orthotic with a metatarsal pad, or a Morton’s extension for an elevated first ray

Orthotic with a metatarsal head cut out for metatarsal head overload

Medical management of gout

Physiotherapy and gait training

Local anesthetic and steroid injection into the MTP joint

Topical or oral antiinflammatories

Anatomy of the first MTP joint from the dorsal side can be seen in Fig. 8.3 .

Anatomy of the dorsal portals is shown in Fig. 8.4 .

First MTP joint arthroscopy is relatively easy to perform from the dorsal side in a mobile joint.

The joint space not only includes the proximal phalanx and metatarsal head but also the two sesamoid to metatarsal head articulations that can be visualized during the procedure.

The extensor hallucis longus provides the landmark for the dorsal medial and dorsal lateral portals.

The joint margin can usually be palpated from the dorsal side. The thumb of the left hand is used to feel for the joint margin, while the right hand grasps and pulls the phalanx to open the joint. Dorsiflexion and plantar flexion range will also allow the bone margins to be felt.

Structures at risk are illustrated in Fig. 8.4. The dorsal medial and dorsal lateral nerves are variable in location and anatomy, hence the need for blunt dissection within the subcutaneous space where the nerves lie.

The plantar medial and plantar lateral nerves lie in a deeper plane and next to the sesamoids. As they are on weight-bearing surfaces, damage to these nerves can result in considerable disability. However, they are a distance away from any likely portal placement.

The short flexor tendons insert into the medial and lateral sesamoids. The flexor hallucis longus passes between the sesamoids in a flexor sheath and passes distally under the phalanx. The short flexors insert distal to the sesamoids by two tendons (a medial and lateral) into the base of the proximal phalanx. They form part of the plantar plate that stabilizes the MTP joint.