Arthroscopic Fusion of the Great Toe

End-stage arthritis of the first metatarsophalangeal (MTP) joint

End-stage arthritis of the sesamoid to metatarsal head articulation

Disruption of the plantar plate

Gouty arthritis

A standing anteroposterior view of end-stage MTP joint arthritis is shown in Fig. 13.1 .

A standing lateral view of a patient with isolated MTP joint arthritis is shown in Fig. 13.2 .

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.

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

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

Anatomy of the first MTP joint from the dorsal side can be seen in Fig. 13.3 .

Anatomy of the dorsal portals is shown in Fig. 13.4 .

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

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.

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.