Physical Address
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Core Procedures
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Joint fusion
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Joint replacement
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Arthroscopic procedures
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Joint release
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Ligament repair
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Tendon debridement, repair and transfer
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Osteotomy
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Fracture
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Contracture release
Surgical surface anatomy
The dorsal surface of the foot has a smooth, convex outline, which inclines gradually laterally and rapidly medially from a summit formed successively by the head of the talus, the navicular, the intermediate cuneiform and the second metatarsal. The head of the talus forms a rounded projection in front of the ankle joint when the foot is forcibly dorsiflexed. On the medial side of the foot, the medial process of the calcaneal tuberosity and sustentaculum tali are palpable. The tuberosity of the navicular is palpable about 2.5–3.0 cm anterior to the medial malleolus.
Further forwards, the ridge formed by the base of the first metatarsal can be felt and the body of the bone can be traced to its expanded head. The medial sesamoid of the hallux is beneath the base of the proximal phalanx. On the lateral side of the foot, the most posterior bony point is the lateral process of the calcaneal tuberosity. The greater part of the lateral surface of the calcaneus is subcutaneous; if present, the trochlear process can be felt here, below and anterior to the lateral malleolus. Further forwards, the base of the fifth metatarsal is prominent, and the body and head of the bone can be traced distally. As is the case with the metacarpals, the dorsal surfaces of the metatarsals are easily palpated; their heads do not form prominences because their plantar surfaces are obscured by muscles and other overlying soft tissues ( 
). The phalanges are readily palpable throughout their whole extent.
The tendons that spread out on the dorsum of the foot, from medial to lateral, are those of tibialis anterior (most medial and largest), extensor hallucis longus, extensor digitorum longus (to the second, third, fourth and fifth toes), and fibularis (peroneus) tertius. Extensor digitorum brevis produces a rounded mound on the dorsum of the foot with fullness anterior to the lateral malleolus. Dorsal interossei bulge between the metatarsals.
Clinical anatomy
Bones and joints
The hindfoot consist of the talus and calcaneus ( Figs 86.1 and 86.2 ; see Fig. 85.3 ). The subtalar joint has three points of contact (facets) with the calcaneus and is involved with inversion and eversion of the foot. The posterior facet is the largest, the middle facet is located medially and the anterior facet is continuous with the talonavicular joint. In conjunction with the subtalar joint, the transverse tarsal joint (Chopart's joint) contributes to foot flexibility during the gait cycle. The calcaneonavicular joint is supported by the plantar calcaneonavicular (spring) ligament, a complex connecting the sustentaculum tali of the calcaneus to the plantar aspect of the navicular and supporting the head of the talus as part of the talocalcaneonavicular joint ( Fig. 86.3 ). The calcaneocuboid joint is saddle-shaped and is supported by the dorsal and plantar calcaneocuboid ligaments; the lateral limb of the bifurcate ligament (Chopart's ligament; composed of the calcaneonavicular and calcaneocuboid ligaments) provides superior restraint. Inversion of the subtalar joint locks the transverse tarsal joint and allows for a stable hindfoot/midfoot for toe-off. Eversion of the subtalar joint unlocks the transverse tarsal joint to allow the supple foot to accommodate to the ground just after heel strike. The plantar aponeurosis allows for load/force transfer between the hindfoot and forefoot during ambulation.
The midfoot begins at the articulation between the navicular and cuneiforms, and consists of articulations between the cuboid and fourth and fifth metatarsals. Midfoot joints include the naviculocuneiform, intercuneiform and tarsometatarsal (Lisfranc's) joints. The latter consists of the first, second and third metatarsocuneiform joints and the fourth and fifth metatarsocuboid joints. The ligamentous support of the tarsometatarsal joint consists of an interosseous layer (the strongest layer), which contains Lisfranc's ligament, originating from the plantar aspect of the medial cuneiform and inserting on to the base of the second metatarsal; a plantar layer, which is less strong; and a dorsal layer, which is the weakest layer.
The midfoot is divided into three columns: a medial column comprising the first metatarsal, medial cuneiform and navicular; a middle column comprising the second and third metatarsals and middle (intermediate) and lateral cuneiforms; and a lateral column composed of the fourth and fifth metatarsals and cuboid. The medial column carries most of the load during standing. The middle column is the least mobile and allows for rigidity during push-off. The lateral column is the most mobile of the three columns and allows for flexibility when walking on uneven ground.
The forefoot extends from the tarsometatarsal joints to the tips of the toes. The first metatarsal is the shortest and widest, and carries 50% of the weight during the gait cycle. The second metatarsal is the longest. The joints of the forefoot include the metatarsophalangeal and the proximal and distal interphalangeal joints. The deep transverse metatarsal ligament holds the sesamoids of the hallux in place as the head of the first metatarsal moves medially. The tendon of adductor hallucis has a broad insertion over the lateral aspect of the lateral sesamoid and lateral aspect of the base of the proximal phalanx. The plantar plate is made up of a dense phalangeosesamoidal complex: it must be lax before abnormal dorsal translation of the proximal phalanx can occur.
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