Cone arthrodesis of first metatarsophalangeal joint. A, Metatarsophalangeal joint is exposed through dorsal longitudinal incision just medial to extensor hallucis longus tendon. B, First metatarsal is prepared by insertion of guide pin down shaft and use of appropriate-sized female (concave) reamer to remove cartilage and expose subchondral bone. Care must be taken not to leave hallux too long if lesser metatarsal heads are removed. C, Proximal phalanx is prepared with different guide pin placed down shaft and corresponding-sized male (convex) reamer. D, Dorsal plate is used as guide for alignment of metatarsophalangeal joint arthrodesis and to place provisional Kirschner wire across joint for stability. E and F, After confirmation of appropriate alignment, contoured plate is secured with multi-use compression screws. SEE TECHNIQUE 85.2.