Anatomic variations in the first ray: Part II. Disorders of the sesamoids.

Cadaveric and fresh amputation dissection studies revealed that condylar anomalies, metatarsal axial rotation, and bowstrung flexor tendos will commonly produce subluxation and degenerative changes at the metatarsophalangeal-sesamoid joint. The average arc of motion of the sesamoids from maximum plantar- and dorsiflexion was measured at 71.9 +/- 11 degrees. The anatomic variations presented are correlated with the incidence of chronic sesamoiditis, painful bipartite sesamoids, and chronic nonunions.