Metatarsus primus varus occurs in feet which have a normal 1--2 intermetatarsal angle. Fifty-two Caucasian females, average age 18 years, were analyzed radiologically for 1--2 and 1--5 intermetatarsal angles and for metatarsophalangeal and first interphalangeal joint angles. Measurement of the 1--5 rather than the 1--2 intermetatarsal angel is a more reliable indicator of first metatarsal varus. Valgus at the first interphalangeal joint is normally greater than that at the first metatarsophalangeal joint and excessive first interphalangeal valgus (valgus interphalangeus) is significantly linked with the presence of ossia tibiale externa. The high arch foot tends either to feature valgus interphalangeus or become excessively broad. The anatomy of the ungual tuberosity is highly variable.
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