A critical analysis of Dudley Morton's concept of disordered foot function.

The name Morton is associated with a foot structure characterized by a short first metatarsal in comparison with the adjacent second metatarsal. Dudley Morton is credited with recognizing a short first metatarsal as being a primary defect of the foot. Morton, an anatomist, approached his observation from an evolutionary perspective. His theory of disordered foot function was based on the premise that human alignment centered on an "axis of leverage" and around an "axis of balance." Morton concluded that the presence of a short first metatarsal was compounded when the first metatarsal segment was hypermobile. Shortness and hypermobility diminished the capacity of the first metatarsal segment to carry weight, allowed pronation during activity, and led to an overload of the central metatarsals. The term Morton Foot sprang from his teachings. The extensive writings of Morton are commonly cited even today. This study compares Morton's teachings with research published during the last 70 years, which either supports or refutes his claims.