Brachymetatarsia: A Classification for Surgical Treatment

Abstract

Brachymetatarsia is a congenital osseous and soft tissue deformity of a ray(s) of the foot. Because there is no particular consensus of methodology of lengthening for brachymetatarsia, the authors introduce a comprehensive anatomic classification and a surgical guide to treatment of each classification type. This classification combines the number of the metatarsal(s) affected and the letter(s) indicating the type of brachymetatarsia deformity (A = axial deficiency of the metatarsal, B = bowing of the metatarsal, C = congruency of metatarsal phalangeal joint). This study reviewed of 300 brachymetatarsals in 166 patients. Fifty of the 166 (30%) patients had bilateral brachymetatarsia. Of the 300 metatarsals with brachymetatarsia, 64 (21%) were first metatarsals, 22 (7%) were second metatarsals, 28 (9%) were third metatarsals, 12 (4%) were fifth metatarsals, and 174 (58%) were fourth metatarsals. Classification types that were found was a total of 165 (55%) type A, a total of 6 (2%) type B, a total of 72 (24%) type AB, a total of 39 (13%) type AC, and a total of 18 (6%) type ABC. A total of 16 (10%) male and 150 (90%) female patients were evaluated. The mean preoperative amount of shortening of the metatarsal was 15 mm (range, 4-20 mm), as determined by the preoperative metatarsal parabola deficiency, equating to 30% of the preoperative metatarsal length. Brachymetatarsia is a complex congenital deformity which until now has not been critically analyzed. This study outlines a comprehensive brachymetatarsia classification system which provides an accurate diagnosis of the deformity and offers a surgical treatment algorithm.