Medial deviation of the first metatarsal in incipient hallux valgus deformity.

BACKGROUND The aim of this study was to determine whether excessive medial deviation of the first metatarsal (excessive intermetatarsal angle) is present in the initial phase of hallux valgus. METHODS The intermetatarsal angle between the first and second metatarsals (1-2 IMA) was radiographically studied in 49 normal feet and in 49 feet with mild hallux valgus deformity. RESULTS The results demonstrated a statistically significant difference in the mean intermetatarsal angle between the two groups (8.76 degrees in normal feet; 9.98 degrees in affected feet). However, we believe that is not clinically significant. Other authors, comparing the 1-2 IMA in patients with or without more advanced hallux valgus, reported greater differences than those obtained in this study. CONCLUSIONS Excessive medial deviation of the first metatarsal is not a causal factor but rather a consequence of hallux valgus deformity.