First Metatarsal Head and Medial Eminence Widths with and Without Hallux Valgus.

BACKGROUND: Resection of the medial eminence in hallux valgus surgery is common. True hypertrophy of the medial eminence in hallux valgus is debated. No studies have compared metatarsal head width in patients with hallux valgus and control patients.

METHODS: We reviewed 43 radiographs with hallux valgus and 27 without hallux valgus. We measured medial eminence width, first metatarsal head width, and first metatarsal shaft width in patients with and without radiographic hallux valgus.

RESULTS: Medial eminence width was 1.12 mm larger in patients with hallux valgus (P < .0001). Metatarsal head width was 2.81 mm larger in patients with hallux valgus (P < .001). Metatarsal shaft width showed no significant difference (P = .63).

CONCLUSIONS: Metatarsal head width and medial eminence width are significantly larger on anteroposterior weightbearing radiographs in patients with hallux valgus. However, frontal plane rotation of the first metatarsal likely accounts for this difference.