Hallux valgus inheritance: pedigree research in 350 patients with bunion deformity.

Our objective was to construct 3-generation pedigree charts from 350 patients with hallux valgus. During a 1-year period, all consecutive patients (n = 1174) with a painful bunion deformity evaluated roentgenographically were asked to complete a detailed 3-generation family history questionnaire. We studied 350 probands (22 men, 328 women; male/female ratio, 1:14.9; mean age, 47.8 years). Juvenile hallux valgus was diagnosed in 15 patients. Three or more affected members were observed in pedigrees from 244 probands, 2 affected members in 71, and 1 affected member in 35 (proband) (affected subjects per pedigree ranged from 1 to 16). Ninety percent of probands had at least 1 family member affected. The hallux valgus penetrance according to pedigrees from all probands was 56%. The female sex predominated with regard to the gender of parents with hallux valgus, affected branch of the family, and gender of relatives with bunion deformity. Severity of hallux valgus was not significantly influenced by gender, the affected branch of the family, or gender of the affected relatives. Family history of bunion deformity was present in 90% of probands, with vertical transmission affecting some family members across 3 generations, which is compatible with autosomal dominant inheritance with incomplete penetrance.