Natural Progression of Radiographic Indices in Juvenile Hallux Valgus Deformity

Category: Bunion, Midfoot/Forefoot Introduction/Purpose: There is a lack of quantitative studies on the progression of juvenile hallux valgus deformity. Therefore, we performed this study to estimate an annual change of radiographic indices for juvenile hallux valgus. Methods: We reviewed medical records of consecutive patients under the age of 15 with juvenile hallux valgus who underwent weight-bearing foot radiographs more than twice, and were followed over a period of one year or more. A total of 133 feet from 69 patients were included. Hallux valgus angle, hallux interphalangeal angle, intermetatarsal angle, metatarsus adductus angle, distal metatarsal articular angle, anteroposterior talo-1st metatarsal angle, anteroposterior talo-2nd metatarsal angle, and lateral talo-1st metatarsal angle were measured and were used as a study criteria. The progression rate of hallux valgus angle was adjusted by multiple factors including the use of a linear mixed model with gender and radiographic measurements as the fixed effects and laterality and each subject as the random effect. Results: Our results demonstrate that the value of hallux valgus angle on the radiographs progressed as the patients grew older. The hallux valgus angle increased by 0.8° per year (p<0.001)(Figure). The distal metatarsal articular angle also increased by 0.8 per year (p=0.003). Conversely, hallux interphalangeal angle decreased by 0.2° per year (p=0.019). Progression of the intermetatarsal angle and metatarsus adductus angle with aging were not statistically significant. There was a difference in progression of radiographic indices between older patients (=10 years) and younger patients (<10 years). The hallux valgus angle increased by 1.5° per year (p