Correlation between generalized joint hypermobility and hallux valgus

Abstract

Purpose: to evaluate correlation between generalized joint hypermobility, forefoot deformities and elasticity of the first ray of the foot. Material and methods. We examined 138 patients with complaints related with deformities at the forefoot level. During this study the medical history was obtained, the elasticity type of the feet was defined and the degree of motion of the medial metatarsal-cuneiform joint was evaluated. Forefoot elasticity was identified by bringing together the heads I and V metatarsal bones with fingers. If convergence occurred with little resistance, those feet were called hyperelastic. The convergence of the heads I and V metatarsal bones of the foot with an average type of elasticity occurred with resistance. It was impossible to converge the heads of I and V metatarsal bones. Due to the results of weight-bearing and non-weight bearing X-ray, analysis of the main radiographic angles of the foot was performed: between I and V metatarsal bones, between the first and second metatarsal bones and between the first metatarsal bone and proximal phalanx of the great toe. Calculation formula of the forefoot flatness index, showing the average ratios of basic radiographic angles of the foot on the x-ray images (weight-bearing and non-weight bearing) was created. An assessment of total joint hypermobility using Beighton scale and evaluation of first ray deformity using DuPont scale were performed. Statistical analysis of obtained data was performed, as a result of which significantly strong correlation between total joint hypermobility, forefoot elasticity and valgus deviation of the great toe were revealed. Results. 11% of the feet were hyperelastic. Calculation of the index of forefoot flatness showed that forefoot flatness wasn’t significant for a rigid foot - 5.6 %, for the feet with an average degree of mobility it was 6.0% and it was expressed for hypemobile feet - 12.3 %. Strong correlation relation between the forefeet mobility degree, the number of points on a DuPont scale and the degree of sagittal mobility of the medial metatarsal-cuneiform joint were revealed. Conclusion. Our study demonstrates that generalized joint hypermobility, horizontal and sagittal first ray mobility and forefoot deformities are directly proportional.