Metatarsalgia in hallux valgus deformity: A pedographic analysis

The purpose of this study was to analyze the plantar loading patterns in patients with hallux valgus (HV) with and without symptoms of metatarsalgia in order to find predictive pressure variabilities which are likely to result in metatarsalgia. Two groups of subjects (100 feet) volunteered for this study. Both groups provided the diagnosis of HV deformity. Group A (50 feet) exhibited a metatarsalgia symptomatology, whereas group B was asymptomatic. Plantar loading patterns were assessed using the two-step method and data were collected by the use of a capacitive pressure measurement platform. For each patient, 10 acceptable trials were collected. For the analysis, the foot was divided into six plantar regions: heel, midfoot, medial forefoot, lateral forefoot, medial toe, and lateral toe. Maximal peak pressure (PP, N/cm²), pressure-time integral (PIT integral, N/cm^2*s), and force-time integral (%) were calculated. In group A, loading patterns (PP, PIT integral) of the lateral forefoot were significantly higher than in group B. The mediolateral pressure transfer from the big toe to the lateral metatarsal region was significantly greater in group A compared to group B. Regarding the lateral forefoot, a pressure time integral <10 N/cm^2* s was indicative of asymptomatic HV feet, whereas in symptomatic HV feet, a pressure time integral >28 N/cm^2* s was observed. These results were statistically significant at the p < .01 level.