Dynamic First Tarsometatarsal Instability During Gait Evaluated by Pedobarographic Examination in Patients With Hallux Valgus.

Abstract

This study aimed to investigate the pedobarographic characteristics of tarsometatarsal instability and to identify factors associated with pedobarographic first tarsometatarsal instability in patients with hallux valgus. Fifty-seven patients (mean age, 59.7 years; standard deviation, 11.4 years; 6 men and 51 women) with a hallux valgus angle (HVA) greater than 15 degrees were included. All patients underwent a pedobarographic examination along with weightbearing anteroposterior (AP) and lateral foot radiography. Radiographic measurements were compared between the 2 groups with and without pedobarographic first tarsometatarsal instability. The association between the radiographic and pedobarographic parameters of the first tarsometatarsal instability was analyzed using the chi-square test. Binary logistic regression analysis was performed to identify significant factors affecting pedobarographic first tarsometatarsal instability. The HVA (<i>P</i> < .001), intermetatarsal angle (<i>P</i> = .001), and AP talo-first metatarsal angle were significantly different between the pedobarographically stable and unstable tarsometatarsal groups. There was no significant association between radiographic and pedobarographic instability of the first tarsometatarsal joint (<i>P</i> = .924). The HVA was found to be the only significant factor affecting pedobarographic tarsometatarsal joint instability (<i>P</i> = .001). The pedobarographic examination has possible clinical utility in evaluating first tarsometatarsal joint instability in patients with hallux valgus. Patients with a greater HVA should be assessed for the presence of first tarsometatarsal instability, and the necessity of the Lapidus procedure should be considered. Level III, comparative study.