Risk factors for osteoarthrosis in the second and third tarsometatarsal joints in patients with hallux valgus.

Background: Hallux valgus (HV) is prevalent in older adults and often coexists with osteoarthrosis (OA) of the second and third tarsometatarsal (TMT) joints, leading to functional impairment. Because OA changes in these joints are irreversible, understanding factors influencing OA is critical for improving therapeutic strategies. This study aimed to identify the factors influencing second and third TMT OA development.

Methods: This retrospective study included 108 feet with HV. Patients were divided into the OA group (33 feet) and the non-OA group (75 feet) according to the complaint of their pain in the dorsum of the foot. Clinical data and radiographic parameters such as the HV angle (HVA), intermetatarsal angle (IMA) and M1M5 angles, Meary angle, calcaneal pitch angle, and first TMT angle, and metatarsal length were analyzed. Logistic regression was used to identify factors associated with OA in the second and third TMT joints.

Results: In the OA group, age, body mass index (BMI), HVA, IMA, M1M5, 1st TMT, Meary, and CP angles were significantly higher, and the M3/M1 and M4/M1 ratios were significantly lower than those in the non-OA group. Logistic regression identified body mass index (BMI) (p < 0.01), age (p < 0.05), Meary angle (p < 0.01), and M4/M1 ratio (p < 0.05) as significant predictors of OA.

Conclusion: Degeneration of the second and third TMT joints was associated with the severity of HV and correlated with structural deformities such as reduced medial longitudinal arches. Identifying key factors such as BMI and radiographic parameters can provide insights into the pathogenesis of HV-related TMT-OA and provide targeted therapeutic interventions.

Level of evidence: 4: