Second Metatarsal Length and Transfer Ulcers After First Metatarsal Amputation in Diabetic Foot Infections

Area of Science:

• Podiatry
• Diabetic Foot Care
• Surgical Outcomes

Background:

• Plantar transfer ulcers (TUs) are common after first metatarsal ray amputations in diabetic patients.
• The association between second metatarsal length (2ML) and TU occurrence is not well understood.
• This study investigates the role of 2ML in TU development post-amputation.

Purpose of the Study:

• To determine if 2ML is associated with TU occurrence after first metatarsal ray amputations.
• To assess if patients with "excess" 2ML have shorter ulcer-free survival.
• To identify risk factors for TUs in this patient population.

Main Methods:

• Retrospective comparative study of 42 diabetic patients with first metatarsal ray amputation.
• Second metatarsal length (2ML) measured using the Coughlin method; "excess" 2ML defined as >4.0 mm protrusion.
• Multivariate Cox regression and Kaplan-Meier survival analysis used to evaluate 2ML and ulcer occurrence.

Main Results:

• TUs occurred in 15 (36%) patients.
• 2ML was not significantly different between patients with and without TUs (mean 5.3 mm vs. 4.0 mm).
• Insulin dependence, not 2ML, was significantly associated with ulcer occurrence (HR 0.33).

Conclusions:

• In this study, second metatarsal length (2ML) was not significantly associated with plantar transfer ulcer (TU) occurrence.
• Ulcer-free survival was similar for patients with normal and "excess" 2ML.
• Further research with larger cohorts is needed to confirm these findings.