Tibialis Posterior Transfer for Foot Drop: The Difference in Outcome for Two Different Attachment Sites

Introduction Common peroneal nerve injury leading to foot drop is of multifactorial etiology. The goal is to restore a normal toe-heel gait. Various static or dynamic surgical options are being performed. Among all, tendon transfer is the most commonly performed procedure with its different dorsal attachment sites on the foot i.e. tendon to bone or tendon to tendon transfer. The objective of our study was to evaluate the outcomes of two methods of transfer in terms of attachments sites on functional outcomes. Materials and methods In a retrospective study conducted at Liaquat National Hospital Karachi, a total of 38 patients were included. All of them were operated upon for foot drop from June 2015 to May 2018. A total of 32 patients showed up for the follow-up, 17 patients underwent tibialis posterior transfer with attachment on the second metatarsal and 15 on the tibialis anterior tendon. Functional outcome was assessed by grading of active foot dorsiflexion at six months and at the time of the study by and categorized as excellent, good, moderate, and poor. Results Most of the patients in both groups were male, and the mechanism of injury was penetrating trauma. At six months post-operatively, the majority of the patients in both groups showed excellent to good category of active dorsiflexion. At the time of the study (mean 34.4 months postoperatively) patients with insertion at second metatarsal were found to have active dorsiflexion as: excellent: 6 (35.3%), good: 8 (47.1%), moderate: 3 (17.6%), and for insertion at Tibialis Anterior tendon: excellent: 1 (6.7%), good: 6 (40.0%), moderate: 6 (40.0%) and poor: 2 (6.2%). These results were compared using the chi-square test and it was found to be statistically significant (p-value: 0.016). Conclusion Insertion at second metatarsal gives more favorable results as compared to insertion at tibialis anterior with balanced dorsiflexion.