Extramembranous and Interosseous Technique of Tibialis Posterior Tendon Transfer

Overview

Foot drop deformity is a life limiting condition characterized by loss of ankle dorsiflexion and eversion. Main condition leading to drop foot condition include irrecoverable muscle and nerve injuries, poliomyelitis, drug poisoning, strokes, cerebral palsy, Charcot - Marie - Tooth disease, meningomyelocele, club foot, Friedreich's ataxia and Leprosy (1-4). Anterior transposition of Posterior tibialis tendon (PTT) is the gold standard for surgical restoration of functional dorsiflexion of a permanently paralyzed foot (1, 4-10). Two methods of rerouting the posterior tibialis tendon have been reported, one through the interosseous membrane i.e. Interosseous route (7, 10) and second subcutaneously around the medial side of tibia i.e. Extramembranous or circumtibial route (11-13). Both these techniques have been widely described in literature (4-16) and are being extensively used in surgical management of foot drop. The selection of technique depends on surgeon choice and patient factors. There is a clinical equipoise with regards to these two techniques of Tibialis posterior tendon transfer and through our study we aim to compare the clinical and functional outcomes of these two techniques. There are no studies in literature which compare the clinical and functional outcomes with regards to both these methods. Although there are many studies to demonstrate the functional and clinical effectiveness of the respective procedures, there is a paucity of clinical trials comparing these two surgical techniques with regards to clinical and functional outcomes. Furthermore there are no head to head clinical trials to compare the outcomes with regards to these two methods of Tibialis Posterior tendon transfer (Medline search dated 03/03/ 2012) we propose to compare the clinical and functional outcomes with regards to the two techniques i.e extra membranous and Interosseous technique of Tibialis Posterior tendon transfer performed in patients with foot drop as a result of nerve palsy. Through our prospective randomized trial we aim to answer the research question, whether one method has any superior outcome over the other?

Foot drop deformity is a life limiting condition. This has far reaching consequences in patients of all age groups. Anterior transfer of tibialis posterior tendon is now regarded as the gold standard treatment as this allows walking without wearing an orthosis and thus substantial improvement in quality of life. This equally applies to developing and developed world. The rationale for our study is that that there is a clinical equipoise with regards to these two techniques of Tibialis posterior tendon transfer and through our study we aim to compare the clinical and functional outcomes of these two techniques. Both these techniques have been widely described in literature (References attached) and are being extensively used in surgical management of foot drop. The selection of technique depends on surgeon choice and patient factors. There are no studies in literature which compare the clinical and functional outcomes with regards to both these methods. Although there are many studies to demonstrate the functional and clinical effectiveness of the respective procedures, there is a paucity of clinical trials comparing these two surgical techniques with regards to clinical and functional outcomes. Furthermore there are no head to head clinical trials to compare the outcomes with regards to these two methods of Tibialis Posterior tendon transfer (Pub med search dated 12/03/2012) This study is of great interest to health care professionals managing foot drop both in developing and developed world. The answer to our research question; whether one surgical technique has better clinical, functional and quality of life over the other, will greatly impact the future surgical management of foot drop.