Flexor tendon repair in zone II of the hand: Evidence-based management

Abstract

Introduction: Flexor tendon injuries require precise surgical repair followed by rehabilitation to ensure optimal recovery and reduce the risk of complications such as tendon rupture, scarring and adhesions. Zone II flexor tendon injuries, which are located between the flexor digitorum superficialis insertion and the A1 pulley, are particularly challenging due to the complex anatomy and the high risk of complication, earning it the nickname "no man's land".

Material and methods: This systematic review was conducted in accordance with the principles of evidence-based medicine (EBM), which involve formulating a clinical question, searching for relevant studies, and critically appraising the quality of the evidence. This included evaluating study design, methods, sample size, and bias. Recommendations were made based on the strength of evidence and the impact of bias. This review addressed eight key questions concerning the diagnosis, repair, and rehabilitation of zone II flexor tendon injuries. Three review authors independently examined the titles and abstracts of the references retrieved from the searches, selecting all those that were potentially relevant.

Results: Imaging still plays a limited role in diagnosis. Up to an unknown percentage of partial tears may be treated conservatively when comparable stringent rehabilitation principles are used. WALANT technique is not superior. Repair requires a four-strand or multi-strand core suture, with or without an epitendinous suture. Judicious pulley venting is safe and effective. The cornerstone of effective post-operative management in zone II flexor tendon injuries is early controlled mobilization, either passive or active, based on the strength of the repair and patient adherence. Combining this approach with structured therapy and vigilant follow-up is associated with improved range of motion, minimized adhesion formation and optimal functional outcomes in clinical practice.

Level of evidence: V.

Keywords: Digit zone II; Evidence-based medicine; Flexor tendon; Literature review; Rehabilitation; Repair.