Direct Flexor Tendon Repair More than 3 Months After Trauma: Clinical Outcomes of Four Consecutive Cases and Scoping Review on Time Limits

<b>Background/Objective:</b> Traumatic injuries to the flexor tendons of the hand are frequently treated by hand surgeons. Late repair is not classically considered to be feasible due to the high risk of failure and functional complications. The present study aims to present the functional results of primary flexor tendon repairs performed more than three months after trauma, along with evidence regarding the time limit for primary flexor tendon repair. <b>Methods:</b> The clinical outcomes of direct flexor tendon repairs in zones 1 and 2 of the long fingers or thumb are reported herein. A scoping review was undertaken using Medline and CINHAL to identify studies reporting the functional outcomes of flexor repair following trauma. <b>Results:</b> In this series, four patients were treated with direct M-Tang and epitendinous suture or pull-out reinsertion. Accessory procedures were required to perform a direct repair. The mean delay was 5.5 months, and the follow-up period was 24 months. The mean total active movement was 195°. Extension lags of 10° and 20° were registered at the proximal interphalangeal and distal interphalangeal joints, respectively. While a literature review showed that most cases treated with primary repair after three months resulted in functional complications, these procedures were performed around 40 years ago and no recent reports were found. <b>Conclusions:</b> In the small cohort of patients here reported it has been possible to repair flexor tendons in zones 1 and 2, and to reinsert a jersey finger, even three months after trauma. Accessory procedures were required. Accurate patient selection and counseling is mandatory before surgery to inform patients about alternatives. The literature review confirmed that no positive results have previously been reported in the literature on this topic. It is thought that modern materials and surgical techniques for flexor tendon repair should extend the edge for primary repair in selected patients, as compared to previous practices.