Repair of the central slip of extensor tendon and the open mallet using Mitek mini bone anchors

Abstract

There has been a recent upsurge in the use of bone anchors in repairing hand tendon injuries, which substantiates our use of Mitek anchors in the late 1990s with good results. The objective of this study was to describe our technique of using Mitek bone anchors to repair open mallet and open central slip avulsion injuries, hence evaluating their post-operative outcomes. Four patients with open mallet injury and ten patients with open central slip avulsions were treated using the Mitek mini bone anchors. In each case, the extensor tendon was shaved off its point of insertion on the middle or distal phalanx. All patients were operated in within 2 days of the open injury without any conservative measures pre-operatively. Post-operatively, the joint was maintained in an extension with a single trans-articular Kirschner wire or splint for 2 weeks, followed by gradual mobilization and active and passive exercises. Each patient underwent an objective evaluation to assess joint stability, the joint’s range of motion and grip strength compared to the uninjured side. Patients also underwent a subjective evaluation at the end of the follow-up period. The operative procedure was successful in all but one patient. One patient needed a relook procedure. Two patients were lost to follow-up, while the rest were followed up for a mean duration of 11 months (range = 5–24 months). Subjectively, two patients had excellent results, seven had good results, two had fair, and one achieved poor results. The Mitek bone anchor is a useful tool to treat open extensor tendon injuries, especially ones where the tendon has been shaved off at its insertion on the bone.