The Emergency Physician (EP) commonly encounters lacerations or trauma to the dorsum of the hand and forearm. In evaluating these patients, the possibility of extensor tendon lacerations must be considered. The extensor mechanism of the hand and forearm is typically disrupted in association with penetrating trauma. It must be remembered, however, that blunt trauma, such as sudden forced flexion, can also result in injury to the extensor tendons. Performing an extensor tendon repair is an important skill in the EP's surgical armamentarium.
Although the diagnosis of an extensor tendon injury must be identified at the initial examination, the timing of the tendon repair is not a critical aspect of its management. Successful repair of extensor tendons may be accomplished acutely, or within a 7 day window following the injury.1 One should also be aware that at some anatomic sites, splint immobilization of the damaged tendon can produce a similar outcome to surgical reapproximation. This is most evident in the conservative management of a mallet finger injury.
Repair of an extensor tendon by an EP requires them to have a familiarity with the anatomy of the region and be skilled in the surgical technique. Although complications of tendon repair are more frequently associated with flexor tendons, follow-up studies of extensor tendon repairs reveal similar pitfalls and problems.2 Adhesions, loss of length, and diminished flexion can all complicate the repair of an extensor tendon.3
The anatomy of the extensor mechanism prevents tendon retraction far from the site of a laceration or partial disruption.4 This is mostly due to the tethering of tendons by multiple interconnections as the tendons cross the dorsum of the hand. Additionally, the tendons over the dorsum of the hand are ensheathed in a paratenon layer of tissue. This covering is extrasynovial, thus containing the cut ends of the tendons in a tissue layer that prevents their wide separation. These properties frequently allow both ends of a lacerated extensor tendon to be located with local wound exploration, at which point they may be safely repaired.
The techniques for extensor tendon repair originate in studies of flexor tendons. The goal of extensor tendon repair is to restore tendon continuity and function while minimizing interference from the repair itself. The suture techniques of Kessler and Bunnell are two of the methods traditionally used in this repair. Modifications of these original methods have resulted in the greatest outcome measurements of tendon strength.5 Facility with these two suture techniques, as well as the anatomy, is essential to the repair of any extensor tendon in the Emergency Department (ED).
The extensor tendon mechanism is an intricate system of pulleys and levers coursing along the dorsum of the forearm, wrist, and hand.6,7 The function of these tendons is to extend the fingers and wrist from a flexed position. This finger motion is complemented by the actions of the intrinsic ...