24 - Flexor tendon injury and reconstruction

Abstract

■Tendons transmit forces generated by muscles to move joints or to create action power. Flexor tendon injuries are common, but recovery of satisfactory function, particularly after injuries within the digital sheath, is sometimes difficult. Lacerated flexor tendons should be treated by primary surgical repair whenever possible.■The current trend of end-to-end surgical tendon repairs is to use multistrand core sutures (four-strand repairs such as cruciate, double-Tsuge, Strickland, and modified Savage, or six-strand repairs such as modified Savage and Tang).■In tendon repairs in the digital sheath area, a number of surgeons advocate that the A2 pulley can be released up to two-thirds of its length, the A4 pulley can be entirely released when necessary, and tendon repair is in the proximity of the pulley, given the integrity of the other pulleys. The release may reduce the resistance to tendon motion and the chance of repair ruptures. This technique is somewhat controversial.■Postoperatively, early tendon mobilization should always be employed, except in children or in some rare instances; motion protocols vary greatly among different treatment centers.■Repair ruptures, adhesion formations, and finger joint stiffness are major complications of primary surgery.■Combined use of multistrand core repairs, release of constricting pulley parts, and well-designed postoperative combined passive and active motion protocols – that do not overload, but sufficiently move the tendon – can help minimize adhesions, avoid repair ruptures, and restore optimal function.■Secondary surgeries include tenolysis, free tendon grafting, and staged tendon reconstruction. Tenolysis is indicated when restricting adhesions hamper tendon gliding and soft tissues and joint conditions of the hand are favorable. Free tendon grafting is a salvage operation for failed primary repairs, delayed treatment (>1 month) of an acute cut, or lengthy tendon defects. Staged reconstruction is indicated in cases of extensive scar formation or multiple failed surgeries. Preservation or reconstruction of major annular pulleys is vital to restoring function of the digits during these secondary surgeries.■Closed ruptures of flexor tendons usually require surgical repairs.■The success of flexor tendon surgeries is very expertise dependent. A thorough mastery of anatomy and meticulous surgical techniques are requirements for satisfactory restoration of function.