The effect of releasing critical pulleys of the fibrous sheath during flexor tendons repair in Kleinert–Verdan Zone II: a review

The fibrous flexor tendon sheath is a relatively thick structure surrounding both flexor tendons (superficial and profundus) along the finger and distal part of the metacarpus. It consists of circumferentially and obliquely passing bands, so-called ‘pulleys’. The flexor tendon fibrous sheath with its pulley system plays an important role in the proper gliding of the tendons by maintaining them close to the bone of phalanges during full finger flexion, and its major defects manifest by impaired flexion of the finger because the tendon bowstringing. There is no commonly accepted opinion about the range of pulley release which is safe and would not cause bowstringing. The article presents current recommendations about the safe range of release of pulleys during repair of the flexor tendons which essentially allows longer incisions than was suggested previously. The priority is the undisturbed gliding of repaired tendon along the finger and avoiding catching the repair at edge of the pulley, which would result in a reduction of the finger’s range of motion.