Strength and functional recovery following repair of flexor digitorum superficialis in zone 2.

A two-pronged study was designed to evaluate the strength in vitro and functional recovery in vivo of FDS repairs in zone 2. In part I, horizontal mattress or Tajima grasping repairs were performed on fresh-frozen cadaveric digits, using 3/0 or 4/0 braided nylon suture material. The Tajima repair was significantly stronger than the mattress suture, using either 3/0 (P = 0.0001) or 4/0 (P = 0.0027) suture material. The 3/0 Tajima repair appeared strong enough to permit gentle early active motion. Furthermore, the clinical portion of the study (part II) demonstrated restoration of FDS function following repair in relatively isolated injuries in 13 out of 15 digits (86.7%), with PIP flexion averaging 80 degrees and grip strength 89% of that in the uninjured hand.