Usefulness of Wide-Awake Local Anesthesia No Tourniquet Surgery to Decide on Tendon Transfer Versus Grafting in Chronic Flexor Tendon Rupture

PURPOSE: We investigated the clinical outcomes of flexor tendon reconstruction for chronic rupture of the flexor tendon based on an evaluation of the voluntary active contraction distance (ACD) of the ruptured musculotendinous unit and changes in intraoperative total active motion (TAM) that could only be observed during wide-awake local anesthesia no tourniquet (WALANT) surgery. METHODS: Reconstructions of 19 tendons of the flexor pollicis longus (FPL) and 18 tendons of the flexor digitorum profundus (FDP) were performed during WALANT surgery to evaluate the ACD of the ruptured musculotendinous unit and TAM observed during the surgery. Tendon grafting or tendon transfer was selected during the surgery based on ACD. TAM, pinch strength, and grip power were evaluated before the surgery, during the surgery, and at final follow-up, and they were surveyed based on Quick Disabilities of the Arm, Shoulder, and Hand (q-DASH) scores. The final outcomes of tendon grafting and tendon transfer were compared. RESULTS: In FPL tendon reconstruction, tendon grafting was performed in 10 patients with a total PDD and ACD value greater than 30 mm, and tendon transfer was performed in 9 patients with the value less than 30 mm. In FDP tendon reconstruction, tendon grafting was performed in 8 patients and tendon repair in 2 patients with a total PDD and ACD value greater than 40 mm, and tendon transfer was performed in 8 patients with the value less than 40 mm. The TAM value, q-DASH score, pinch power, and grip strength were improved in all patients. In both the tendon reconstructions, intraoperative TAM was significantly increased compared with preoperative TAM but significantly decreased at final follow-up. No significant differences were identified in final follow-up TAM and the q-DASH scores between tendon transfer and tendon grafting. CONCLUSIONS: The great advantage of WALANT surgery is that surgeons can evaluate the ruptured musculotendinous unit and measure TAM during the surgery. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic I.