Nerve Transfer or Musculotendinous Transfer for Elbow Flexion: What Is the Evidence? A Systematic Review

Both nerve transfers and tendon transfers can restore elbow flexion after upper extremity nerve injury. Our objective was to determine whether there is any difference in outcomes in patients undergoing a nerve transfer versus tendon transfer to restore elbow flexion between 6 and 12 months following injury. Two independent reviewers reviewed electronic databases to identify studies that reported patients undergoing a nerve or tendon transfer within 6−12 months after injury and evaluated any of the following outcomes: range of motion, strength, quality of life, cost, or complications. Methodological quality of the studies was assessed using the MINORS scale. Seven of 417 retrieved articles met the inclusion criteria and were included in the final analysis. The interrater agreement was high (κ = 0.88). The mean range of motion was 21.7 degrees for 3 nerve transfer patients compared with 122.5 degrees for 2 tendon transfer patients. Of 5 nerve transfer patients, mean postoperative strength was 2.4 kg compared with 3.5 kg for 2 tendon transfer patients. There is consistent low-quality evidence to support the effectiveness of tendon transfer with respect to range of motion and strength in patients with elbow injury. A meta-analysis was not feasible because of the heterogeneity in the study designs and outcomes. There is a strong need for future longitudinal randomized trials to make definitive conclusions regarding the effectiveness of tendon transfers over nerve transfers.