OBJECTIVE The effectiveness of contralateral C-7 (CC7) transfer is controversial, yet this procedure has been performed around the world to treat brachial plexus injuries. The authors performed a systematic review to study whether Asian countries reported better outcomes after CC7 transfer compared with "other" countries. METHODS A systematic literature search using PubMed, EMBASE, and 3 Chinese databases was completed. Patient outcomes of CC7 transfer to the median and musculocutaneous (MC) nerves were collected and categorized into 2 groups: Asia and "other" countries. China was included as a subcategory of Asia because investigators in China published the majority of the collected studies. To compare outcomes among studies, we created a normalized Medical Research Council (MRC) scale. RESULTS For median nerve outcomes, Asia reported that 41% of patients achieved an MRC grade of ≥ M3 of wrist flexion compared with 62% in "other" countries. For finger flexion, Asia found that 41% of patients reached an MRC grade of ≥ M3 compared with 38% in "other" countries. Asia reported that 60% of patients achieved ≥ S3 sensory recovery, compared with 32% in "other" countries. For MC nerve outcomes, 75% of patients from both Asia and "other" countries reached M4 and M3 in elbow flexion. CONCLUSIONS Current data did not demonstrate that studies from Asian countries reported better outcomes of CC7 transfer to the median and MC nerves. Future studies should focus on comparing outcomes of different surgical strategies for CC7 transfer.
Keywords: BMI = body mass index; BPAI = brachial plexus avulsion injury; BPI = brachial plexus injury; CC7 = contralateral C-7; MC = musculocutaneous; MRC = Medical Research Council; contralateral C-7 transfer; median nerve; musculocutaneous nerve; peripheral nerve; traumatic brachial plexus palsy.