Shoulder and Elbow Recovery at 2 and 11 Years Following Brachial Plexus Reconstruction

To report short-term and long-term outcomes on a single patient cohort observed longitudinally after nerve reconstruction for adult brachial plexus injury.

Eleven male patients who underwent plexus reconstruction by the same surgeon at 2 institutions presented for clinical examination 7.5 or more years after surgery (average, 11.4 years; range, 7.5-22 years). Average age at the time of operation was 35 years (range, 17-73 years). Mean delay until surgery was 5 months (range, 2-11 months). Two patients had C5 paralysis, 2 had C5-C6 paralysis, 2 had C5-C7 paralysis, and 5 had complete 5-level injuries. Outcome parameters included active range of motion (ROM) in degrees, a modified British Medical Research Council (mBMRC) scale for muscle strength, and electromyographic motor unit configuration and recruitment pattern. Differences in ROM and mBMRC between 2-year and long-term follow-up were assessed with paired-sample t tests using an alpha value of .05.

Average shoulder abduction and mBMRC at final follow-up were both significantly improved compared with the 2-year follow-up results (P < .05). Average elbow flexion and mBMRC increased significantly between 2 years and final follow-up (P < .05). Electromyographic results for 6 patients at final follow-up showed improved motor unit configuration in 10 of 15 muscles and improved recruitment in 3 of 15 muscles compared with 2-year electromyographic results.

Patients continued to gain ROM and strength in the shoulder and elbow well after 2 to 3 years after surgery, contrary to previous reports. Although the precise mechanism is unknown, we speculate that a number of factors may be involved, including terminal collateral sprouting, maturation of motor units, improvements in motor unit recruitment, additional muscle fiber hypertrophy, or an as-yet undescribed mechanism. We recommend that patients be encouraged to continue strengthening exercises well after the initial recovery period and that more comparative long-term data be collected to expand on these observations.