Active shoulder external rotation recovery in upper brachial plexus birth injury following nerve surgery: is spinal accessory nerve–suprascapular nerve transfer superior to C5–suprascapular nerve grafting?

XIN-SSN transfer results in superior active ER compared to nerve grafting. Future studies should investigate whether the long-term impact of trapezius muscle loss is acceptable, to determine whether nerve transfer should be prioritized over grafting in the presence of a graftable C5 root.