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1. Severe Parsonage-Turner syndrome (PTS) shows a high rate (86%) of spontaneous motor-unit reinnervation despite absent activation on EMG, contrasting with lower recovery in traumatic brachial plexopathy (TBP) requiring surgery.
2. Functional recovery measured by DASH scores improved substantially in PTS (mean improvement of 44.7 points) compared to modest gains in surgically treated TBP (mean improvement of 9.8 points).
3. High-grade focal nerve constrictions identified by MRI are uncommon in PTS (4%), limiting the role for surgical intervention in this immune-mediated plexopathy.
4. In TBP, earlier nerve reconstruction (<3 months) yields higher reinnervation rates, emphasizing the benefit of timely surgical management.
