Surgical Outcomes of Cervical Disc Herniation Causing Deltoid Palsy: Multicenter Study

In general, deltoid palsy develops in patients with cervical disc herniation (CDH) at the level of C4–5, resulting in compression of the C5 nerve root. Because of duplicate nerve innervation, however, deltoid palsy can also develop when CDH is at the levels of C3–4 and C5–6. To date, little has been known about the surgical outcomes of CDH causing deltoid palsy. We report on by far the largest series of CDH causing deltoid palsy focusing on surgical outcomes in the literature.Patients and Methods A total of 61 patients with CDH causing deltoid palsy (less than grade 3) were identified among 13 surgeons and included in this study. Average age of the patients was 51.4 years (range, 25–69 years), with 49 males and 12 females. Overall, 35 patients were soft disc and 26 patients were hard disc. Overall, 32 patients had single-level CDH (22 C4–5, 9 C5–6 and 1 C3–4), 22 had two-level (19 C4–5-6, 2 C3–4-5 and 1 C5–6-7), 4 had three-level (4 C4–5-6–7), 3 had four-level (3 C3–4-5–6-7). All the patients underwent surgery for deltoid palsy and arm pain not responding to conservative treatment: 57 ACDF, 2 ADR, and 2 foraminotomy and discectomy. Average follow-up was 20.7 months (range, 6–83 months). The severity of deltoid palsy was classified into five grades according to manual motor power test, and the severity of radiculopathy was recorded on a visual analog scale (VAS) of arm pain (0–10 points). The degree of improvement in both the severity of deltoid palsy and arm pain following surgery was evaluated. Patients with accompanying myelopathy, shoulder diseases, or peripheral neuropathy were excluded from the study.Results Average duration of deltoid palsy was 11.9 weeks (range, 1–156 weeks). Both deltoid palsy and radiculopathy improved significantly with surgery (2.4 vs. 4.5 grades, p < 0.001) and (6.4 vs. 2.1 points, p < 0.001), respectively. Of 61 patients, 36 (59%) patients achieved full recovery of deltoid palsy with an average time of 8.4 weeks (range, 1–54 weeks). Longer duration of deltoid palsy negatively affected the degree of improvement of deltoid palsy after surgery (correlation coefficient −0.351; p < 0.01). Severity of preoperative deltoid palsy, type of disc (soft disc or hard disc), and gender did not affect the degree of improvement of deltoid palsy after surgery.Conclusion This study demonstrates that surgical decompression significantly improves the degree of deltoid palsy and radiculopathy because of the CDH irrespective of the type of disc. The longer the duration of deltoid palsy preoperatively, the lower the degree of improvement of deltoid palsy postoperatively. Thus, early surgical decompression is recommended for improvement of deltoid palsy in patients with CDH.