De novo C5 palsy in the absence of prior surgery: a retrospective study of surgical management and outcomes in the United States

STUDY DESIGN: Retrospective cohort study. PURPOSE: This study aimed to document the presentation, treatment, and clinical outcomes of surgically managed de novo C5 palsies. OVERVIEW OF LITERATURE: De novo C5 motor palsy-occurring without prior cervical spine intervention or trauma-presents with a unique constellation of symptoms. Unlike typical multilevel cervical radiculopathy, patients with de novo C5 palsy primarily experience motor deficits, most notably affecting the deltoid and biceps. The etiology of their symptoms may be attributed to intrinsic spinal pathologies, including foraminal stenosis and spinal cord compression. METHODS: A total of 31 C5 motor palsies in 26 patients were included in this case series. Patients underwent 16 anterior cervical discectomy and fusions, six laminoplasties, and four laminectomies with fusion procedures. Visual Analog Scale (VAS) pain scores, Neck Disability Index (NDI), and strength scores were recorded during pre- and postoperative follow-up visits. Statistical analysis was conducted using Fisher's exact test and a paired t-test with analysis of variance. RESULTS: The mean preoperative motor strength grades for the deltoid and biceps were 2.1 and 3.2, respectively. At final follow-up, mean deltoid and bicep motor grades had significantly improved compared to preoperative values (p <0.0001, p <0.0001, respectively). Significant improvements were also observed in NDI scores (39.3 to 26.7, p <0.05) and VAS pain scores (4.42 to 2, p <0.05) at final follow-up. CONCLUSIONS: This study is the first to report outcomes of surgical management for spontaneous, de novo C5 motor palsies. Following surgical intervention, patients experienced favorable recovery of deltoid and bicep motor strength. Both anterior and posterior approaches resulted in successful motor recovery when appropriately selected based on preoperative imaging and surgical planning.