The Double Blow Phenomenon: Back-To-Back C5 Palsy in Compressive Cervical Myelopathy Surgery: A Case Series.

INTRODUCTION: Post-operative C5 palsy remains an unpredictable neurological complication following posterior cervical decompression for cervical compressive myelopathy. This study aimed to analyze its incidence, clinical characteristics, management, and neurological recovery. MATERIALS AND METHODS: This retrospective case series included 9 patients (4.5%) who developed post-operative C5 palsy among 199 posterior cervical decompression procedures performed between January 2023 and January 2026. Demographic, radiological, operative, and neurological data were reviewed. All patients underwent posterior cervical decompression with instrumented stabilization under continuous intraoperative neuromonitoring using motor evoked potentials and somatosensory evoked potentials (SSEPs). Neurological recovery was assessed using serial Medical Research Council muscle strength grading. RESULTS: The mean age was 56.0 ± 12.4 years, with 7 males (77.8%). Severe multilevel cervical stenosis involving predominantly the C3-C7 levels was present in most patients. Stable intraoperative MEP and SSEP signals were observed in all cases. Right-sided C5 palsy occurred in 5 patients (55.6%), and neurological recovery was achieved in 8 patients (88.9%) with conservative management, with a mean recovery duration of 6.2 ± 2.1 weeks. One patient with severe multilevel stenosis and reduced pre-operative cervical lordosis demonstrated persistent neurological deficit at 6 months. CONCLUSION: Post-operative C5 palsy is a delayed neurological complication that usually responds well to conservative treatment. Early recognition and structured rehabilitation remain key to optimizing neurological recovery.