Posterior endoscopic cervical foramiotomy and discectomy: clinical and radiological computer tomography evaluation on the bony effect of decompression with 2 years follow-up

Abstract

Abstract Purpose Cervical radiculopathy is a common disabling cervical spine condition. Open anterior and posterior approaches are the conventional surgical treatment approaches with good clinical outcomes. However, the soft tissue damage in these procedures can lead to increase perioperative morbidity. Endoscopic spine surgery provides more soft tissue preservation than conventional approaches. We investigate the radiological and clinical outcomes of posterior endoscopic cervical foraminotomy and discectomy. Methods A prospective clinical and radiological study with retrospective evaluation were done for 25 patients with 29 levels of cervical radiculopathy who underwent posterior endoscopic cervical discectomy from November 2016 to December 2018. Clinical outcomes of Visual Analogue Scale, Neck Disability Index and MacNab’s score were evaluated at pre-operative, post-operative 1 week, 3 months and final follow-up. Preoperative and post-operative final follow-up flexion and extension roentgenogram were evaluated for cervical stability assessment. Pre-operative and post-operative computer tomography cervical spine evaluation of foraminal length in ventro-dorsal, cephalad-caudal dimensions, sagittal foraminal area and using 3D CT reconstruction coronal decompression area were done. Results Twenty-nine levels of cervical radiculopathy underwent posterior endoscopic cervical decompression. The mean follow-up was 29.6 months, and the most common levels affected were C5/6 and C6/7. There was a complication rate of 12% with 2 cases of neurapraxia and one case of recurrent of prolapsed disc. There was no revision surgery in our series. There was significant clinical improvement in Visual Analogue Scale and Neck Disability Index. Prospective comparative study between preoperative and final follow-up mean improvement in VAS score was 5.08 ± 1.75, and NDI was 45.1 ± 13.3. Ninety-two percent of the patients achieved good and excellent results as per MacNab’s criteria. Retrospective evaluation of the radiological data showed significant increments of foraminal dimensions: (1) sagittal area increased 21.4 ± 11.2 mm2, (2) CT Cranio Caudal length increased 1.21 ± 1.30 mm and (3) CT ventro-dorsal length increased 2.09 ± 1.35 mm and (4) 3D CT scan reconstruction coronal decompression area increased 536 ± 176 mm2, p < 0.05. Conclusion Uniportal posterior endoscopic cervical foraminotomy and discectomy are safe, efficient and precise choreographed set of technique in the treatment of cervical radiculopathy. It significantly improved clinical outcomes and achieved the objective of increasing in the cervical foramen size in our cohort of patients.