Abstract: Objective To provide a minimally invasive surgical treatment using mobile microendoscopy (mobile MED) for limited cervical spine canal stenosis. Methods Eleven patients were collected from February 2015 to February 2016 in Tianjin Hospital, including 6 males and 5 females, aged 51 - 77 years, mean (67.4 ± 7.6) years. Clinical treatment was performed on 11 patients of limited cervical spinal stenosis. The levels of stenosis included C3- 5 in 5 cases, C4- 6 in 4 cases, C5-7 in 2 cases. The working channel of mobile MED (MMED) can be tilted according to the need of operation. The design of surgical methods: the levels of stenosis were located with fluroscopy, through a posterior median 2.5 cm incision, the nachal ligaments was separated and the spinous process was reached. After a little dissection of paraspinal mascle, the working canal was inserted along the spinous process, and the target lamina was exposed. With MMED, the partial laminectomy was performed along the junction groove of lamina and articular process with high-speed burr, and flavum was exposed and resected with ultra-thin Kerisson, and the dural sac was well exposed. Then the working canal was inserted on the contralateral side along the spinous process, and the decompression was performed with the same method. After bilateral direct decompression, the spinous process and posterior ligament complex shift posteriorly with enlargement of spinal canal. The operation time and blood loss were recorded and the efficacy was followed- up. Results There was no serious complications such as neurological injury. The operation time ranged 80-120 min, with an average of (100±18) min. The intraoperative blood loss ranged (50- 120) mL, with an average of (80 ± 20) mL. Postoperative CT showed sufficient decompression and enlargement of the canal with the posterior shift of the spinous process and posterior ligament complex. The patients were followed up for 6-18 months. The alignment of cervical spine was well preserved on X-ray. The ODI decreased from 42.2±16.3 preoperatively to 6.2±4.3. The JOA score improved from 8.2 ± 3.3 preoperatively to 15.1±4.2 at the last follow-up. According to the improvement rate [(JOA-preoperative JOA) / (17-preoperative JOA)], the results were excellent in 5 cases, good in 5 cases, and effective in 1 case. Conclusion The cervical canal enlargement with mobile microendoscopic discectomy technique preserving posterior ligament composite provides a minimally invasive procedure for limited cervical stenosis with adequate decompression.

Key words: cervical vertebrae, spinal stenosis, surgical procedures, minimally invasive, endoscopy, mobile microendoscopic discectomy