[Treatment of senile lumbar spinal stenosis by unilateral approach and bilateral decompression with large channel endoscopy].

Objective: To evaluate clinical effect of unilateral approach and bilateral decompression via large channel endoscopic system for the treatment of lumbar spinal stenosis.

Methods: The clinical data of 32 patients with lumbar spinal tenosis treated by unilateral approach and bilateral decompression via large channel endoscopy from February 2018 to February 2019 were retrospectively analyzed. There were 18 males and 14 females, aged 65 to 84 years old with an average of (70.6± 8.4) years. The course of disease was from 1 to 12 years. All 32 cases were accompanied by numbness or pain in the lower limbs, of which 28 cases were accompanied by intermittent claudication. Narrow segments were L of 2 cases, L of 19 cases, LS of 13 cases, including double segments of 2 cases. Preoperative imaging showed 3 cases of central canal stenosis, 21 cases of bilateral lateral recess stenosis and 8 cases of mixed stenosis. Operation time and complications were recorded. X-ray, CT and MRI were analyzed at 3 days, 3 months and 1 year after operation. Visual analogue scale(VAS), Oswestry Disability Index (ODI), single continuous walking distance(SCWD) were observed before and after operation. Modified Macnab standard were used to evaluate the clinical effect at 1 year after operation.

Results: All the patients were followed up for 12-24 (17.68±2.43) months and all operations were successfully completed with the operation time of 70-160(85.64±11.94) min. Spinal dural tear occurred in 1 case during the operation, and sensory disturbance in the other side of lower limb in a short period of time occurred in 2 cases, all improved after corresponding treatment. Postoperative imaging showed that the spinal canal was significantly enlarged and the nerve root was fully released. Before operation and 3 days, 3 months, 1 year after operation, VAS scores of low back pain were 4.62 ±1.41, 2.73 ±1.35, 1.21 ±1.17, 1.11 ±0.34, respectively;VAS scores of leg pain were 6.83 ± 1.71, 3.10±1.50, 1.08±0.19, 0.89±0.24, respectively. VAS scores of low back pain and leg pain each time point after operation were obvious improved (<0.05); there was significant difference between 3 months and 3 days after operation(<0.05), and there was no significant difference between 3 months and 1 year after operation (>0.05). Before operation and 3 days, 3 months, 1 year after operation, ODI scores were 38.40 ±6.48, 18.42 ±2.40, 5.48 ±0.77, 3.05 ±0.28, respectively; SCWD was (47.48±5.32) m, (52.89±11.23) m, (245.43±18.94) m, (468.97±55.87) m, respectively. The differences in ODI score and SCWD postoperative time points were statistically significant compared with those before operation (<0.05). The difference between 3 months and 3 days after operation was statistically significant (<0.05). The difference between 1 year and 3 months after operation was statistically significant (<0.05). According to Macnab standard to evaluate clinical effect at 1 year after operation, 15 cases got excellent results, 14 good, 3 fair.

Conclusion: It is a safe and effective way to treat lumbar spinal stenosis with unilateral approach and bilateral decompression via large channel endoscopic system. It has the advantages of sufficient decompression, less trauma, fast recovery, high safety and low incidence of postoperative complications. It can minimize the damage to the stable structure of the lumbar spine and is an ideal minimally invasive operation for the treatment of lumbar spinal stenosis.