Spinal cord injury is a difficult medical problem and need to be solved urgently.Application of tissue engineering to repair spinal cord injury has gradually become a hot spot.It is important to prevent the development of scar tissue while inducing cells' regeneration by using scaffold.Nanotechnology has improved the performance of scaffold because of its superiority.Nanoscaffold has obvious advantages compared with the traditional scaffolds.New scaffold materials can be obtained by nanotechnology.Nanoscaffold can also serve as a good drug carrier,and it may have beneficial effects on biological behaviors of seed cells on its surface,such as differentiation,proliferation and migration,which may promote tissue regeneration and functional recovery and get good results in repairment of spinal cord injury.This article summarized the research progress in recent years in nano spinal cord engineering scaffolds in order to provide a reference for research in related fields.

Objective To investigate the clinical value of spinal nonfusion interspinous Coflex system for the degenerative lumbar spinal stenosis.Methods From March 2008 to August 2009,26 patients with degenerative lumbar spinal stenosis were treated by decompression with posterior spinous process and interspinous implant Coflex folder method,including 11 males and 15 females,with the mean age of 65.4years(range,45-78 years).L3,4 segment in 7 cases,L4,5 segment in 13 cases,concomitant L3,4,L4,5 segment stenosis in 6 cases.Patients were scanned by MRI and CT confirmed L3,4 and(or)L4,5 segments of the ligamentum flavum thickening,proliferation of small-joint bone,merger disc herniation causing central tube and lateral fossae stricture,nerve root or coccygeal plexus compression.Lumbar anteroposterior,lateral and flexion-extension X-ray films preoperatively,and at follow-up were used to measure the following parameters by eFilm and CAD software:the anterior and posterior disc space height,the range of motion at surgical level,and the segment of the spinal canal area of responsibility.Postoperative standard Japanese Orthopaedic Association(JOA)score for preoperative and postoperative scores.Results Patients were followed up 12-24months.The pain relieved in all patients.The JOA scores improved from(15.46 ±4.30)preoperatively to (24.50±1.58)postoperatively,the vertebral canal area of the affected segment was(218.4±16.2)mm2 before the operation,(264.6±9.9)mm2 after the operation.Single segment anterior disc space height did not change significantly,the difference was not statistically significant.The disc space posterior height increased compared with the preoperative height,and gradually decreased with time.No patients suffered Coflex loosening,fracture and emerge.Conclusion The treatment of lumbar spinal stenosis with Coflex system has satisfactory effect in minimal invasiveness and high security,which provides a safe and effective therapy for degenerative lumbar spinal stenosis.

Objective:To compare the efficacy and safety of cap-assisted endoscopic sclerotherapy (CAES) and procedure for prolapse and hemorrhoids (PPH) for internal hemorrhoids.Methods:This study was a prospective double-blind controlled clinical one. A total of 80 patients with internal hemorrhoids who visited Baoding No.1 Central Hospital from March 2018 to March 2020 and met the inclusion and did not meet exclusion criteria, were randomly divided into CAES group ( n=40) and PPH group ( n=40) by random number table method, and received corresponding treatment respectively. The perioperative indices of the two groups were compared, including intraoperative blood loss, operation time, visual analogue scale (VAS) score at 24 and 48 hours after operation, length of hospital stay, treatment costs, time to return to normal life, and curative rates. The complications within 3 months after operation and the 1-year recurrence after operation were also compared between the two groups. Results:The operation was successfully completed in all patients. The intraoperative blood loss (0.54±0.15 mL VS 7.32±2.17 mL) and treatment cost (6 249.53±435.67 yuan VS 7 832.96±526.74 yuan) in CAES group were significantly lower than those in PPH group ( t=19.714, P<0.05; t=14.650, P<0.05). The length of hospital stay (3.53±0.94 d VS 5.18±1.36 d) and time to return to normal life (5.26±1.28 d VS 7.17±2.09 d) in CAES group were significantly lower than those in PPH group ( t=6.312, P<0.05; t=4.929, P<0.05). There was no significant difference in operation time between the two groups ( t=0.977, P>0.05). The VAS scores at 24 h (2.64±0.70 points VS 3.59±0.93 points) and 48 h (1.28±0.31 points VS 2.16±0.57 points) after operation in CAES group were significantly lower than those in PPH group ( t=5.162, P<0.05; t=8.578, P<0.05). There was no significant difference in the curative rate [90.0% (36/40) VS 97.5% (39/40)] between CAES group and PPH group ( χ2=0.853, P=0.356). During the follow-up period within 3 months after the operation, the incidence of urinary retention [0.0% (0/40) VS 15.0% (6/40)] and pain [2.5% (1/40) VS 22.5% (9/40)] in CAES group was significantly lower than those in PPH group ( χ2=4.504, P<0.05; χ2=7.314, P<0.05). No other complications occurred in the 80 patients. After 1 year of follow-up, the recurrence rate of CAES group was 7.5% (3/40), which was not statistically different from that in PPH group [5.0% (2/40), χ2=0.180, P>0.05]. Conclusion:As a new minimally invasive technique for the treatment of internal hemorrhoids, CAES has similar curative rate and 1-year recurrence rate to PPH. Compared with PPH, CAES shows the advantages of less trauma, less pain, faster recovery and lower cost.