Objective To investigate the role of BMSCg on enhancing the implant survival and bacheal epithelium regeneration. Methods After transplanted with cryopreserved 2 weeks and 6 weeks allocraft, PHK-26 labeled 3-5 passage BMSCs were injected into the recipient rats via tail vein. Rats in the control groups were injected with the same amount of PBS.We observed the histology of the transplanted trachea including epithelium growth and regeneration, and the PKH-26 fluorescence levels at the para-anastomotic trachea to evaluate the role of BMSC transplantation on the epithelium regeneration. Results Rats from BMSCs injection group survived a long period. Histological observation showed that the tracheal lumen was covered by psudo-striated ciliated columnar epithelium. The cartilage structure was intact. There are no signs of denaturation and necrosis. In the PBS injection group, epithelium regeneration is better in PBS-6-week group than PBS-2-week group. The longest survival time in PBS-6-week group was 32 days, whereas it was 10 days in PBS-2-week group. In BMSCs injection group, rats in BMSC-6-week groups survived longer than 8-week group(12 rats were terminated at 1 week, 4 weeks and 8weeks as planned). There was one rat who survived and were terminated at the designated 8 weeks time point (there were 8regenerated epithelium was similar in the two BMSC transplanted groups. PKH-26 labeled BMSCs migrated to the implant site and showed red fluorescence, with most red fluorescence shown at the anastomotic part. Conclusion BMSCs can migrate to the impaired tissue to repair it. BMSCs may exert their reparation function via enhancing epithelium regeneration.

Objective To explore the clinical efficacy of V-shape bichannel spinal endoscopy(VBE)in the treatment of degenerative lumbar spondylolisthesis(DLS)in elderly patients.Methods A total of 110 patients with DLS admitted to Wu'an First People's Hospital from June 2017 to April 2023 were selected as the research subjects.According to the surgical plan,these patients were divided into the minimally invasive transforaminal lumbar interbody fusion(MIS-TLIF)group and the VBE group,with 55 patients in each group.The general indicators of patients in the two groups during and after surgery,inclu-ding the length of the surgical incision,operation time,number of X-ray fluoroscopy,intraoperative blood loss,hospitalization time,and bed rest time were recorded.Before surgery and three,six months after surgery,the visual analogue scale(VAS)was used to assess the degree of pain in the back and legs,and the Oswestry disability index(ODI)was used to assess the lumbar function of the patients.The Brantigan score was used to assess bone fusion in patients at three months after surgery.X-ray films were taken before surgery and three,six months after surgery to measure the spondylolisthesis degree,intervertebral height,spondylolisthesis angle,and sagittal Cobb angle at the surgical segment.The Japanese Orthopaedic Association(JOA)score was used to assess the excellent and good rate of lumbar function in patients at six months after surgery.The incidence of postoperative complications of patients in both groups was recorded.Results The length of surgical incision,operation time,bed rest time,and hospitalization time of patients in the VBE group were significantly shorter than those in the MIS-TLIF group,and the intraoperative blood loss and X-ray fluoroscopy times were significantly less than those in the MIS-TLIF group(P＜0.05).There was no significant difference in VAS scores for low back pain and leg pain and ODI index between the two groups before surgery(P＞0.05).The VAS scores for low back pain and leg pain and the ODI index of patients in both groups at three and six months after surgery were significantly lower than those before surgery(P＜0.05).There was no significant difference in the VAS scores for low back pain and leg pain and ODI index between the VBE group and the MIS-TLIF group at three and six months after surgery(P＞0.05).There was no significant difference in the distribution of Brantigan scores of patients between the VBE group and the MIS-TLIF group(P＞0.05).There was no significant difference in the sagittal Cobb angle,intervertebral height,spondylolisthesis angle,and spondylolisthesis degree at the surgical segment of patients between the two groups before surgery(P＞0.05).The sagittal Cobb angle and intervertebral height at the surgical segment of patients in both groups at three and six months after surgery were significantly higher than those before surgery(P＜0.05),while the spondylolisthesis angle and spondylolisthesis degree were significantly lower than those before surgery(P＜0.05).There was no significant difference in the sagittal Cobb angle,intervertebral height,spondylolisthesis angle and spondylolisthesis degree at the surgical segment of patients between the two groups at three and six months after surgery(P＞0.05).At six months after surgery,the excellent and good rate of lumbar function in the VBE group and the MIS-TLIF group was 100.00％(55/55)and 98.18％(54/55),respectively.There was no significant difference in the excellent and good rate of lumbar function between the two groups(P＞0.05).No complications occurred in patients in the VBE group after surgery,while one patient in the MIS-TLIF group experienced incision exudation and delayed healing.Conclusion VBE treatment for degenerative lumbar spondylolisthesis in elderly patients shows similar efficacy with MIS-TLIF in terms of lumbar morphology,functional recovery,and safety.However,VBE can reduce tissue damage,enable earlier ambulation,and thereby accelerate the early postoperative recovery process.