To investigate the effectiveness and safety of microendoscopic decompression via unilateral approach for lumbar spinal stenosis. Methods Between May 2006 and June 2009, 79 patients with lumbar stenosis were treated and divided into 2 groups: posterior lamina fenestration decompression (group A, n=37), endoscopic decompression via unilateral approach (group B, n=42). There was no significant difference in age, sex, segment level, and disease duration between 2 groups (P gt; 0.05). The cl inical outcomes were assessed by using the visual analogue scale (VAS) score and Oswestry Disabil ity Index (ODI). The operation time, blood loss, compl ications were compared between 2 groups. Results Operations were successfully performed in all cases. The operation time, blood loss, and drainage volume were (75.0 ± 25.7) minutes, (140.3 ± 54.8) mL, and (46.5 ± 19.7) mL in group A, were (50.4 ± 18.2) minutes, (80.2 ± 35.7) mL, and (12.7 ± 5.3) mL in group B; there were significant differences between 2 groups (P lt; 0.05). All the wounds healed by first intention. All patients were followed up 12-39 months (mean, 16 months). In group A, 1 patient suffered from intervertebral space infection after operation and recovered after conservative treatment; 4 patients had lumbar instabil ity after operation and recovered after lumbar interbody fusion combined with spine system internal fixation. In group B, 2 patients suffered from spinal dural rupture during operation and recovered after corresponding treatment, and no lumbar instabil ity was found. There was no significant difference in VAS score and ODI between 2 groups at preoperation (P gt; 0.05). Both VAS score and ODI were significantly improved at early stage after operation and last follow-up when compared with preoperation in each group (P lt; 0.05). Comparing with group A, there was significant improvement in VAS score at 24 hours postoperatively and in ODI at 1 month postoperatively in group B (P lt; 0.05), but no significant difference was observed at last follow-up (P gt; 0.05). According to cl inical evaluation of ODI mprovement rate, the excellent and good rate was 89.2% in group A and 92.9% in group B, showing no significant difference (χ2=0.896, P=0.827). Conclusion Comparing with posterior decompression surgery, microendoscopic decompression via unilateral approach is one of effective method to treat lumbar stenosis, with less trauma of fenestration yield and good early outcomes.
Objective To analyze the medium and long-term effectiveness of microendoscope-assisted minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) for lumbar degenerative diseases in comparison with conventional tubular retractor-assisted MIS-TLIF. Methods Between November 2008 and March 2013, 53 patients with single segment lumbar degenerative diseases were enrolled. According to the different working channel performed, 28 patients were treated by microendoscope-assisted MIS-TLIF (observation group), while the remaining cases received conventional tubular retractor-assisted MIS-TLIF via Wiltse approach (control group). Preoperative baseline data, including age, gender, body mass index, disease etiology, operated level, the ration for requiring bilateral canal decompression, and preoperative visual analogue scale (VAS) socre of low back pain and leg pain, Japanese Orthopedic Association (JOA) score, Oswestry disability index (ODI) score, showed no significant difference between the two groups (P>0.05). The operation time, intraoperative blood loss, intraoperative fluoroscopy time, postoperative analgesic drug dose, postoperation in-bed time, and perioperative complication incidence were recorded respectively and compared between the two groups. Radiographic evaluation of interbody fusion was performed based on Bridwell grading system at 2 years after operation. VAS scores of low back pain and leg pain, JOA score, and ODI score were assessed before operation, at 2 years after operation, and at last follow-up respectively. Surgical outcome satisfaction was assessed by modified MacNab criteria at last follow-up. Results When compared with those in control group, both intraoperative blood loss and postoperative analgesic drug dose were significantly decreased in observation group (P<0.05); similarly, the operation time and intraoperative fluoroscopy time were also significantly increased in observation group (P<0.05). There was no significant difference of postoperative in-bed time between the two groups (t=–0.812, P=0.420). Both groups were followed up 6-10.3 years, with an average of 7.9 years. Regarding perioperative complication, its incidence was 14.3% and 20.0% in observation group and control group, respectively, showing no significant difference between both groups (χ2=0.306, P=0.580). Specifically, there were intraspinal hematoma formation in 1 case, incision infection in 1 case, urinary infection in 1 case, transient delirium in 1 case in observation group. By contrast, there were dural tear and cerebrospinal fluid leakage in 1 case, urinary infection in 1 case, pneumonia in 1 case, transient delirium in 2 cases in control group. Bridwell criterion was used to judge the intervertebral fusion at 2 years after operation, the fusion rates of observation group and control group were 92.9% and 92.0%, respectively, showing no significant difference (χ2=0.162, P=0.687). At both 2-year postoperatively and last follow-up, the VAS scores of low back pain and leg pain, JOA score, and ODI score were significantly improved when compared with those before operation (P<0.01), whereas no significant difference between the two groups at either time point was found (P>0.05). At last follow-up, the results of patients’ satisfaction with surgery evaluated by modified MacNab criteria, and the excellent and good rates of the observation group and the control group were 96.4% and 92.0%, respectively, showing no significant difference (χ2=0.485, P=0.486). Conclusion The medium and long-term effectiveness of microendoscope-assisted MIS-TLIF are similar to those of conventional tubular retractor-assisted MIS-TLIF for lumbar degenerative diseases. The former operation has the additional advantages in terms of more clear surgical site visually, less intraoperative blood loss, and reduced postoperative analgesic dose, all of which seem more feasible to clinical teaching.