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.
Accurate placement of pedicle screws is a key factor of spinal surgery. Investigation of a new real-time intra-operative monitoring method is an important area of clinical application research which makes a contribution to planting pedicle screw accurately. Porcine spines were chosen as experimental objects.The changes of reduced scattering coefficient (μ's) along normal puncture path, medial perforation path and lateral perforation path were measured and studied. A conclusion is drawn that there are two distinct peaks throughout the puncture process, appearing at the junction of cancellous bone and cortical bone, at the beginning and at the end, respectively. The reduced scattering coefficient is proved to be a good monitoring factor which can identify whether the screw is about to reach the critical position of the spine puncture. Moreover, the variation provides an important reference for spinal surgical navigation process.
ObjectiveTo observe vertebral three-dimensional motion characteristics of adjacent segments in patients with symptomatic L4 isthmic spondylolisthesis (IS). MethodsFourteen symptomatic L4 IS patients who underwent surgery treatment (trial group) and 15 asymptomatic volunteers without back pain and other lesions of spine (control group) were recruited. There was no significant difference in gender, age, body mass index, and bone mineral density between the two groups (P>0.05). The three-dimensional reconstruction model of lumbar spine was acquired from the thin slice CT of the lumbar spine of the subjects by combining dual-X-ray fluoroscopy imaging system with spiral CT examination. The model was matched to the double oblique X-ray fluoroscopy images captured by dual-X-ray fluoroscopy imaging system at different active positions of the lumbar spine to reproduce the three-dimensional instantaneous of lumbar spondylolisthesis at different state of motion. The motion and relative displacement of adjacent segments (L3, 4 and L5, S1) of spondylolisthesis were measured quantitatively by establishing a three-dimensional coordinate system at the geometric center of the vertebral body. The results were compared with those of the control group. ResultsWhen L3, 4 in the control group were flexed flexion-extension, left-right twisting, and left-right bending, and when L5, S1 in the control group were flexed left-right twisting and left-right bending, the activity along the main axis of motion (main axis of motion) tended to increase compared with that along the corresponding coupled axis of motion (secondary axis of motion); however, this trend disappeared in the trial group, and the main and secondary movements were disordered. Because of the coronal orientation of the facet joints of L5, S1, the degree of motion along the main axis of motion decreased during flexion and extension, but this trend disappeared in the trial group. Compared with the control group, L3, 4 in the trial group exhibited displacement instability in flexion-extension, left-right twisting, and left-right bending (P<0.05); there was no significant difference in the relative displacement of L5, S1 intervertebral bodies along x, y, and z axes between the trial group and the control group in flexion-extension, left-right twisting, and left-right bending curvature (P>0.05). ConclusionPatients with symptomatic L4 IS have disorders of primary and secondary movement patterns in adjacent segments, while IS showed significantly displacement instability in L3, 4 and significantly decreased motion in L5, S1.
Objective To design the surgical strategy of percutaneous full-endoscopic bilateral decompression via unilateral posterior approach for bilateral lumbar spinal stenosis (LSS) and to evaluate the effectiveness. Methods The percutaneous full-endoscopic bilateral decompression via unilateral posterior approach for bilateral LSS was designed according to the pathological features of LSS. The technique was used to treat 42 patients with LSS between January 2016 and January 2018. There were 18 males and 24 females with an average age of 61.7 years (range, 46-81 years). The duration of symptoms was 1-20 years, with an average of 9.7 years. The surgical segment at L4, 5 were 27 cases, at L5, S1 were 15 cases. The operation time and perioperative complications were recorded. Lumbar X-ray, CT, and MRI examinations were performed at 1 week, 3 months, and 1 year after operation. Visual analogue scale (VAS) score was used to evaluate the low back pain and leg pain, Oswestry disability index (ODI) was used to evaluate the lumbar function, and single continuous walking distance (SCWD) was used to evaluate lower extremity nerve function. The clinical efficacy was evaluated by MacNab criteria at 1 year after operation. Results All patients underwent surgery successfully. The operation time was 68-141 minutes with an average of 98.2 minutes. All 42 patients were followed up 12-24 months with an average of 18.8 months. There were 2 cases of dural tears during operation, and 1 case of transient dysfunction of the lower limbs of the decompression channel after operation. All of them were cured after corresponding treatment. No serious complications such as death, major bleeding, or irreversible nerve injury occurred during follow-up. No segmental instability was found according to postoperative lumbar hyperextension and flexion X-ray films, and postoperative CT and MRI imaging showed that the stenotic lumbar spinal canal was significantly enlarged, and the compression of the nerve root was sufficient. The VAS score of low back pain and leg pain, ODI score, and SCWD at each time point after operation were significantly improved when compared with those before operation (P<0.05); the indexes were significantly improved over time after operation, and the differences were significantly (P<0.05). The clinical efficacy was evaluated by MacNab standard at 1 year after operation, and the results were excellent in 18 cases, good in 20 cases, fair in 3 cases, and poor in 1 case. The excellent and good rate was 90.5%. Conclusion The percutaneous full-endoscopic bilateral decompression via unilateral posterior approach for LSS is a safe and effective procedure. A well-designed surgical strategy and mastery of its technical points are important guarantees for successful operation and satisfactory results.