Objective To investigate the technique of reduction by posterior approach for severe spondylolisthesis, and to discuss the method to prevent nerve stretch injury. Methods Between July 2007 and April 2011, 17 patients with severe spondylolisthesis underwent reduction, fixation, and fusion by posterior approach. There were 2 males and 15 females with a median age of 15 years (range, 8-67 years) and a median disease duration of 18 months (range, 5 months-16 years and 4 months). The level of spondylolisthesis was at L4 in 1 case and L5 in 16 cases; the spondylolisthesis was at degree III in 12 cases and degree IV in 5 cases according to Meyerding classification. There were 16 cases of developmental spondylolisthesis (high- dysplastic and low-dysplasia spondylolisthesis in 9 and 7 cases, respectively) and 1 case of traumatic spondylolisthesis; 16 cases of developmental spondylolisthesis at L5 level included 6 cases of type 4, 9 case of type 5, and 1 case of type 6 according to Spinal Deformity Study Group (SDSG) classification. All cases underwent posterior spinal decompression, Schanz screw fixation for the slipped vertebrae, the intervertebral and posterolateral fusion and reduction of the slipped vertebrae, and correction of the lumbosacral kyphosis. The reductive degree of slipped vertebrae was modulated according to the strain of exiting spinal root. The slip degree should be reduced within Meyerding degree II. The anteroposterior and lateral radiographs of whole spine were taken in a standardized standing position to observe the correction of displacement severity and lumbosacral angle. The nerve function and pain score of lower extremity were evaluated by neurological Frankel grade and visual analogue scale (VAS). Bony fusion was assessed by followed-up CT three-dimentional reconstruction. Results Exiting nerve root paralysis occurred in 1 case after operation, and released at 4 weeks after operation; no aggravation of nerve damage was observed in the other patients. The incisions primarily healed. All the patients were followed up 12-48 months (mean, 25 months). The slip percentage, the lumbosacral angle, and VAS score of lower extremity were improved from 72% ± 10%, (18.2 ± 3.5)°, and 7.0 ± 1.5 at preoperation to 12% ± 6%, ( — 7.3 ± 2.9)°, and 1.5 ± 1.3 at 12 months after operation respectively, all showing significant differences (P lt; 0.05). Osteosynthesis was seen at the bone grafting area by CT three-dimentional reconstruction at 12 months after operation. No breakage of screw and rod or reduction loss occurred. Conclusion It can obtain satisfactory clinical result to use spinal canal decompression by posterior approach, the Schanz screw fixation of the slipped vertebrae, the intervertebral and posterolateral fusion for severe spondylolisthesis. The risk of nerve stretch injury can be prevented by choosing the lowest height of intervertebral cage, modulating the reductive degree of slipped vertebrae according to the strain of exiting spinal root, and correcting lumbosacral kyphosis.
Objective To evaluate the mid-term cl inical outcome of instrumented sl ip reduction combined with 360° circumferencial fusion and restoration laminae for symptomatic adult isthmic spondylol isthesis. Methods Between October 2004 and March 2008, 44 patients with symptomatic isthmic spondylol isthesis underwent instrumented sl ip reduction combined with 360° circumferencial fusion and restoration laminae. There were 15 males and 29 females with an average age of38.4 years (range, 28-45 years). The disease duration was 14 months to 7 years (38 months on average). The affected vertebrae was L4-5 in 18 patients and L5, S1 in 26 patients. According to Meyerding’s grade for spondylol isthesis, 28 cases were rated as grade II and 16 as grade III. The visual analogae scale (VAS), Oswestry disabil ity index (ODI), and the short form 36 health survey (SF-36) scores were evaluated before operation and at last follow-up; the radiographical outcome was evaluated by measuring sl i pping percentage, heights of intervertebral space and foramen, and fusion rate. Results All patients were followed up 20-60 months (42 months on average). The VAS, ODI, and SF-36 scores were all significantly improved at last follow-up when compared with those before operation (P lt; 0.05). According to Morelos criteria, the cl inical results were excellent in 32 patients, good in 9, and fair in 3; the excellent and good rate was 93.2%. The preoperative average percentage of sl ip was 47.5%, which was improved to 2.6% 3 days after operation; the total average reduction rate was 97.4%, and it was maintained at last followup. The heights of intervertebral space and foramen were all improved significantly after operation (P lt; 0.05), and there was no significant difference between at 3 days after operation and at last follow-up (P gt; 0.05). X-ray and CT showed bony fusion 1 year after operation in all patients with a fusion rate of 100%. Compl ications included pain at donor site of il iac bone in 4 cases, superficial infection in 2 cases, dural tear in 1 case, and degeneration of adjacent vertebrae in 2 cases; no nerve root injury, pseudoarthrosis, failure of internal fixation, and acquired spinal canal stenosis occurred. Conclusion Instrumented sl ip reduction combined with 360° circumferencial fusion and restoration laminae is a rel iable procedure for adult isthmic spondylol isthesis with satisfactory mid-term results, a high fusion rate and low compl ication rate. The long-term outcomesshould be verified by follow-up in the future.
ObjectiveTo explore the effectiveness of posterior lumbar interbody fusion in the treatment of double-segmental bilateral isthmic lumbar spondylolisthesis. MethodsBetween February 2008 and December 2013, 17 patients with double-segmental bilateral isthmic lumbar spondylolisthesis were treated with posterior lumbar interbody fusion. There were 12 males and 5 females, with an age ranged 48-69 years (mean, 55.4 years). The disease duration ranged from 11 months to 17 years (median, 22 months). According to the Meyerding classification, 30 vertebrea were rated as degree I, 3 as degree Ⅱ, and 1 as degree Ⅲ. L4, 5 was involved in 14 cases and L3, 4 in 3 cases. The preoperative visual analogue scale (VAS) score was 8.6±3.2. ResultsCerebrospinal fluid leakage occurred in 2 cases because of intraoperative dural tear; primary healing of incision was obtained, with no operation related complication in the other patients. The patients were followed up 1-6 years (mean, 3.4 years). At last follow-up, VAS score was decreased significantly to 1.1±0.4, showing significant difference when compared with preoperative score (t=7.652, P=0.008). X-ray films showed that slippage vertebral body obtained different degree of reduction, with a complete reduction rate of 85% (29/34) at 1 week after operation. All patients achieved bony union at 6-12 months (mean, 7.4 months). According to the Lenke classification, 13 cases were rated as grade A and 4 cases as grade B. No internal fixation loosening and fracture were observed during the follow-up. Intervertebral disc height was maintained, no loss of spondylolisthesis reduction was found. ConclusionIt can obtain satisfactory clinical result to use spinal canal decompression by posterior approach, and screw fixation for posterior fusion in treatment of double-segmental bilateral isthmic lumbar spondylolisthesis. The key points to successful operation include accurate insertion of screw, effective decompression, distraction before reduction, rational use of pulling screws, and interbody fusion.
Objective To analyze the effectiveness of combined treatment of lumbar spondylolisthesis with MED, Quadrant, and Sextant-R systems. Methods Between August 2006 and June 2011, 35 patients with lumbar spondylolisthesis were treated, including 11 cases of isthmic spondylolisthesis and 24 cases of degenerative spondylolisthesis. There were 25 males and 10 females, with a mean age of 55 years (range, 33-71 years). The mean disease duration was 37 months (range, 8-75 months). Spondylolisthesis occurred at L4, 5 level in 21 patients and at L5, S1 level in 14 patients. According to Meyerding classification, 35 cases were rated as dergee I. The minimally invasive surgeries were performed by paraspinal muscle approach; Quadrant system was used for decompression and fusion at severe side, MED system for windowing of lamina at mild side, and Sextant-R system for fixation and reduction. Visual analogue scale (VAS) score was used to evaluate pain, Oswestry disability index (ODI) to evaluate clinical outcomes, spondylolishesis ratio and intervertebral height to evaluate spondylolisthesis reduction. Results Lumbar continuous thin layer CT at postoperation showed that no pedicle screw invaded spinal canal and intervertebral fusion device was at good position. Incisions healed by first intention. All patients were followed up 18-38 months (mean, 26 months). All patients got bone fusion and had no internal fixation failure by radiologic examination at 1 year after operation. Low back pain was relieved, lumbar function improved obviously, and satisfactory reduction of spondylolisthesis was obtained. At 2 weeks and 1 year after operation, the VAS score, ODI score, spondylolisthesis ratio, and intervertebral height were significantly improved when compared with preoperative ones (P lt; 0.05). VAS score and ODI score showed significant differences (P lt; 0.05) between at 2 weeks and 1 year after operation. Spondylolisthesis ratio and intervertebral height showed no significant difference (P gt; 0.05) between at 2 weeks and at 1 year after operation. Conclusion Minimally invasive surgical management for lumbar spondylolisthesis via MED, Quadrant, and Sextant-R systems is a safe and effective surgical technique. However, its indications should be well considered.
Objective To investigate the effect of the sagittal alignment of the spine and pelvis after surgical posterior intervertebral fusion combined with pedicle screw fixation for low-grade isthmic lumbar spondylolisthesis, and to assess the effectiveness. Methods Between October 2009 and October 2011, 30 patients with low-grade isthmic spondylolisthesis underwent surgical posterior intervertebral fusion combined with pedicle screw fixation, and the clinical data were retrospectively reviewed. There were 14 males and 16 females with an average age of 56.7 years (range, 48-67 years). The pre- and post-operative radiographic parameters, such as percentage of slipping (PS), intervertebral space height, angle of slip (AS), thoracic kyphosis (TK), thoracolumbar junction angle (TLJ), sagittal vertical axis (SVA), lumbar lordosis (LL), spino-sacral angle (SSA), sacral slope (SS), pelvic tilt (PT), and pelvic incidence (PI) were measured. The functional evaluation was made using the Oswestry Disability Index (ODI). Pearson correlation were used to investigate the association between all parameters and ODI score. Results PS, intervertebral space height, AS, and ODI were improved significantly compared with properative ones (P lt; 0.05). Significant differences were found in the other parameters between pre- and post-operation (P lt; 0.05) except TLJ and TK. The alteration of SVA showed significant correlation with the changes of PS, PI, PT, LL, SS, AS, SSA, and ODI. The alteration of SSA showed significant correlation with the changes of PS, PI, LL, SS, AS, PT, and ODI. Conclusion Surgical posterior intervertebral fusion combined with pedicle screw fixation for low-grade isthmic spondylolisthesis can effectively improve and maintain the spinal sagittal parameters. SVA and SSA are adequate to evaluate pre-and post-operative balance. The good clinical outcome is closely related with the improved of SVA and SSA.
ObjectiveTo compare the effectiveness of vertebral arch replantation and laminectomy in the treatment of mild to moderate isthmic spondylolisthesis.MethodsThe clinical data of 66 patients with isthmic spondylolisthesis treated with vertebral arch replantation or laminectomy between March 2014 and July 2016 were retrospectively analyzed. They were divided into trial group (34 cases, treated with complete replantation of vertebral arch, intervertebral fusion, and internal fixation) and control group (32 cases, treated with laminectomy with intervertebral fusion and internal fixation) according to different surgical methods. There was no significant difference in general data of gender, age, disease duration, lesion segment, Meyerding grade, and preoperative visual analogue scale (VAS) score, Oswestry disability index (ODI) score, Japanese Orthopaedic Association (JOA) score between the two groups (P>0.05). The operation time, intraoperative blood loss, complications, vertebral arch fusion of trial group, and epidural scar formation of the two groups were recorded. The VAS score, JOA score, and ODI score were evaluated at preoperation, 3, 6, 12 months after operation, and at last follow-up. The effectiveness was evaluated according to HOU Shuxun’s criteria.ResultsAll the patients successfully completed the surgery, without any aggravation of nerve injury, dural tear, infection, etc. There was no significant difference in the operation time between the two groups (t=0.583, P=0.562), but the intraoperative blood loss was significantly lower in the trial group than that in the control group (t=2.134, P=0.037). All the 66 patients were followed up 13-18 months (mean, 16.2 months). Postoperative clinical symptoms of all patients were significantly improved. In the control group, 7 cases were found to have symptoms of spinal canal stenosis with postoperative posture changes at 3 months after operation, and 5 cases showed mild lower limb numbness at 18 months after operation. No complication such as infection and nerve injury occurred in other patients. In the trial group, 34 cases of epidural scar tissue were completely blocked outside the replantation vertebral arch, while in the control group, 11 cases of epidural scar tissue invaded the spinal canal. At last follow-up, the fusion rate of intervertebral bone grafting and vertebral arch replantation in the trial group was 100%, and the fusion rate of intervertebral bone grafting in the control group was also 100%. The VAS score, ODI score, and JOA score were significantly improved at each time point after operation (P<0.01). The ODI score and JOA score of the trial group were significantly better than those of the control group at 3 months after operation and at last follow-up (P<0.05), and there was no significant difference in scores between the two groups at other time points (P>0.05). According to HOU Shuxun’s criteria, the excellent and good rate was 91.2% in the trial group and 84.4% in the control group, showing no significant difference (χ2=1.092, P=0.573).ConclusionCompared with laminectomy, vertebral arch replantation can better improve postoperative neurological symptoms, maximize the reconstruction of the bone spinal canal, restore the stability of the intraspinal environment, and it is a better surgical method for lumbar isthmic spondylolisthesis.
ObjectiveTo evaluate the effectiveness of transforaminal lumbar interbody fusion (TLIF) via Luxor retractor associated with Mantis pedicle screw for the treatment of moderate or severe lumbar spondylol isthesis (LSL). MethodsA retrospective analysis was made on the cl inical data of 32 patients with LSL treated with TLIF via Luxor retractor associated with Mantis pedicle screw between June 2010 and June 2012. There were 20 males and 12 females, with the mean age of 48 years (range, 36-69 years). LSL occurred at the L4, 5 in 17 patients and at the L5, S1 in 15 patients. Of them, 18 cases were rated as Meyerding grade Ⅱ, and 14 cases as grade Ⅲ. The disease duration was 8 months to 6 years (mean, 3.5 years). The operation time, intraoperative blood loss, and preoperative and postoperative (1 week and 1 year) intervertebral height and sl ipping angle were recorded, and the sl ipping rate was calculated; Japanese Orthopaedic Association (JOA) score was used for cl inical efficacy assessment. ResultsThe operation time was 90-130 minutes (mean, 110 minutes); intraoperative blood loss was 120-300 mL (mean, 210 mL). Incisions healed by first intention. All patients were followed up 24-36 months (mean, 28 months), and no complications of leakage of cerebrospinal fluid and nerve root injury occurred; X-ray films showed satisfactory reduction of spondylolisthesis and good position of pedicle screw and interbody fusion cage. The mean bone fusion time was 4.0 months (range, 3.8-6.0 months). The JOA score, sl i pping rate, sl i pping angle, and intervertebral height at 1 week and 1 year after operation were significantly improved when compared with preoperative ones (P<0.05), but no significant difference was found between at 1 week and at 1 year after operation (P>0.05). ConclusionTLIF via Luxor retractor associated with Mantis pedicle screw fixation is a safe and effective minimally invasive technique in treating moderate or severe LSL.