Objective To review the research progress of the risk factors for slip progression and the pathogenesis of lumbosacral spondylolisthesis, and to discuss the value of Spinal Deformity Study Group (SDSG) classification system for lumbosacral spondylolisthesis. Methods Recent articles about the risk factors for slip progression and the pathogenesis of lumbosacral spondylolisthesis were reviewed and comprehensively analyzed with SDSG classification system of lumbosacral spondylolisthesis. Results Pelvic incidence (PI) is the key pathogenic factor of lumbosacral spondylolisthesis. The Meyerding grade of slip, PI, sacro-pelvic balance, and spino-pelvic balance not only are the fundamental risk factors of slip progression, but also are the key factors to determine how to treat and influence the prognosis. Therefore, compared with Wiltse, Marchetti-Bartolozzi, and Mac-Thiong-Labelle classification systems of lumbosacral spondylolisthesis, SDSG classification based on these factors mentioned above, has better homogeneity between the subjects of subgroup, and better reliability, moreover, could better guide operative plan and judge the prognosis. Conclusion It is suggested that the SDSG classification system should be the standard classification for lumbosacral spondylolisthesis for the clinical and research work.
Objective To explore an improved surgical approach to the superior posterior partial resection of the fractured vertebral body followed by the single segmental fusion to treat lumbar burst fracture and to evaluate its preliminary clinical application. Methods From June to October 2006, 4 patients (2 males, 2 females; age, 17-39 years) with Denis B type lumbar burst fracture underwent the superior posterior partial resection of the fractured vertebral body followed by the single segmental fusion. The fracture occurred in 2 patients at L1 and 2 at L2. According to the Frankel scales assessment, before operation, 2patients were at Grade B and the other 2 at Grade C, and the visual analogue scale (VAS) was 7.00±0.82. Radiological evaluation was performed, which revealed the kyphosis Cobb angel of 22.94±11.21°, the adjacent superior and the inferiorintervertebal disc heights of 12.78±1.52 mm and 11.68±1.04 mm, espectively, and the vertebral canal sagittal diameter of 9.56±2.27 mm on the computer tomography (CT) scan. The neurological and the radiological evaluations were also made immediately and 3 months after operation. Results The anterior single segmental decompression and fusion operations were performed successfully in all the patients. The average operating time was 166±29 min and the average amount of blood loss was 395± 54 ml. The Frankel scales assessment showed that at the time immediately after operation, one of the 2 Grade B patients had an improvement to Grade C, but the other patient had no improvement. One of the 2 Grade C patientshad an improvement to Grade D, but the other patient had no improvement. Three months after operation, the 2 Grade B patients had an improvement to Grade C. The 2 grade C patients had an improvement to Grade D or E. The VAS score was significantly decreased to 3.50±1.29 after operation and to 1.25±0.50 3 months later （P＜0.05）. The vertebral canal sagittal diameter was significantly increased to 19.76±3.82 mm (Plt;0.01), but it was maintained to 19.27±3.41 mm3 months later, with no significant difference（Pgt;0.05）. The patients’ kyphosis Cobb angle was significantly improved to 8.71±5.41° (P＜0.05) , but it was maintained to 9.52±5.66° 3 months later, with no significant difference（Pgt;0.05）. The heights of the adjacent discs remained unchanged. No complication was observedduring and after operation, and the radiological and the CT scanning evaluations 3 months later showed no failure of the internal fixation. Conclusion The superior and posterior partial resection of the fractured vertebral body followedby the single segmental fusion can effectively decompress the vertebral canal and maintain the spine stability in treatment of the Denis B type fracture thoughthe longterm effectiveness requires a further follow-up.
OBJECTIVE: To provide a better treatment method of lumbar stenosis and root pain resulting from simple hypertrophy of ligamentum flavum. METHODS: By studying the records of 143 lumbar pain cases, we found 5 cases caused by simple hypertrophy of ligamentum flavum. All the patients were old man with a long progressed history. There was little difference of clinical features between the disc herniation and hypertrophy of ligamentum flavum. All cases accepted resection of ligamentum flavum. RESULTS: All the symptoms were relieved postoperatively. The patients could walk. CONCLUSION: The degeneration of lumbar ligamentum flavum can cause lumbar stenosis and root pain. Resection of ligamentum flavum can relieve the symptom.
OBJECTIVE To investigate the effect of acid fibroblast growth factor (aFGF) on guided bone regeneration (GBR), to study whether aFGF can promote the repairing ability of GBR in bone defect. METHODS 10 mm long segmental defects were created in the diaphyses of both radii in 16 New Zealand rabbits. The defect was bridged with a silicon tube. Human recombinant aFGF was instilled into the tube on the experimental side, while the contralateral tube was instilled with saline as control group. The radiographic, gross and histologic examination of the samples were analyzed at 2, 4, 6 and 8 weeks after operation. RESULTS On the experimental side, there was new bone formation in the bone medullary cavity, the endosteum and the section surface of the cortex at 2 weeks. At 4 weeks, at the center of the blood clot in the tube there was new bone formation and bone defect was completely healed at 8 weeks. On the control side, new bone formation was less in every period compared with that of the experimental side. At 8 weeks, there was only partial healing of the bone defect. CONCLUSION It can be concluded that aFGF can promote new bone formation and facilitate GBR in bone defect.
Objective To investigate the influence of Nogo extracellular peptide residues 1-40 (NEP1-40) gene modification on the survival and differentiation of the neural stem cells (NSCs) after transplantation. Methods NSCs were isolated from the cortex tissue of rat embryo at the age of 18 days and identified by Nestin immunofluorescence. The lentiviruses were transduced to NSCs to construct NEP1-40 gene modified NSCs. The spinal cords of 30 Sprague Dawley rats were hemisected at T9 level. The rats were randomly assigned to 3 groups: group B (spinal cord injury, SCI), group C (NSCs), and group D (NEP1-40 gene modified NSCs). Cell culture medium, NSCs, and NEP1-40 gene modified NSCs were transplanted into the lesion site in groups B, C, and D, respectively at 7 days after injury. An additional 10 rats served as sham-operation group (group A), which only received laminectomy. At 8 weeks of transplantation, the survival and differentiation of transplanted cells were detected with counting neurofilament 200 (NF-200), glial fibrillary acidic portein (GFAP), and myelin basic protein (MBP) positive cells via immunohistochemical method; the quantity of horseradish peroxidase (HRP) positive nerve fiber was detected via HRP neural tracer technology. Results At 8 weeks after transplantation, HRP nerve trace showed the number of HRP-positive nerve fibers of group A (85.17 ± 6.97) was significantly more than that of group D (59.25 ± 7.75), group C (33.58 ± 5.47), and group B (12.17 ± 2.79) (P lt; 0.01); the number of groups C and D were significantly higher than that of group B, and the number of group D was significantly higher than that of group C (P lt; 0.01). Immunofluorescent staining for Nestin showed no obvious fluorescence signal in group A, a few scattered fluorescent signal in group B, and b fluorescence signal in groups C and D. The number of NF-200-positive cells and MBP integral absorbance value from high to low can be arranged as an order of group A, group D, group C, and group B (P lt; 0.05); the order of GFAP-positive cells from high to low was group B, group D, group C, and group A (P lt; 0.05); no significant difference was found in the percentage of NF-200, MBP, and GFAP-positive cells between group C and group D (P gt; 0.05). Conclusion NEP1-40 gene modification can significantly improve the survival and differentiation of NSCs after transplantation, but has no induction on cell differentiation. It can provide a new idea and reliable experimental base for the study of NSCs transplantation for SCI.
Objective To investigate short-term effectiveness of spinal navigation with the intra-operative three-dimensional (3D)-imaging modality in pedicle screw fixation for congenital scoliosis (CS). Methods Between July 2010 and December 2011, 26 patients with CS were treated. Of 26 patients, 13 patients underwent pedicle screw fixation using the spinal navigation with the intra-operative 3D-imaging modality (navigation group), while 13 patients underwent the conventional technique with C-arm X-ray machine (control group). There was no significant difference in gender, age, hemivertebra number and location, major curve Cobb angle, and Risser grade between 2 groups (P gt; 0.05). Operation time, operative blood loss, frequency of the screw re-insertion, and postoperative complication were observed. The pedicle screw position was assessed by CT postoperatively with the Richter’s standard and the correction of Cobb angle was assessed by X-ray films. Results All patients underwent the surgery successfully without major neurovascular complication. There was no significant difference in operation time, operative blood loss, and pedicle screw location between 2 groups (P gt; 0.05). A total of 58 screws were inserted in navigation group, and 3 screws (5.2%) were re-inserted. A total of 60 screws were inserted in control group, and 10 screws (16.7%) were re-inserted. There was significant difference in the rate of pedicle screw re-insertion between 2 groups (χ2=3.975, P=0.046). Patients of navigation group were followed up 6-24 months, and 6-23 months in control group. According to Richter’s standard, the results were excellent in 52 screws and good in 6 screws in navigation group; the results were excellent in 51 screws, good in 5 screws, and poor in 4 screws in control group. Significant difference was found in the pedicle screw position between 2 groups (Z= — 1.992, P=0.046). The major curve Cobb angle of 2 groups at 1 week and last follow-up were significantly improved when compared with preoperative value (P lt; 0.05), but there was no significant difference between 1 week and last follow-up (P gt; 0.05). No significant difference in correction rate of the major curve Cobb angle was found between 2 groups at last follow-up (t=0.055, P=0.957). Conclusion Spinal navigation with the intra-operative 3D-imaging modality can improve the accuracy of pedicle screw implantation in patients with CS, and effectually reduce the rate of screw re-insertion, and the short-term effectiveness is satisfactory.
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 assess the mid-term effectiveness of anterior decompression and fusion with nano-hydroxyapatite/polyamide 66 (n-HA/PA66) cage in treatment of cervical spondylotic myelopathy. Methods A retrospective study was made on 48 patients with cervical spondylotic myelopathy who underwent anterior decompression and fusion with n-HA/PA66 cage between August 2008 and January 2010. There were 33 males and 15 females with an average age of 54.5 years (range, 42-72 years). The disease duration was 3-12 months (mean, 6 months). The affected segments included 35 cases of single segment (C3, 4 in 7, C4, 5 in 18, and C5, 6 in 10) and 13 cases of double segments (C3-5 in 7 and C4-6 in 6). Of 48 patients, 28 was diagnosed as having intervertebral disc protrusion, 12 as having ossification of posterior longitudinal ligament, and 8 as having vertebral osteophyte; 35 patients underwent single segmental anterior corpectomy and fusion, and 13 patients underwent single segmental anterior discectomy and fusion. The pre- and post-operative radiographs (cervical anteroposterior and lateral X-ray films and three-dimensional CT scans) were taken to measure the segmental height and lordosis angle. Brantigan et al assessment standard and visual analogue scale (VAS) and Japanese Orthopaedic Association (JOA) scores were used to evaluate the graft fusion and the improvement of clinical symptoms, respectively. Results All patients were followed up for 46 months on average (range, 36-54 months). No cage breaking, displacement, or sliding was found. At last follow-up, 36 cases were rated as Brantigan grade E, 10 cases as grade D, and 2 cases as grade C; the fusion rate was 96%. Both segmental height and lordosis angle were corrected significantly at immediate and 6 months after operation and last follow-up than those before operation (P lt; 0.05), but no significant difference was found among different time points after operation (P gt; 0.05). At last follow-up, the cage subsidence was (1.3 ± 1.0) mm. The VAS and JOA scores at 6 months after operation and last follow-up were significantly improved when compared with preoperative scores (P lt; 0.05), and the scores at last follow-up were superior to ones at 6 months after operation (P lt; 0.05). Conclusion The mid-term effectiveness of anterior decompression and fusion with the n-HA/PA66 cage in patients with cervical spondylotic myelopathy is satisfactory because it can effectively restore and maintain segmental height and lordosis angle and promote osseous fusion.
【 Abstract】 Objective To construct a lentiviral expression vector carrying Nogo extra cellular peptide residues 1-40(NEP1-40) and to obtain NEP1-40 efficient and stable expression in mammalian cells. Methods The DNA fragment ofNEP1-40 coding sequence was ampl ified by PCR with designed primer from the cDNA l ibrary including NEP1-40 gene, and then subcloned into pGC-FU vector with in-fusion technique to generate the lentiviral expression vector, pGC-FU-NEP1-40. The positive clones were screened by PCR and the correct NEP1-40 was confirmed by sequencing. Recombinant lentiviruses were produced in 293T cells after the cotransfection of pGC-FU-NEP1-40， and packaging plasmids of pHelper 1.0 and pHelper 2.0. Green fluorescent protein (GFP) expression of infected 293T cells was observed to evaluate gene del ivery efficiency. NEP1-40 protein expression in 293T cells was detected by Western blot. Results The lentiviral expression vector carrying NEP1-40 was successfully constructed by GFP observation， and NEP1-40 protein expression was detected in 293T cells by Western blot. Conclusion The recombinant lentivirus pGC-FU-NEP1-40 is successfully constructed and it lays a foundation for further molecular function study of NEP1-40.
Objective To evaluate the short-term effectiveness of nano-hydroxyapatite/polyamide-66 (n-HA/PA66) intervertebral cage for lumbar interbody fusion in the patients with lower lumbar degenerative diseases. Methods Between January and October 2011, 20 patients with lower lumbar degenerative diseases underwent transforaminal lumbar interbody fusion with n-HA/PA66 intervertebral cage. There were 8 males and 12 females, aged 22-80 years (mean, 51 years). The disease duration was 1 to 24 months (mean, 4 months). L4, 5 fusion was performed in 8 cases, L5, S1 fusion in 9 cases, and L4-S1 fusion in 3 cases. Among 20 cases, 3 were diagnosed as having recurrent lumbar disc protrusion, 5 as having lumbar degenerative spondylolisthesis, 9 as having lumbar isthmic spondylolisthesis, and 3 as having lumbar spinal stenosis. The intervertebral height and lordosis were measured on X-ray film to assess the surgical correction and postoperative sustain while osseous fusion was observed on 3-dimensional CT. The Oswestry disability index (ODI) and short-form 36 health survey scale (SF-36) scores were obtained to assess the status of clinical recovery. Results All patients had incision healing by first intention. The pain and numb were relieved in varying degrees after operation. No cerebrospinal leakage, nerve root injury, or wound infection was occurred. All patients were followed up 6-9 months (mean, 7 months). No cage displacement or collapse was found. The intervertebral height and lordosis of single fusion segment were significantly improved at 3 days and 3, 6 months after operation when compared with those at preoperation (P lt; 0.01); there was no significant difference among each time point after operation (P gt; 0.05). The fusion rate was 74% at 3 months after operation and 96% at 6 months after operation, with an average of 4 months (range, 3-9 months) for interbody fusion. The ODI and SF-36 scores were significantly improved at 3 days and 6 months after operation when compared with the scores at preoperation (P lt; 0.01); there was no significant difference among each time point after operation (P gt; 0.05). Conclusion The interbody fusion with n-HA/PA intervertebral cage is effective and safe to treat the lower lumbar degenerative diseases. The n-HA/PA66 intervertebral cage is an ideal device of interbody fusion with high fusion rate, low subsidence rate, and high transmission X-ray, but the long-term effectiveness need further observation.