Objective
To explore the feasibility and effectiveness of spinal pedicle screw internal fixation through endoscope-assisted posterior approach for the treatment of traumatic atlantoaxial instability.
Methods
Between September 2008 and September 2010, 44 patients with traumatic atlantoaxial instability received spinal pedicle screw internal fixation through endoscope-assisted posterior operation (micro-invasive surgical therapy group, n=22) or traditional surgical therapy (control group, n=22). There was no significant difference in gender, age, type of injury, disease duration, and preoperative Japanese Orthopedic Association (JOA) score between 2 groups (P gt; 0.05). The blood loss, operation time, length of the incision, improvement rate of JOA, and graft fusion rates were compared between 2 groups to assess the clinical outcomes.
Results
The blood loss, operation time, and length of the incision in the micro-invasive surgical therapy group were better than those in control group (P lt; 0.05). All incisions were primary healing. Of 88 pedicle screws, 7 pedicle screws penetrated into the interior walls of cervical transverse foramen in the micro-invasive surgical therapy group and 8 in the control group, but there was no syndrome of vertebral artery injury. All patients of the 2 groups were followed up 12 to 37 months (mean, 26 months). Bony fusion was achieved in all cases within 3 to 12 months (mean, 5.3 months). No loosening or breakage of screw occurred. At 6 months to 1 year after operation, the internal fixator was removed in 6 cases and the function of head and neck rotary movement were almost renewed. The JOA score was significantly improved at last follow-up when compared with preoperative score (P lt; 0.05), and no significant difference in JOA score and improvement rate between the 2 groups at last follow-up (P gt; 0.05).
Conclusion
The micro-invasive surgical therapy can acquire the same effectiveness to the traditional surgical therapy in immediate recovery of stability, high graft fusion rate, and less complication. Moreover, it can significantly reduce the operation time, blood loss, and soft tissue injury, so this approach may be an ideal way of internal fixation to treat traumatic atlantoaxial instability.
To explore the advantage and indication of combined anterior and posterior surgeries for lumbarsacral junction tuberculosis. Methods Eleven cases of the lumbarsacral junction tuberculosis were treated with combined anterior (radical debridement and autograft) and posterior (instrumentation and fusion) surgeries in one stage between January 2002 and December 2006. There were 9 males and 2 females with the age of 20-56 years old. The courseof disease was 4 to 15 months, 6 months on average. The lessons were located at L5, S1 in 7 patients, at L4,5, S1 in 2 patients and at L5, S2 in 2 patients. The involved vertebral bodies were at 2 segments in 7 patients; and 3 segments in 5 patients. The preoperative kyphosis was 5 to 8° with an average 9°. The sinus was associated in 3 patients, 3 patients had radiculopathy; 4 had paeumonophthisis and 9 had abscess. Results The followed-up period was from 6 months to 3 years, 18 months on average. According to Chen score, among the 11 cases, there were excellent in 9, good in 2. All incisions were healed up primarily. After operation, spinal fusion was achieved in 10 cases within 5 months to 7 months, 6 months on average, and pseudoarthrosis in 1 case was found by the CT examination. The postoperative kyphosis was 0 to 4° with the mean of 2° and the radiculopathy in 3 cases all got nerve function recovery. Conclusion Lumbarsacral junction tuberculosis treated with this surgical technique can achieve a high satisfactory rate with restoring the spinal stabil ity, arresting the disease early, providing early fusion, correcting the kyphosis and preventing progression of kyphosis particularly if lumbosacral spine tuberculosis is associated with sinus or preoperative diagnosis cannot exclude suppurative spondyl itis.
Objective To explore the feasibilities, methods, outcomes and indications of atlas pedicle screw system fixation and fusion for the treatment of upper cervical diseases. Methods From October 2004 to January 2006, 17 patients with upper cervical diseases were treated with atlas pedicle screw system fixation and fusion. There were 13 males and 4 females, ageing 19 to 52 years. Of 17 cases, there were 14 cases of atlantoaxial dislocation(including 3 cases of congenital odontoid disconnection，4 cases of old odontoid fracture，2 cases of new odontoid fracture(typeⅡC), 3 cases of rupture of the transverse ligament, and 2 cases of atlas fracture； 2 cases of tumor of C2; 1case of giant neurilemoma of C2,3 with instability after the resection oftumors. JOA score before operation was 8.3±3.0. Results The mean operative time and bleeding amount were 2.7 hours (2.1-3.4 hours) and 490 ml (300-750 ml) respectively. No injuries to the vertebral artery and spinal cord were observed. The medial-superior cortex of lateral mass was penetrated by 1 C1 screw approximately 3 mmwithout affecting occipito-atlantal motions. All patients were followed up 3-18 months. The clinical symptoms were improved in some extents and the screws were verified to be in a proper position, no breakage or loosening of screw and rob occurred. All patients achieved a solid bone fusion after 3-6 months. JOA score 3 months after operation was14.6±2.2. JOA improvement rates were 73%-91%(mean 82%). Conclusion The atlas pedicle screw system fixation and fusion is feasible for the treatment of upper cervical diseases and has betteroutcomes, wider indications if conducted properly.
Objective To investigate the cl inical outcomes of lumbar spondylol isthesis associated with lumbar spinal stenosis through decompressive laminectomy, spondylol ithesis reduction system (SRS) internal fixation, single posteriolateralVigor Spacer threaded fusion cages and intertransverse process arthrodesis bone grafting. Methods From June 2002 to June 2006, 58 cases of lumbar spondylol isthesis were treated with decompressive laminectomy, fixed by SRS instrumentation, posterior installed with interbody Vigor Spacer Cage and bone grafted between intertransverse process arthrodesis. There were 47 males and 11 females, aged 32-66 years old (45.8 on average). The course of disease was 3 months to 7 years, with an medium course of 25 months. Accoding to the Meyerding standard, 38 cases were classified as degree I and 20 as degree II. Spondylol isthesis between L4 and L5 covered 21 cases and between L5 and S1 covered 37 cases. There were 44 cases of lumbar spondylol isthesis and 14 of degenerative lumbar spondylol isthesis. The intervertebral height was 1.5-10.5 mm with the average of 5.1 mm. Results All patients’ incisions obtained heal ing by first intension after operation. The operation time was 50-90 minutes with an average of 65 minutes. The blood loss was 200-500 mL with an average of 250 mL. The patients were followed up for 10-38 months with an average of 23.6 months. According to the Macrab criteria, 54 cases were excellent, 3 good, 1 fair and the choiceness rate was 98.3%. According to the Meyerding classification, 38 cases of degree I and 19 out of 20 cases of degree II obtained complete reduction, and the rate of complete reduction was 98.3%. There were 57 (98.3%) cases which fused well 3-6 months after operation. The intervertebral height resumed to 9.6-12.5 mm with an average of 11.6 mm, and no intervertebral height loss was found. Conclusion The treatment of lumbar spondylol isthesis with decompressive laminectomy, SRS internal fixation, single posteriorolateral Vigor Spacer threaded fusion cage and bone grafting has excellent cl inical results and stable reduction.
Objective To evaluate pulmonary function changes in patients with severe scol iosis undergoing anterior release, posterior segmental fixation and fusion, and convex thoracoplasty by resecting a short length of rib. Methods FromJanuary 2006 to July 2007, 16 patients with severe scol iosis were treated with anterior release, posterior segmental fixation and fusion, and convex thoracoplasty by resecting a short length of rib. There were 6 males and 10 females with an average age of 16.9 years (range, 10-24 years). There were 1 case of Lenke 1 curve, 9 cases of Lenke 2 curve, and 6 cases of Lenke 4 curve. The preoperative Cobb angle was (104.8 ± 10.9)° and the preoperative thoracic kyphotic angle was (30.0 ± 4.2)°. The preoperative height of “razor back” deformity was (5.9 ± 1.2) cm. Before operation, the actual value of forced vital capacity (FVC) was (2.04 ± 0.63) L and that of forced expiratory volume in 1 second (FEV1.0) was (1.72 ± 0.62) L. The percentage of actual values to expected ones in FVC was 70% ± 16%, and that in FEV1.0 was 67% ± 15%. All patients had pulmonary function tests before operation and 3, 6, 12, 24 months after operation. Results All wounds healed by first intention. The Cobb angle at 24-month follow-up was (53.4 ± 18.6)° and the correction rate was 49.0% ± 15.3%. The thoracic kyphotic angle at 24-month follow-up was (34.0 ± 2.4)° and the correction rate was 13.3% ± 2.2%. The height of “razor back” deformity at 24-month follow-up was (2.2 ± 0.8) cm. Compared with preoperative level, all these data showed significant differences (P lt; 0.05). At 3 and 6 months, the actual values of FVC and FEV1.0 decl ined, but no significant difference was found (P gt; 0.05). At 12 and 24 months, the actual values of FVC andFEV1.0 were close to the preoperative level (P gt; 0.05). The percentages of actual values to expected ones in FVC and FEV1.0 indicate continued improvement in pulmonary function from the postoperative 3 to 24 months follow-up. Compared with preoperative level, the percentages of actual values in FVC decl ined 19% 3 months postoperatively (P lt; 0.05) and 12% 6 months postoperatively (P lt; 0.05). The percentages of actual values to expected ones in FEV1.0 decl ined 16% 3 months postoperatively (P lt; 0.05), and 10% 6 months postoperatively (P lt; 0.05). The percentages of actual values to expected ones in FVC and FEV1.0 were close to the preoperative level 12 and 24 months after operation (P gt; 0.05). Conclusion In severe scol iosis patients who are treated with anterior release, posterior segmental fixation and fusion, and convex thoracoplasty by resecting a short length of rib, pulmonary function decreases obviously 3-6 months after operation. And it returns to the operative baseline 12-24 months after operation.
Objective To compare the effectiveness of three different bone grafts [autogenous bone, allogeneic bone, and bone morphogenetic protein (BMP) composite bone] combined with screw system for spinal fusion of degenerative lumbardisease. Methods Between January 2005 and January 2010, 102 cases of degenerative lumbar disease were randomly treated with autogenous bone (group A, n=35), allogeneic bone (group B, n=33), and BMP composite bone (group C, n=34). There was no significant difference in sex, age, disease duration, affected segments, Meyerding grade, preoperative intervertebral space height, and the Japanese Orthopaedic Association (JOA) score among 3 groups (P gt; 0.05). The intervertebral space height, bone fusion rate, and JOA score were compared among 3 groups at different time points. Results All patients of 3 groups were followed up 2 to 5 years, with an average of 3.2 years. At 6 to 24 months after operation, the intervertebral space height significantly increased when compared with preoperative value in 3 groups (P lt; 0.05); the intervertebral space height of groups A and C was significantly greater than that of group B at 6, 12, 18, and 24 months after operation (P lt; 0.05), but no significant difference was found between groups A and C (P gt; 0.05). Bone graft fusion was observed at 6 months in groups A and C and at 12 months in group B; at 24 months, the rate of bone graft fusion was 100% in groups A and C, and 87.88% in group B, showing significant difference (P lt; 0.05). There was significant difference in JOA score between preoperation and postoperative 12th and 24th months (P lt; 0.05); at 12 and 24 months after operation, JOA socre and improving rate of groups A and C were significantly higher than those of group B (P lt; 0.05), but no significant difference was found between groups A and C (P gt; 0.05). Conclusion The effect of BMP composite bone is equivalent to that of autogenous bone graft in treating spinal fusion of degenerative lumbar disease, and they are better than allogeneic bone graft. BMP composite bone can obtain adequate bone grafts without invasive sampling, and has fast fusion and high successful rate.
Objective To study the properties of the xenogeneic deproteinized cancellous bone used as a scaffold in the bone tissue engineering andits application to the spinal fusion of the lumbar intertransverse process in agoat. Methods The deproteinized bone was derived from an adult pig’s femoral cancellous bone through the physical and chemical treatments. Its morphological features, constituting components, and biomechanical properties were examined by the scanning electron microscopy, X-ray diffraction analysis, and mechanical experimental instrument. The cell-material complex was observed under the inverted phase contrast microscope to evaluate the adhesion and the growth of the osteoblasts. The experimental model of the spinal fusion of the lumbar intertransverse process was produced in 12 male goats aged 6-8 months, which were divided into two groups. In Group A, the tissue engineered bone constructed by thexenogeneic deproteinized cancellous bone, the recombinant human bone morphogenetic protein 2, and the mesenchymal stem cells was used for the spinal fusion; however, in Group B the autoilium was used. The samples were harvested at 4, 8 and 12 weeks postoperatively, and a series of examinations were performed, including the radiography and the histomorphological assay. Results The deproteinized cancellous bone had a natural pore network system, with an aperture ranging in size from 200 to 500 μm, containing a main organic material ofcollagen and the inorganic material of hydroxyapatite. So, the deproteinized cancellous bone had a good mechanical strength and a good histocompatibility. In Group A, the X-ray examination at different timepoints postoperatively showed that at 4 weeks,the bridging areas of all the fusion sites were not clear, especially on the internal side; at 8 weeks, the upper and lower bridged parts had a narrowed gap, with formation of much continuous bony callus; at 12 weeks, a complete fusion occurred. In the early stage, the material density was slightly lowerin Group A than in Group B, but at 12 weeks the density was almost the same in both the groups. Histological examination in the transplant area showed that at 4 weeks in Group A there was a new bone formation in a multipoint way; at 8 weeks, a “sandwichshaped” new bone wascrossed with the transplanting materials; and at 12 weeks, a medullary cavity was remodeled and a new cancellous bone was formed. The osteogenic process of thetissue engineered bone constructed by the xenogeneic deproteinized cancellous bone scaffold was almost the same as the autoilium osteogenesis. Conclusion The xenogeneic deproteinized cancellous bone is a good material in the bone tissue engineering, which can be used as an osteogenesis scaffold andprovide a stable environment for revascularization and osteoblastic differentiation.
Objective To evaluate the biomechanical characteristicsof titanium mesh with anterior plate fixation or ilium autograft in anterior cervical decompression.Methods Six fresh cervical spine specimens(C3-7) of young cadaver were used in the biomechanical test. After C5, C5,6 and C4-6 were given vertebrectomy,ilium autograft and titanium mesh with anterior plate fixation were performed. Their stabilities of flexion,bilateral axial rotation,the lateral bending and the extension were tested. Intact cervical spine specimens served as control group. Results Ilium autograft improved the stability of the unstable cervical vertebrae and decreased the flexion, the lateral bending or the extension, showing a significant difference when compared with control group(Plt;0.05). Whereas, axial rotational motion was decreased insignificantly(Pgt;0.05). Titanium meshwith anterior plate fixation improved the stability of the unstable spine and decreased the flexion,the bilateral axial rotation,the lateral bending or the extension, showing a significant difference when compared with control group(Plt;0.05). Conclusion The vertebrectomy and anterior cervical fusion by ilium autograft was the least stable construct of all modes tested,and the titanium mesh implantation is stabler than the intact cervical sample.
Objective To investigate the osteoblasts effect, compl ications and influencing factors in the appl ication of small freeze-drying allogeneic bone plots mixed autologous bone fragments in spinal surgery, and to compare with autogenous bone graft. Methods From January 2003 to January 2007, 515 cases of spinal injuries were treated. A total of 324 cases weretreated with small freeze-drying allogeneic bone plots mixed with autologous bone grafts (group A), including 211 males and 113 females with an average age of 36 years (18-83 years). There were 182 cases of thoracolumbar vertebra fracture, 68 cases of lumbar spondylol isthesis, 47 cases of lumbar vertebral canal stenosis, 17 cases of cervical disc herniation, 5 cases of cervical spine fracture-dislocation and 5 cases of thoracolumbar vertebra tumor. The weight of bone graft was 10-60 g (mean 30 g). A total of 191 cases were treated with autogenous bone grafting (group B), including 135 males and 56 females with an average age of 32 years (23-78 years). There were 109 cases of thoracolumbar vertebra fracture, 23 cases of lumbar spondylol isthesis, 17 cases of lumbar vertebral canal stenosis, 19 cases of cervical disc herniation, and 23 cases of cervical spine fracture-dislocation. The weight of bone graft was 10-50 g (mean 25 g). Results In group A, effusion of wound increased in 4 cases and the result of bacterial culture was negative; effusion was absorbed after 2 weeks of local irrigation, drainege and cortin management. In group B, no obvious effusion was observed. The follow-up time was 10-36 months (mean 17.4 months) in group A and 8-36 months (mean 16.8 months) in group B. The bone heal ing was achieved in 308 cases within 4-10 months (mean 8.1 months) and in 184 cases within 4-10 months (mean 5.8 months), and the bone fusion rates were 95.06% and 96.34% in groups Aand B, respectively. There was no significant difference in bone fusion rate between groups (P gt; 0.05). According to Mankin and Komender evaluation standard, the response rates were 95.06% and 96.34% in groups A and B, respectively, showing no significant difference (P gt; 0.05). Conclusion Mix-bone grafting has the same effective to autologous bone grafting in bone fusion rate. It could be used as the supplement of the autologous bone inadequacy.
Objective To analyze the cl inical features of scol iosis associated with Chiari I malformation in adolescent patients, and to explore the val idity and safety of one-stage posterior approach and vertebral column resection for the correction of severe scol iosis. Methods Between October 2004 and August 2008, 17 adolescent patients with scol iosis associated with Chiari I malformation were treated with surgical correction through posterior approach and pedicle instrumentation. There were 9 males and 8 females with an average age of 15.1 years (range, 12-19 years). The MRI scanning showed that 16 of 17 patients had syringomyel ia in cervical or thoracic spinal cord. Apex vertebra of scol iosis were located atT7-12. One-stage posterior vertebral column resection and instrumental correction were performed on 9 patients whose Cobb angle of scol iosis or kyphosis was more than 90°, or who was associated with apparent neurological deficits (total spondylectomy group). Other 8 patients underwent posterior instrumental correction alone (simple correction group). All patients’ fixation and fusion segment ranged from upper thoracic spine to lumbar spine. Results The operative time and the blood loss were (384 ± 65) minutes and (4 160 ± 336) mL in total spondylectomy group, and were (246 ± 47) minutes and (1 450 ± 213) mL in simple correction group; showing significant differences (P lt; 0.05). In total spondylectomy group, coagulation disorder occurred in 1 case, pleural perforation in 4 cases, and lung infection in 1 case. In simple correcction group, pleural perforation occurred in 1 case. These patients were improved after symptomatic treatment. All patients were followed up 24-36 months (32.5 months on average). Bony heal ing was achieved at 6-12 months in total spondylectomy group. No breakage or pull ingout of internal fixator occurred. The angles of kyphosis and scol iosis were significantly improved at 1 week after operation (P lt; 0.01) when compared with those before operation. The correction rates of scol iosis and kyphosis (63.4% ± 4.6% and 72.1% ± 5.8%) in total spondylectomy group were better than those (69.4% ± 17.6% and 48.8% ± 19.3%) in simple correction group. Conclusion Suboccipital decompression before spine deformity correction may not always be necessary in adolescent scol iosis patients associated with Chiari I malformation. In patients with severe and rigid curve or apparente neurological deficits, posterior vertebral column resection would provide the opportunity of satisfied deformity correction and decrease the risk of neurological injury connected with surgical correction.
