Objective To assess the effectiveness of single-level lumbar pedicle subtraction osteotomy for correction of kyphosis caused by ankylosing spondylitis. Methods Between July 2006 and July 2010, 45 consecutive patients with kyphosis caused by ankylosing spondylitis underwent single-level pedical subtraction osteotomy. There were 39 males and 6 females with an average age of 36.9 years (range, 21-59 years). The average disease duration was 18.6 years (range, 6-40 years). All patients had low back pain, fatigue, abnormal gaits, and disability of looking and lying horizontally. Radiological manifestations included sacroiliac joints fusion, bamboo spine, pelvic spin, and kyphosis. Cervical spine was involved in 30 patients; thoracolumbar spine was affected in 15 patients. Results Wound hydrops and dehiscence occurred in 1 case, and was cured after debridement; primary healing of incision was obtained in the other patients. Two patients had abdominal skin blisters, which were cured after magnesium sulfate wet packing. Forty-two patients were followed up 24-74 months (mean, 30 months). All osteotomy got solid fusion. The average bony fusion time was 6.8 months (range, 3-12 months). All patients could walk with brace and looked or lied horizontally postoperatively. The Scoliosis Research Society-22 Patient Questionnaire (SRS-22) score, T1-S1 kyphosis Cobb angle, L1-S1 lordosic Cobb angle, sagittal imbalance distance, and chin-brow vertical angle at 1 week and last follow-up were significantly improved when compared with those at preoperation (P lt; 0.05), but no significant difference was found between at 1 week and last follow-up (P gt; 0.05). Conclusion Single-level pedicle subtraction osteotomy has satisfactory effectiveness for the correction of kyphosis caused by ankylosing spondylitis.
Objective To review the research progress of stress fracture of the lumbar pedicle. Methods The literature about the stress fracture of the lumbar pedicle was reviewed extensively and summarized. Results There are two types of stress fracture: fatigue and structure insufficient. Stress fracture of lumbar pedicle occurred mainly in the crowd with repetitive and large activities of spine, contralateral spondylolysis, or previous surgery of lumbar vertebra. The main stresses causing stress fracture of the lumbar pedicle are shear stress and twisting stress, followed by sudden hyperflexion or hyperextension of the spine. Stress fracture of lumbar pedicle was easily missed by conventional X-ray examination, usually XCT, MRI, or bone scan was needed to confirm the diagnosis. It is divided into 4 types or 4 periods according to MRI findings: stress reaction, incomplete fracture, complete fracture, and pseudarthrosis. For patients with incomplete, complete, and juvenile stress fractures of the lumbar pedicle without nerve root irritation, the majority of claims preferred conservative treatment and the healing rate of fracture was high; for patients with bilateral pseudarthrosis and with nerve root irritation as well as patients who failed to the conservative treatment, surgical management was advocated and the operation result is good. Conclusion Stress fracture of the lumbar pedicle as one of the causes of low back pain is extremely rare, and is easily missed clinically. Surgery or conservative management should be selected based on type of fracture and specific condition of the patient, the treatment results are satisfactory.
Objective To elucidate the new development, structural features and appl ication of the lumbar interspinous process non-fusion techniques. Methods With the review of the development course and important research works in the field of the lumbar inter-spinous process non-fusion techniques, the regularity summary, science induction, and prospect were carried out. Results The lumbar inter-spinous process non-fusion technique was a part of non-fusion insertof spinal division posterior surface. According to the design, it could be divided into two major categories: dynamic and static systems. The dynamic system included Coflex and device for intervertebral assisted motion; the static system included X-STOP, ExtenSure and Wall is. The lumbar inter-spinous process non-fusion technique was a new technique of spinal division, it could reserve the integrated function of intervertebral disc and zygapophysial joint, maintain or recover the segmental movement to a normal level, and have no adverse effect on the neighboring segments. A lot of basic and cl inical researches indicated that lumbar inter-spinous process insert had extensive appl ication to curatio retrogression lumbar spinal stenosis, discogenic low back pain, articular process syndrome, lumbar intervertebral disc protrusion and lumbar instabil ity and so on. Conclusion With the matures of lumbar inter-spinous process non-fusion techniques and the increased study of various types of internal fixation devices, it will greatly facil itate the development of treatment of lumbar degenerative disease. But long-term follow-up is needed to investigating the long-term efficacy and perfect operation indication.
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.
Objective To explore the feasibil ity and efficacy of percutaneous kyphoplasty (PKP) for the treatment of severe osteoporotic vertebral compression fracture (OVCF), and to assess the cl inical result of the PKP technique. Methods From May 2006 to October 2007, 12 patients with severe OVCF affecting more than 2/3 of the original vertebral body height were treated by using domestic PKP and percutaneous vertebroplasty (PVP) tool systems. There were 3 malesand 9 females, with the age of 56-82 years and a mean disease course of 4.2 months (1-49 months). Eleven thoracic vertebra and 4 lumbar vertebra suffered from severe vertebral compression fractures, which included 3 extremely severe thoracic OVCF. Four thoracic vertebra and 3 lumbar vertebra had not severe OVCF. There were 4 cases of single vertebral compression fracture, 6 cases of double fractures, and 2 cases of triple fractures. Only single side PKP and PVP were performed via extrapedicular approach in thoracic vertebra, and via transpedicular approach in lumbar spine under fluoroscopic control. Eight patients with severe thoracic compression fractures and 4 with severe lumbar fractures were treated by PKP. Four patients with relatively mild thoracic compression fractures and 3 with lumbar fractures were treated by PVP. Results The operation was successfully, 3 patients with extremely severe thoracic compression fractures received no intervention. The maximum expansion pressure of balloon was (1 068 ± 298) kPa, and the volume was (3.1 ± 1.2) mL during operation. The average operative time of PKP was (44.9 ± 10.6) minutes per vertebra, while the average operative time of PVP was (36.5 ± 6.8) minutes per vertebra. The average volume of injected bone cement was (2.5 ± 0.6) mL per thoracic vertebra, and (3.6 ± 1.2) mL per lumbar vertebra. The mean hospitalization time were (3.7 ± 1.6) days. Twelve cases were followed up 5-18 months (mean 8.6 months). The visual analogue scale scoreswere (2.35 ± 0.61) points 2 days after operation and (2.89 ± 1.07) points at last follow-up, there were statistically significant differences when compared with before operation (8.27 ± 1.36) points (P lt; 0.01). Extravertebral leakage of the bone cement into the paravertebral tissue and/or disc occurred in 6 patients (9 vertebra) without significant symptom. Conclusion One side approach PKP is a safe and effective technique for treatment of severe OVCF with markedly rel ief of pain.
Objective To investigate the cl inical appl icabil ity and value of internal fixator for the reconstruction of lumbar isthmus in the treatment of lumbar vertebral spondylolysis and to lay a fundation for its cl inical appl ication. Methods Sixteen healthy goats weighing 22.65-31.22 kg were selected to establ ish the models of vertebral spondylolysis at L5, which thereafter were randomized into two groups (n=8): bone graft group in which 0.8-1.1 g fresh autogenous bone was transplanted into the isthmus spondylolysis area, and internal fixation with bone graft group in which internal fixator was installed before transplanting 0.8-1.1 g fresh autogenous bone into the isthmus spondylolysis area. All animals were killed 8 weeks after operation to receive imaging, topographic anatomy and histology detection. Meanwhile, biomechanics test was performed by using 5 donated vertebral body specimens (4 males and 1 female aged 35-51 years old). The left isthmus of L5 vertebra was transected to serve as lumbar vertebral spondylolysis model. A mini-displacement sensor was put at the transected ends of the isthmus. Then loading was conducted with a constant velocity of 2 mm/min by electronic omnipotent tester simulating the direction of fixation force of the internal fixator, and the deformation value of the transected ends was collected by a dynamic data collector and analyzer. The loading wascontinued until the vertebra specimens were damaged. The deformation of displacement sensor and the closure of transected ends of the lumbar isthmus were observed. Results All the goats behaved normally shortly after operation, and no nerve injury induced by operation and no wound infection occurred. Bilaterally obl ique X-ray films of lumbar vertebra and topographic anatomy 8 weeks after operation showed the fusion rate of the internal fixation and bone graft group and the bone graft group was 100% and 62.5%, respectively, indicating there was a significant difference (P lt; 0.05). Histology observation showed 3 goats in the bone graft group presented empty bone trabecula, empty bone lacuna and the disappearance of osteocytes at the transected ends of lumbar isthmus; while in the internal fixation and bone graft group, the bone trabecula grew into cancellous structures with hematopoietic and fatty bone marrow tissue inside, and parts of the bone trabecula had various degrees of mosaic-l ike pattern. During the upload, the biomechanics test and data processing results showed when the external load was 40 N, the deformation of displacement sensor was identified and the gap between the transected ends of lumbar isthmus started to close; then with the increase of external load, the displacement sensor tended to ascend in a l inearity manner; while when the external load was 212 N, the displacement sensor had no further deformation, the gap between the transected ends of lumbar isthmus wascompletely closed, and the pressor effect appeared. Conclusion The internal fixator for the reconstruction of lumbar isthmus has mechanical effects of stabil izing and elevating pressure with a high fusion rate.
Objective To analyze the cl inical effects of modified transforaminal lumbar interbody fusion (TLIF) for the treatment of lumbar degenerative disease. Methods From October 2003 to December 2006, 33 patients with lumbar degenerative disease (L3-S1) were treated by modified TLIF. There were 14 males and 19 females with an average age of 52.2 years(33 to 70 years). The median disease course was 1.8 years (4 months to 15 years). A total of 42 levels were fused, including 24 cases of single level and 9 cases of double levels. The results of preoperative diagnosis were lumbar degenerative spondylol isthesis with stenosis (8 cases), isthmic spondylol isthesis (5 cases), degenerative lumbar stenosis (16 cases), huge herniated disc with segmental instabil ity (3 cases) and failed back surgery syndrome (1 case). During the modified TLIF procedure, total inferior facet process and inner half summit of superior facet process of TLIF side were resected to make the posterior wall of foramen opened partly. After the bone graft (3 to 5 mL) was placed into the interbody space, a single rectangle Cage was inserted obl iquely from 30° to 40° toward the midl ine. Combined with pedicle screw instrumentation, TLIF was accompl ished. Middle canal and opposite side nerve root decompression were performed simultaneously when necessary. Results Intraoperative dura mater rupture, postoperative cerebral spinal fluid leakage, deep wound infection and transient nerve root stimulation occurredin 1 case respectively, and were all recovered after treatment. No patients had permanent neurologic deficit or aggravation. All patients were followed up for 20 to 58 months (mean 27.2 months). At the follow-up after 1 year postoperatively, all the operated segments achieved fusion standard and no broken screw or Cage dislocation occurred. All 13 cases of spondylol isthesis were reduced thoroughly and maintained satisfactorily. Nineteen patients remained sl ight chronic back pain. There was significant difference (P lt; 0.05) in JOA score between preoperation (14.9 ± 5.1) and postoperation (25.9 ± 3.0). The rate of cl inical improvement was 80.5% (excellent in 24 cases, good in 7 cases, and fair in 2 cases). Conclusion The modified TLIF carries out the less invasive principles in opening operations, simpl ifies the manipulation and expands the indication of TLIF to some extent, and the cl inical results for the treatment of lumbar degenerative disease is satisfactory.
Objective To evaluate the cl inical outcomes of anterior decompression, bone graft and internal fixation in treating fourth lumbar burst fractures with il iac fenestration. Methods From February 2001 to May 2006, 8 cases of fourth lumbar burst fractures were treated by anterior decompression, correction, reduction, il iac autograft, Z-plate internal fixation with il iac fenestration. Of them, there were 7 males and 1 female, aging 24-46 years with an average of 29.3 years, including 3 cases of Denis type A and 5 cases of Denis type B. The decompression, intervertebral height were compared betweenpreoperation and postoperation by CT scanning. According to Frankel assessment for neurological status, 2 cases were at grade C, 5 at grade D and 1 at grade E before operation. Four cases had different degrees of disturbance of sphincter. Time from injury to operation was 8 hours to 11 days. The preoperative height of the anterior border of the L4 vertebral body was (13.8 ± 2.3) mm, the Cobb angel of fractured vertebral body was (13.2 ± 2.5)°, the vertebral canal sagittal diameter of L4 was (10.6 ± 3.5) mm. The bone graft volume was (7.5 ± 1.3) cm3 during operation. Results Operations were performed successfully. The mean operative time was (142 ± 25) minutes and the mean amount of blood loss was (436 ± 39) mL. The incisions obtained heal ing by first intention after operation. Two cases suffered donor site pain and recevied no treatment. The follow-up time of 8 cases was from 21 months to 52 months (mean 24.5 months). At one week after operation, the height of the anterior border of the L4 vertebral body was (32.5 ± 2.6) mm, the Cobb angel of fractured vertebral body was (6.8 ± 3.7)°, and the vertebral canal sagittal diameter of L4 was (19.8 ± 5.1) mm, showing significant difference when compared with those of preoperation (P lt; 0.01). At the final follow-up, the results showed that the pressure was reduced sufficiently, all autograft fused well, the neurological status improved at Frankel grade from C to D in 1 patient, from D to E in 3 patients, but the others had no improvement. In 4 patients who had disturbance of sphincter, 3 restored to normal and 1 was better off. Conclusion Cl inical outcomes of anterior surgery for fourth lumbar burst fractures with il iac fenestration are satisfactory. It can facil icate operation, reduce the pressure sufficiently, maintenance intervertebral height and recover the neurological function.
To evaluate the appl ication value of internal fixation of spinal column by posterior approach and extraperitioneal bilateral focal debridement for the treatment of tuberculosis of lumbosacral vertebral body. Methods From March 2000 to February 2005, 16 cases of spinal tuberculosis in L3-S1 were treated with internal fixation of spinal column by posterior approach and extraperitioneal bilateral focal debridement. Sixteen cases included 11 males and 5 females, and the age was 21-56 years. The locations of spinal tuberculosis were L3 in 4 cases, L4 in 6, L5 in 4, and S1 in 2. The course of disease averaged 13 monthes (range 6 monthes to 6 years). The ESR of all cases was greater than 20 mm/h (average40 mm/h); WBC was normal in 14 cases, and a l ittle high in 2 cases. The X-ray picture showed narrow intervertebral space in 5 cases, compressed body of vertebra in 7 cases, and destroyed 2 consecutive vertebra and its sclerotin was condupl icate in 1 case. All cases were abscess in major psoas muscle. The CT showed destruction of bone, abscess-formation and dead bone in body of vertebra of 16 cases. The abscess were found in vertebral canal in 5 cases and dura mater of spinal cord and spinal nerve root crushed in 2 cases. The MRI showed destruction of bone, abscess-formation and hibateral abscess in major psoas muscle in 11 cases. The abscess were found in vertebral canal and dura mater of spinal cord and spinal nerve root crushed in 6 cases. The therapy of pasid was treated after operation in all the cases. Results Incision healed by first intention in 16 cases; and disruption of wound occurred and heal ing was achieved after symptomatic treatment in 1 case. Sixteen cases were followed up 2-5 years (29 months on average). Among all the cases, anaesthesia in double thigh was found in 3 cases, adynamia of dorsiflexion in foot in 1 case, gatism in 1 case; after 2 weeks the symptoms were vanished. Indirect hernia of fold inguen were found in 1 case after 2 years, and the patient refused operation for age and was no longer followed up. Fuzzy, exsic and acerb in eyes were foundin 6 cases, hearing disturbance were found in 2 cases, and symptoms were vanished after medication adjustment. Low-grade fever and lumbar myalgia were found in 1 case and cured after staying in bed and medication adjustment. All ESR were normal, synostosis of lumbosacral vertebral body was found in 13 cases, kyphosis in 1 case. Conclusion Internal fixation of spinal column by posterior approach and extraperitioneal bilateral focal debridement is safe and available way for the treatment of tuberculosis of lumbosacral vertebral body, it can save the times of operation, shorten period and enhance effect of treatment.
Objective To review the current development of the dynamic stabilization devices and their biomechanics as well as clinical application.Methods The related biomedical research papers at home and abroad were consulted and analyzed Results There were obvious advances in the theoretic foundation and the clinical application in treatment of the degenerative lumbar disorders with the dynamic stabilization devices, especially with the nonfusion dynamic stabilization devices. Conclusion The effectiveness of the dynamic stabilization devices have attracted more and more biomedical researchers, especially the posterior dynamic stabilization device, which has provided a new approach to treatment of the degenerative lumbar disorders.