BACKGROUND: At present, more and more scholars pay attention to the influence of spine and pelvis sagittal balance on the quality of life of patients. Postoperative changes in spine imaging parameters fol owing corrective osteotomy for lumbar degenerative kyphosis have not been reported. OBJECTIVE: To evaluate postoperative changes in sagittal balance fol owing corrective osteotomy for lumbar degenerative kyphosis. METHODS: We retrospectively analyzed 35 consecutive lumbar degenerative kyphosis patients treated with posterior osteotomy fixation in the First Affiliated Hospital of Xinjiang Medical University from February 2012 to December 2014. Imaging parameters were measured before fixation, immediately after fixation and during final fol ow-up. RESULTS AND CONCLUSION: (1) There were significant differences between preoperative and postoperative parameters except for pelvic incidence angle (P < 0.05). (2) There were significant differences between postoperative and last fol ow-up parameters except for Cobb angle, pelvic incidence angle, thoracic kyphosis angle and the thoracolumbar kyphosis (P < 0.05). (3) Pelvic tilt angle was negatively correlated with lumbar lordosis after fixation (r=-0.610, P < 0.001). Thoracic kyphosis was positively correlated with lumbar lordosis (r=0.598, P < 0.001). (4) Results suggested that lumbar sagittal contour can be significantly improved by corrective osteotomy for lumbar degenerative kyphosis. Simultaneously, reciprocal changes in the adjacent areas such as thoracic spine and pelvis occur to adapt to the new sagittal balance.

Objective:To evaluated the indications, methods, outcomes and prognosis of surgical treatment for post-traumatic epiphyseolisthesis at odontoid process in children.Methods:Retrospective analysis was performed on 5 cases of children with delayed epiphyseolisthesis of odontoid process in our institution from July 2009 to October 2016, including 1 male and 4 females. Initial surgery age were at1.7~5.4 years old, averaged (39.6±19.4) months and were 0.67-8 months, averaged (87.0±95.1) days. Disease duration ranged from 23 days to 8 months, with an average of 88 days. X-ray, CT and MRI examinations of the occipital-cervical area were taken to evaluate the type of the fracture and the severity of spinal cord compression. Children were treated with anterior loosening combined with posterior fixation fusion or posterior loosening reduction and internal fixation respectively.The function of spinal cord was evaluated by Frankel scale at pre- and post- operation. During the follow-up, X-ray and CT were performed to assess the fusion condition of the grafted bone.Results:The duration of operation was ranged from 75-145 months, with an average of (101.0±20.7) months; Blood loss ranged from 50-100 ml, with an average of (70.0±21.2) ml; follow-up duration ranged from 6 to 48 months, with an average of (23.5±17.6) months. Two cases preoperatively evaluated as Frankel C and D recovered to postoperative Frankel E. Among the five cases, two received satisfactory reduction, two cases received incomplete reduction, and one experienced failure reduction. The epiphyseolisthesis and bone grafted sites achieved solid fusion at 6-15 months after surgery, with an average of (9.5±3.4) months. The physiological curvature of cervical remained well without bone resorption, nonunion, pseudoarthrosis, as well as screw loosening or broken. Internal fixation of 2 cases were removed.Conclusion:Children with post-traumatic epiphyseolisthesis at odontoid process are not common in clinical practice. The detailed diagnosis of medical history, physical examination and comprehensive imaging evaluation. The posterior approach technique of C1-2 was feasible and effective, which could obtain decompression, reconstruction andstability all together.

Objective:To evaluate the long-term outcomes of posterior release, reduction, fixation, and fusion for irreducible atlantoaxial dislocation (AAD).Methods:Between January 2005 and June 2016, a total of 31 patients with irreducible AAD who had received posterior approach surgery were included. Among them, there were 13 males and 18 females, the average age was 39.1±13.5 years (range 9-72 years). The clinical data of the eligible individuals were collected and analyzed. Neck disability index (NDI) and Japanese Orthopaedic Association (JOA) scores were recorded to evaluate the recovery of neck and neurological functions. The atlantodental interval (ADI), clivus-canal angle (CCA), and cervico-medullary angle (CMA) were measured to evaluate the reduction of AAD. C 0-C 2 angle and C 2-C 7 angle were measured to evaluate the recovery of cervical alignment. For individuals with basilar invagination, the distances from the tip of odontoid process to Chamberlain line and Wackenheim line were measured to assess the reduction in the vertical direction. The duration of bony fusion and complications were also analyzed. Results:The mean follow-up period was 82.7±26.4 months (range 61-170 months). In terms of functional scores, the NDI dropped from 43.41%±11.60% before surgery to 12.19%±6.97% at the six months follow-up, and 9.45%±7.51% at the last follow-up ( F=89.56, P<0.001). The JOA increased from 9.48±2.41 points before surgery to 14.71±1.42 points at the six months follow-up, and 14.97±1.47 points at the last follow-up ( F=52.89, P<0.001). Regarding the horizontal and vertical dislocations, the ADI decreased from 9.16±2.32 mm before surgery to 1.39±1.04 mm at the six months follow-up, and 1.29±1.08 mm at the last follow-up ( F=189.61, P<0.001). The distance from the tip of odontoid process to Chamberlain line decreased from 11.15±4.35 mm before surgery to 2.03±2.83 mm at the six months follow-up, and 2.15±3.02 mm at the last follow-up ( F=37.58, P<0.001). The distance from the tip of odontoid process to Wackenheim line reduced from 6.81±2.57 mm before surgery to -2.23±1.58 mm at the six months follow-up, and -2.27±1.58 mm at the last follow-up ( F=122.16, P<0.001). For the amelioration of the compression on medulla and spinal cord, the CCA increased from 113.68°±12.67° before surgery to 143.39°±7.38° at the six months follow-up, and 142.39°±7.13° at the last follow-up ( F=67.13, P<0.001). The CMA increased from 115.71°±13.69° before operation to 145.58°±10.78° at the last follow-up ( F=41.44, P<0.001). Regarding the curvature of the cervical spine, the C 0-C 2 angle recovered from 1.94°±15.82° before surgery to 14.84°±6.45° at the last follow-up ( F=11.97, P<0.001), and the C 2-C 7 angle ameliorated from 27.26°±8.49° before operation to 19.26°±5.44° at the last follow-up ( F=11.13, P<0.001). Bony fusion was achieved in all cases, the fusion time was 9.71±2.55 months (range 5-15 months). A total of five complications occurred in the cases (two cerebrospinal fluid leakages, one deep infection, one transient neurologic deficit, and one dysphagia). They were all cured with corresponding treatments. In the last follow-up, none of the cases developed failure of internal fixation or re-dislocation. Conclusion:Posterior approach release, reduction, fixation and fusion technique is a safe and efficient surgical strategy with favorable long-term follow-up outcomes for irreducible AAD.