ObjectiveTo evaluate the effectivity and safety of posterior osteotomy for thoracolumbar stress fracture in ankylosing spondylitis (AS) through the gap of a pathological fracture.MethodsBetween April 2012 and August 2015, 8 patients with AS combined with thoracolumbar stress fracture were treated with posterior osteotomy through the gap of a pathological fracture to correct the kyphosis. There were 7 males and 1 female, with an average age of 51 years (range, 37-74 years). The history of AS was 1-40 years (mean, 21.7 years) and disease duration of stress fracture was 2-60 months (mean, 18.5 months). The segmental lesions included T8, 9 in 1 case, T10, 11 in 2 cases, T11 in 2 cases, T12, L1 in 1 case, L1, 2 in 1 case, and L2, 3 in 1 case. The nerve function before operation according to Frankel grading was grade D in 3 cases and grade E in 5 cases. The pre- and post-operative X-ray films, CT three-dimensional reconstruction, and MRI were collected to measure the global kyphosis (GK), local kyphosis (LK), angle of the fusion levels (AFL), pelvic incidence (PI), pelvic tilt (PT), and sagittal vertical axis (SVA). Visual analogue scale (VAS) score was used to assess the back pain intensity.ResultsThe operation time was 210-320 minutes (mean, 267 minutes), and the intraoperative blood loss was 400-2 000 mL (mean, 963 mL). Cerebrospinal fluid leakage was found in 3 patients, and the wound healed by removal of drainage tube and suturing drainage outlet after 5-7 days of operation. The wounds of the rest patients healed by first intention. Lower extremity numbness occurred in 1 case and recovered after 1 month of postoperative administration of oral mecobalamin. All the patients were followed up 20-43 months (mean, 28.4 months). No internal fixator loosening, fracture, and other complications occurred. All the fractures healed with the healing time of 3-12 months (mean, 6.8 months). At 3 months after operation, 3 cases with spinal cord injury of preoperative Frankel grade D recovered to grade E. The GK, LK, AFL, PI, PT, SVA, and VAS scores at 1 week after operation and at last follow-up were significantly improved when compared with preoperative ones (P<0.05). Except for VAS score at last follow-up was significantly improved when compared with that at 1 week after operation (P<0.05), there was no significant difference in the other indexes between at 1 week after operation and at last follow-up (P>0.05).ConclusionPosterior osteotomy through the gap of a pathological fracture is a safe and effective surgical procedure for kyphosis correction and relief of back pain in AS patients combined with thoracolumbar stress fracture. Successful bony fusion and good clinical outcomes can also be achieved by this surgical procedure.
Objective To evaluate the safety and efficacy of the operation performed under the video-assisted thoracoscope to release the anterior part of the spine of the patient with severe adolescent idiopathic scoliosis (AIS). Methods From April 2004 to July 2006, 24 patients with AIS (Illness course, 1.5-9 years; Lenke Ⅰ in 17 patients, Lenke Ⅱ in 7; right scoliosis in 22, left scoliosis in 2), among whom there were 9 males and 15 females, with an average age of 14.7 years (range, 11-21 years) at the time of the operation. Before operation, the thoracic vertebral Cobb anger at the coronal plane was averaged 78.3°(range, 65-125°). All the patients had normal muscle strength and muscle tension in their lower limbs, but 5 of the patients had a decrease of the superficial sensation in their lower limbs. All the patients had a moderately or severely decreased lung reserve function. Under general anesthesia, the patient was placed in the lateral position to set up a work channel for thoracoscopy. The releasing of the thoracic intervertebral space and the confluence of the bone grafts were performed. During Stage Ⅰ or Stage Ⅱ, the orthopedic procedures for the posterior part of the scoliosis spine, the internal fixation, and the confluence ofthe bone grafts were completed. ResultsAll the patients survived the periodof perioperation. During operation, there was a hemorrhage of 50-200 ml, averaged 100 ml, with a postoperative thoracic closely-drained fluid of 100-150 ml. The incision was healed by the first intention. Each patient underwent the releaseof 4-6 intervertebral spaces, with an average of 5.5 spaces released. The average coronal Cobb angle was 45.6°(range, 25-75°). The physiological curvatureat the sagittal plane was normal, with an improved shape of the spine. The follow-up for 3-18 months averaged 9.3 months revealed that the bilateral pulmonary markings were clear, with confluence of the orthopedic segment of the spine. The patients could live and work normally, and had a significantly-improved psychological condition and an active social participation because of their improved appearance. Conclusion The releasing of the anterior part of the spine under the video-assisted thoracoscope can effectively release the adolescent idiopathic scoliosis and improve the flexibility of the spine, with a smaller degree of the surgical wound and a faster and clearer exposure of the spinal column during operation.
In order to find an ideal biological material to prevent peridural adhesion following laminectomy, 30 rabbits were used as animal model, in each of which 2 defects with a size of 1 cm x 0.5 cm were made following laminectomy of L3, L5 spine. One of the defects was covered extradurally with chitosan, gelatin foam or PLA membrane respectively, while the other defect was exposed as control. All of these animals were sacrificed on the 2nd, 4th, 6th, 8th and 10th week after operation, and the extradural fibrosis and adhesion of every animal were evaluated by gross observation and histological examinations. It was revealed that in the chitosan and PLA membrane groups, the extradural tissue was smooth without thickening and there was no fibrous proliferation or adhesion in the epidural cavity, and that in the chitosan group, the growth of fibroblast was restrained but the growth of the epithelial cells was promoted significantly, thus, wound healing was rapid. In the control group and gelatin foam group, obvious extradural fibrosis and adhesion were observed and the extradural space had almost disappeared. Therefore, it was concluded that the biodegradable PLA membrane and chitosan were both an ideal material in the prevention of postoperative epidural adhesion.
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 clinical effect of polylactic acid membrane in prevention of epidural scar and adhesion. Methods From July 1998 to April 2000, 62 patients with lumbar disc herniation were randomly assigned into two groups. All were treated surgically with discectomy by fenestration or laminectomy.One group were placed with a thin of polylactic acid membrane covering the interlaminar space(n=32). The thickness of the film was 0.1mm. The other group was blank control(n=30). After 2 weeks of operation, we observed the local and systemic reactions. After 6 months clinical symptoms were revaluated and the degrees of epidural scar and adhesion were determined by CT scans. Results After 2 weeks, we found no adverse systemic reactions in all patients. Wound healing was excellent. No abnormalities of hepatic and renal functions as well as blood for routine were found. Temperature after operation was normal. After 6 months, the curative effects were as follows in experimental group and in control group: excellent in 27 patients and in 24 patients, good in 4 patients and in 4 patients, fair in 1 patient and in 1 patient, and poor in 0 patient and in 1 patient, respectively. There are no significant difference between two groups. The CT scans showed no adhesion between the epidural scar and the dural sac in all patients of experimental group. There existed various extents of adhesion in control group. Conclusion The results demonstrate that the polylactic acidmembrane can effectively prevent the epidural scar adhesion with a good biocompatibility and no toxity. Its clinical application was promising.
Polyetheretherketone is one of the most commonly used materials for the production of orthopaedic implants, but the osseointegration capacity of polyetheretherketone is poor because of its bioinert surface, which greatly limits its clinical application. In recent years, scholars have carried out a lot of research on the modification of polyetheretherketone materials in order to improve its osseointegration capacity. At present, the modification of polyetheretherketone is mainly divided into surface modification and blend modification. Therefore, this paper summarizes the research progress of polyetheretherketone material modification technology and its influence on osseointegration from two aspects of surface modification and blend modification for polyetheretherketone materials used in the field of bone repair, so as to provide a reference for the improvement and transformation of polyetheretherketone materials for bone repair in the future.
ObjectiveTo completely establish a three-dimensional (3D) simulation model of degenerative lumbar scoliosis (DLS) with the whole lumbar segments, then to analyze the biomechanical changes of the scoliosis segments by finite element analysis.MethodsA case of DLS patient was selected with L1-5 segments of CT scanning data, which was imported into MIMICS 15, SolidWorks, Hyper-Mesh software to establish a 3D simulation model, and ANSYS 15 was used to analyze the model. At the same time, different material properties and boundary loading conditions were assigned to various structures to simulate the actual human body conditions.ResultsThe 3D model built a total of 856 154 units and 232 850 nodes, including the reconstruction of fine vertebral bodies, intervertebral disc tissue, structure of various ligaments and joint cartilages. Under the load and torque, the range of whole lumbar segments was decreased, in the stress distribution on the four discs: the L2/3 intervertebral disc stress value (3.320 MPa) > L 4/5 intervertebral disc stress value (0.783 MPa) > L 3/4 intervertebral disc stress value (0.551 MPa) > L 1/2 intervertebral disc stress value (0.462 MPa). The stress distribution of the vertebral body showed that, L5 vertebral stress (34.0 MPa) > L 4 (33.6 MPa) >L 3 (30.0 MPa) > L 1 (23.3 MPa) > L 2 (22.4 MPa).ConclusionThe range of motion of the six degrees of freedom of the lumbar spine in DLS is decreased, the local stress distribution of the lumbar spine is abnormal, and the abnormal stress changes of the apical vertebral body and the top intervertebral disc may be the biomechanical basis for the occurrence or progression of DLS.
In the surgical treatment of adolescent idiopathic scoliosis (AIS), the posterior pedicle screw system has a better orthopaedic effect than the traditional internal fixation orthopaedic system, and has been widely used in the orthopaedic surgery of AIS. Although the vast majority of patients respond well to surgical treatment, complications can still occur. Aortic injury is one of the rare complications, but it can lead to catastrophic consequences. Spinal surgeons must be fully familiar with the knowledge of aortic injury and the appropriate management and management methods. This article reviews the complication of aortic injury caused by surgical treatment of AIS.