Objective The purpose of the retrospective study was to introduce a treatment option for atypical Hangman fractures (AHF) based on a new classification.Methods Sixty-seven patients with Hangman fractures were treated with a comprehensive treatment strategy.Firstly,Hangman fractures were classified as typical or atypical (AHF) lesions using computed tomography scans of the cervical spine.Secondly,AHF was divided into 1 of 4 types (type A1,A2,B1,and B2) devised by us to clarify the feature of injury.Thirdly,the injury status of disco-ligamentous complex (intact/indeterminate/ruptured) was evaluated using magnetic resonance imaging.If it was a stable lesion,conservative treatment was recommended.If not surgical treatment using anterior or/and posterior stabilization and fusion at C2-C3 level was used.Results Fifty-one patients were identified with AHF.According to our classification,thirty patients were classified as type A1,14 cases as typeA2,5 cases as type B1,and 2 cases as type B2 lesions.Thirteen AHF without C2-C3 instability (12 as type A1 and 1 as type B1) were treated with non-operative treatment,and 38 AHF with C2-C3 instability (18 as type A1,14 as type A2,4 as type B1,and 2 as type B2) were treated with operative treatment.Three patients (all with type A1 lesions) with slightly displacement of C2-3 underwent isolated direct screw osteosynthesis.The remaining 35 underwent posterior stabilization and fusion at C2-C3 level:24 patients with posterior approach with C2 lag screws and C3 non-lag screws fixation and fusion (11 as type A1,10 as type A2,2 as type B1,and 1 as type B2);3 patients with posterior approach with C1 and C3 screw-rod fixation and fusion (1 as type A1 and 1 as type B1);7 with anterior approach by C2-3 discectomy and fusion (3 as type A1 and 4 as type A2);and 2 with anterior and posterior approach (1 as type B1 and 1 as type B2).The average follow-up period was 26 months (range,12-86 months).Neck pain improved significantly at 3-month follow-up,and neurologic status improved at least 1 grade in 12 patients with neurologic deficits at final follow-up.Radiological evaluation showed bony fusion in all patients at 12-month follow-up.Radiological evaluation showed that all 13 AHF without C2-C3 instability treated with non-operative treatment gained fractures fusion at 3-6 month follow-up.Posterior approaches with C1 or C2 and C3 screw-rod fixation and fusion were found to obtain a better alignment of C2-C3 and satisfactory fusion of C2 pedicle factures than anterior approach.Conclusion The treatment option for AHF based on a new classification is helpful in managing such fractures,resulting in good clinical and radiological outcomes.C2 lag screws with or without C3 pedicle screws fixation via posterior approach may not only reduce fractures but also obtain alignment of C2-C3 effectively.

BACKGROUNDChordomas of the upper cervical spine are rare and present unique surgical challenge. This study aimed to describe the clinical characteristics and surgical management of patients with chordomas of the upper cervical spine.

METHODSTwenty-one patients with chordomas of the upper cervical spine who were treated in Peking University Third Hospital from January 1999 to October 2012 were retrospectively analyzed. Survival was calculated by the Kaplan-Meier method and was compared between groups using the log-rank test.

RESULTSThe postoperative diagnosis was classical chordoma in 20 cases and chondroid chordoma in one case. The mean operative time was 9.5 hours (range 6-17 hours), and the mean blood loss was 2 812 ml (range 700-4 800 ml). There were two postoperative deaths. Unilateral vertebral artery ligation was performed in six patients, cervical nerve roots were cut in six patients, and the external branch of the superior laryngeal nerve was repaired after being cut in one case. Two patients developed postoperative velopharyngeal incompetence, and loosening of the occipitocervical screws was observed in one patient. The recurrence rate was 66.7% (10/15) after a mean follow-up period of 46.8 months (range 14-150 months). The 5- and 10- year overall survival rates were (39.8±13.1)% and (31.9±12.7)%, respectively. There was a significant difference in survival rate between patients who underwent surgery and those who did not.

CONCLUSIONIn spite of the high rates of recurrence and complications after surgical treatment of chordomas of the upper cervical spine, intralesional resection combined with adjuvant radiotherapy remains the optimal treatment to prolong survival.

Adult ; Aged ; Cervical Vertebrae ; pathology ; surgery ; Chordoma ; diagnosis ; surgery ; Female ; Humans ; Male ; Middle Aged ; Neoplasm Recurrence, Local ; diagnosis ; surgery ; Retrospective Studies ; Spinal Neoplasms ; pathology ; surgery ; Treatment Outcome

BACKGROUNDThe treatment strategies for multilevel thoracic ossification of the posterior longitudinal ligaments (T-OPLL) were rarely reported. The aim of this study was to investigate the clinical outcomes and complications of circumferential decompression for multilevel T-OPLL and compare two different methods in the management of the OPLL (resection or floating).

METHODSData of sequentially treated patients who received surgical treatment for thoracic spinal stenosis caused by multilevel T-OPLL from January 2005 to February 2012 were retrospectively reviewed. Based on the surgical approaches applied, the patients were divided into two groups. Group A consisted the patients who received posterior decompression and group B consisted the patients who received circumferential decompression via the posterior approach. Group B was further divided into two subgroups: subgroup 1 (the resection group) where the OPLL was completely resected and subgroup 2 (the floating group) where the OPLL was floated.

RESULTSA total of 49 patients were included in the study. Fourteen patients with single posterior decompression were included in group A and 35 patients who received circumferential decompression were included in group B. In group B, 29 patients had complete resection of the ossified posterior longitudinal ligaments, while the other six underwent a flotation procedure. The follow-up data were available in 39 patients. Mean JOA scores improved from 5.4 ± 1.8 to 7.5 ± 2.8 in group A and from 3.7 ± 1.8 to 7.9 ± 2.4 in group B. The main complications included cerebrospinal fluid (CSF) leakage and postoperative neurologic deterioration (ND). Twenty-three of the 25 cases with postoperative CSF leakage achieved a complete recovery at the last follow-up and 12 of the 15 cases with ND achieved some neurological improvement at the last follow-up.

CONCLUSIONSCircumferential decompression via the posterior approach is an effective surgical method for thoracic spinal stenosis caused by multilevel OPLL of the thoracic spine. Patients who receive complete resection of the ossified posterior longitudinal ligaments may have better recovery rate than the "floating" group.

Adult ; Decompression, Surgical ; methods ; Female ; Humans ; Longitudinal Ligaments ; pathology ; surgery ; Male ; Middle Aged ; Ossification of Posterior Longitudinal Ligament ; surgery ; Retrospective Studies ; Thoracic Vertebrae ; surgery ; Treatment Outcome

Objective To investigate surgical strategy and outcome for cervical metastasis in different anatomical segments.Methods Data of 31 patients,who had undergone surgical treatment for cervical metastasis from 2001 to 2009,were retrospectively analyzed.Two anatomical regions were defined:upper cervical spine (C1 and C2)and subaxial cervical spine plus cervicothoracic junction (C3-T1).VAS score,Frankel grade,Tomita score and Karnofsky performance scale were used to evaluate pain,neurological status,expected survival time and general health.The improvement of symptoms,survival time and characteristics of surgical strategies for different anatomical regions were analyzed.Results Twenty-four patients were followed up successfully.An effective recovery in neck pain and quality of life was found after operation.The median survival time was 45.0 months.In upper cervical spine group,the surgical strategies included posterior occipitocervical fixation combined with 125I seed brachytherapy and other surgical methods,and the median survival time 48.0 months) of patients who underwent 125I seed brachytherapy was longer than that 22.0 of patients treated with other surgical methods.In C3-T1 metastasis group,patients who underwent combined anterior-posterior approach total spondylectomy had a longer survival time than those treated with anterior corpectomy.Conclusion Surgical treatment can effectively relief neck pain,maintain or improve neurological function and improve quality of life.Doctors should choose different surgical strategies according to anatomical region of cervical metastasis.For upper cervical spine,the main purpose of surgery is to stabilize the cervical spine; the posterior occipitocervical fixation is usually chosen,and the 125I seed brachytherapy is useful in local control of metastasis.For subaxial cervical spine and cervicothoracic junction,the anterior corpectomy is usually chosen,and a combined anterior-posterior approach total spondylectomy can be used for patients with corresponding conditions.

ObjectiveTo explore the bone anabolic effects after a single local injection of simvastatin into femoral cavities of osteoporotic rats.MethodsThirty-six female SD rats(3 months old,body weight 250-300 g) were ovariectomized(OVX) and low-calcium-diet fed for 3 months,OVX rats were randomized into 3 groups(n=12).Left femurs of group A,B and C were injected with 0,5 and 10 mg simvastatin,respectively.Half of the rats in each group were randomly euthanized separately 1 and 5 months after simvastatin injection.Left femurs were taken out for bone mineral density (BMD) assessment with dual energy X-ray absorptiometry,bone histomorphometic changes were analysized by Micro-CT,and two kinds of biomechanical tests were used to evaluate the osteogenic effects.ResultsOne and five months after injection,BMD in mid-diaphysis significantly increased in simvastatin-injected groups compared to the control group.For Micro-CT analysis,significant increase in total bone volume/total tissue volume,cortical wall thickness,trabecular thickness,trabecular number,and a significant decrease in trabecular spacing were observed in simvastatin-injected groups compared to the control group.For both biomechanics (the three-pointbreaking test of condyles and axial compressive testing of proximal femur),the values were significantly higher in simvastatin-injected groups than the control group.ConclusionLocal simvastatin treatment showed a positive effect on improving mechanical strength,structure of osteopenic femurs and BMD.Our findings may provide a new strategy for the prevention and treatment of osteoporosis,especially for osteoporotic fractures.

Objective To sum up the clinical experience in diagnosis and treatment of spinal primitive neuroectodermal tumor (PNET). Methods Thirteen patients with spinal PNET were included in the study from 1999 to 2009. There were 8 males and 5 females with the mean age of 26.9 years. The lesions involved the cervical spine in 6 cases, the thoracic segment in 1 case, the lumbar segment in 5 cases and the sacrum in 1 case. The diagnosis of PNETs was made in nine patients by postoperative pathological examination. Among them, 6 patients received a preoperative CT-guided percutaneous biopsy. The other four patients were diagnosed only by CT-guided percutaneous biopsy. Osteolytic bony lesions and obvious neurological deficit were found in ten patients, while the other 3 had complained of local pain only. Nine patients had received operation followed by chemotherapy and radiotherapy. The other 4 underwent only chemotherapy and radiotherapy. The changes of symptoms and time of survival were recorded. Results Eleven patients were followed up with the mean of 21.8 months. The back pain in 7 patients who underwent operation relieved one month after the operation. The bladder and bowel function returned to normal condition after the operation. Among them, four patients died postoperatively. The mean survival time was 11.3 months. The otherthree patients survived with an average of 36 months. Three patients who had only received chemotherapy and radiotherapy died with an average of 7 months, while the other patient survived for 5 months. Conclusion The diagnoses of spine PNET mainly depend on pathological examination. Percutaneous CT-guided biopsy is a reliable method to confirm diagnose of tumor before surgery. The mortality rate of spinal PNET which is a highly malignant tumor is high. Operation can relieve clinical symptoms and improve patients' life quality, but not prolong the survive time.

Objective To summarize the clinical outcome of single posterior fixation and fusion in treatment of cervical spinal fracture combined with ankylosing spondylitis.Methods A total of 26 patients with cervical spinal fracture combined with ankylosing spondylitis admitted for surgical treatment from June 2003 to June 2008 were reviewed to analyze parameters including injury mechanism,injury severity,treatment course,operation records,postoperative follow-up and rehabilitation and evaluate neurologic recovery and fracture healing by using American Spinal Injury Association(ASIA)classification.Results A single posterior surgical procedure was performed in six patients,of whom the spinal cord function were rated at grade A in two patients,at grade B in one,at grade C in two and at grade D in one according to ASIA classification criteria.All patients were treated with posterior reduction and lateral mass fixation plus fusion.Two patients at grade ASIA A died of respiratory failure at 2 and 3 months respectively after operation.The other four patients were followed up for 12-54 months(mean 37 months),which showed solid fusion at average 3.8 months after operation and significant improvement of neural function.One patient with aggravated symptoms of spinal epidural hematoma at grade ASIA B was improved to grade D postoperatively.The patients at grades C and D recovered to normal.Hyponatremia occurred in two patients at grade ASIA A.There was no instrumentation related complications in all patients.Conclusions For cervical spinal fractures combined with ankylosing spondylitis without bone defect at fracture end,lateral mass fixation and autologous bone graft through a single posterior approach can attain stable fracture healing after sound reduction.

Objective To evaluate retrospectively the causative factors and corresponding surgical treatments of cervical spinal cord injuries without fracture or dislocation. Methods 29 cases of cervical spinal cord injury without fracture or dislocation were studied to analyze their imaging manifestation, features and causative factors of the injury, and pathological elements. Different surgical operations were performed accordingly, and their short-term outcomes were evaluated. Results The analysis indicated that there were chiefly 3 groups of causative factors. About 24% of the patients were typical cervical disc protrusion or prolapse, about 52% of them suffered from obvious decrease or even disappearance of the storing space of spinal canal, and about 24% suffered from decrease of the storing space of spinal canal combined with segmental instability among the vertebras, or with cervical disc prolapse. The postoperative short follow-ups (a mean period of 8.5 months) for the 29 surgical treatments showed that their spinal cord functions had been improved significantly, with the recovery rate being 52.8% by Japanese Orthopaedic Association (JOA) scoring. Conclusions Despite some common features, the causative factors for the cervical spinal cord injury without fracture or dislocation are quite different. Consequently, in order to achieve satisfactory outcomes, corresponding surgical operations with different approaches should be performed, and proper internal fixation should be applied according to the specific indications.

Objective: To observe the effect of simvastatin on osteoblastic cell differentiation of bone marrow stromal cells in vitro, and to elucidate the mechanisms of anabolic effect of simvastatin on bone formation. Methods: Bone marrow stromal cells from femur and tibia of adult female BALB C mice were cultured in vitro , after being treated with different concentrations of simvastatin for 72 h, changes of mRNA level of osteocalcin (OCN) were detected by RT PCR, change of OCN, and osteopontin (OPN) expression were examined by Western blot, and the changes of cellular alkaline phosphatase activity (ALP) were examined by histochemistry and enzymologic measurement. Results: After bone marrow stromal cells were treated with different concentration of simvastatin for 72 h, level of OCN mRNA increased, and expression of OCN and OPN also increased in a concentration dependent manner, and cellular ALP activity significantly increased in a concentration dependent manner. Conclusion: Simvastatin can stimulate osteoblastic differentiation,and improve cellular ALPase activity with high expression of osteocalcin and osteopontin in vitro. These may be parts of the mechanism of anabolic effect of simvastatin on bone formation.

OBJECTIVETo construct the adenoviral vector bringing hVEGF(121) cDNA for evaluation of the possibility of VEGF gene therapy in ischemic bone disease.

METHODSHuman vascular endothelial growth factor (hVEGF(121)) cDNA obtained from the plasmid pCDI/VEGF(121) was cloned into plasmid pshuttle and further cloned to Adeno-X Viral DNA. The recombinant adenoviral plasmid was identified and then transferred to the adenoviral packaging cell HEK293 by lipofectamine mediated gene transfer method to pack the virus. After titilating the virus, the mouse bone marrow stromal cells (MSC) were transfected by the adenovirus and the expression of VEGF gene was detected.

RESULTSThe recombinant Adeno-VEGF(121) was correctly constructed and confirmed by restriction endonuclease analysis and DNA sequencing analysis. After MSCs were tranfected by the virus, RT-PCR showed that hVEGF(121) mRNA was transcripted from the hVEGF(121) gene. Western blot and immune histochemistry showed VEGF(121) protein was expressed in transgene MSCs.

CONCLUSIONThe recombinant adenoviral vector bringing hVEGF(121) cDNA was successfully constructed and the transgene MSC expressed hVEGF gene in vitro, it provided the further foundation of VEGF gene therapy for bone ischemic diseases.

Adenoviridae ; genetics ; Blotting, Western ; Cells, Cultured ; DNA, Complementary ; genetics ; Endothelial Growth Factors ; genetics ; metabolism ; Gene Expression ; Gene Transfer Techniques ; Genetic Vectors ; genetics ; Humans ; Immunohistochemistry ; Lymphokines ; genetics ; metabolism ; Vascular Endothelial Growth Factor A ; Vascular Endothelial Growth Factors