Risk factors for pulmonary cement embolism associated with percutaneous vertebral augmentation: A systematic review and meta-analysis.

BACKGROUND: Pulmonary cement embolism (PCE) was a rare but fatal complication for percutaneous vertebral augmentation (PVA). Thus we did a systematic review and meta-analysis of cohort studies to investigate the risk factors for PCE after PVA. METHODS: We systematically searched PubMed, EMBASE, Cochrane library, Google Scholar, web of science, and ClinicalTrial.gov from the establishment of the database to September 2021. All eligible studies assessing the risk factors for PCE after PVA were incorporated. Dichotomous data was calculated by risk difference (RD) from Mantel-Haenszel method (M - H method); continuous data was analyzed by mean difference (MD) from Inverse-Variance method (I-V method). All variables were taken as measure of effect by fixed effect model. Heterogeneity, sensitivity, and publication bias analyses were also performed. RESULTS: This study totally included 13 studies. According to the Newcastle-Ottawa Scale (NOS), 7 studies were considered as low quality, with NOS< 6. The others were of relatively high quality, with NOS≥6. 144/6251 patients (2.3%) had PCE after PVA. percutaneous vertebroplasty (PVP) (RD = 0.02, 95%CI: [0.01, 0.04], Z = 3.70, P < 0.01), thoracic vertebra (RD = 0.03, 95%CI: [0.01, 0.05], Z = 3.53, P < 0.01), higher cement volume injected per level (MD = 0.23, 95%CI: [0.05, 0.42], Z = 2.44, P = 0.01), more than three vertebrae treated per session (MD = -0.05, 95%CI: [-0.08, -0.02], Z = 3.65, P < 0.01), venous cement leakage (RD = 0.07, 95%CI: [0.03, 0.11], Z = 3.79, P < 0.01) were more likely to cause PCE. CONCLUSION: This study showed that risk factors for PCE included PVP, thoracic vertebra, higher cement volume injected per level, more than three vertebrae treated per session, venous cement leakage. As a serious complication, PCE should be paid attention and avoided.

The Comparative Influence of 2 and 4 Weeks Preoperative Antituberculosis Treatment on Spinal Tuberculosis Surgery: A Multicenter, Prospective, Randomized Clinical Trial.

INTRODUCTION: A trade-off between successful surgery and minimizing the operation delay for patients with spinal tuberculosis (TB) is a major consideration to determine the duration of preoperational anti-TB treatment (AAT). In this study, 2 and 4 weeks preoperative AAT durations were compared for their influence on the operation outcomes. METHOD: A multicenter, prospective, randomized trial was conducted in four hospitals in China. New patients with spinal TB were recruited and randomly allocated to two groups (2 or 4 weeks' preoperative treatment) and administered the standardized first-line anti-TB drugs. The symptom changing and indicators reflecting recovery and side effects of the treatment were monitored. Patient was followed up for another 18 months after completion of treatment. RESULTS: In total, 150 eligible patients were enrolled between June 2014 and December 2016, and 13 patients were excluded after the enrollment. The remaining 137 participants were randomly allocated to the 2-week group (n = 68) or the 4-week group (n = 69). These two groups acquired similar surgical outcomes, considering wound healing rate within 3 months after the operation (94.20%, 65/69 vs 89.71%, 61/68; P = 0.333) and bony fusion rate within 6 months (98.46%, 64/65 vs 95.45%, 63/66; P = 0.317). However, the culture positive rate of pus collected during operation in the 4-week group (41.94%) was significantly lower than that of the 2-week group (60.94%, P = 0.033). No reoccurrence of disease was observed in either group during the 18-month follow-up period. CONCLUSION: Patients with spinal TB administered 2 or 4 weeks of preoperative anti-TB treatment acquired similar surgical outcomes. However, patients who underwent the operation sooner suffered 2 weeks less agony from the disease.

Anatomic relationship between the cervical sympathetic trunk and cervical fascia and its application in the anterolateral cervical spine surgical approach.

OBJECTIVES: To understand the anatomical relationship between the cervical sympathetic trunk (CST) and the cervical fascia and to provide a more reliable method for avoiding CST injury during the anterolateral cervical spine surgical approach. METHODS: Forty-two formalin-fixed adult cadaver specimens were divided into two groups. In the first group, the distance from the inner edge of the bilateral CSTs to the medial border of the longus colli muscle (LCM) and the distance between the CST and the midline of the cervical vertebrae were measured from the middle of the C3 vertebra through the C7 vertebra. The positional relationship between the CST and the superficial layer of the prevertebral fascia (alar fascia) was observed. In the second group, the carotid sheath and its contents were cut horizontally to observe the relationship between the CST and the carotid sheath. RESULTS: In the first group, the CST gradually converged medially and was closest to the medial border of the LCM at the level of the C7 vertebra. The distance from the CST to the vertebral midline was the smallest at the level of the C7 vertebra. In all specimens, the CST was closely adhered behind the alar fascia above the C7 vertebra and therefore could not be easily separated from the alar fascia by blunt dissection. In the second group, the CST in all specimens was tightly adhered behind the carotid sheath. CONCLUSION: The CST was tightly adhered to the alar fascia and could be naturally retracted with the alar fascia. Retracting the alar fascia can effectively protect the CST.

Does Rheumatoid Arthritis Affect the Infection and Complications Rates of Spinal Surgery? A Systematic Review and Meta-Analysis.

BACKGROUND: Rheumatoid arthritis (RA) is a chronic autoimmune disease that produces synovial membrane inflammation and causes progressive articular damage with function loss. Some controversy exists regarding whether RA is associated with infection and complications after spinal surgery. The present study aimed to determine the effect of RA on spinal surgery infection and complications. METHODS: A systematic literature search was performed in accordance with the PRISMA (preferred reporting items for systematic reviews and meta-analyses) guidelines. All studies that had compared patients who had undergone spinal surgery with and without RA were included in the analysis. RESULTS: We found significantly greater rates statistically of complications (odds ratio [OR], 1.43; 95% confidence interval [CI], 1.20-1.70; P < 0.05) and infections (OR, 1.69; 95% CI, 1.46-1.95, P < 0.05) in those with RA than in those without RA after spinal surgery. When registry data were excluded, the results suggested that the incidence of complications (OR, 2.24; 95% CI, 0.92-5.44; P = 0.08) and infections (OR, 1.76; 95% CI, 1.50-2.07; P < 0.05) was still greater for the RA group than for the non-RA group. CONCLUSION: When undergoing spinal surgery, patients with RA have a greater risk of operative complications and infection. Surgeons should be aware of these risks and appropriately plan spinal operation for patients with RA to reduce the risk of complications.

Clinical and radiological subsequent fractures after vertebral augmentation for treating osteoporotic vertebral compression fractures: a meta-analysis.

PURPOSE: This study aimed to identify all relevant randomized controlled trials (RCT) and prospective non-RCTs to further investigate whether percutaneous vertebral augmentation (PVA) was associated with clinical and radiological subsequent fractures on unoperated levels. METHODS: We systematically searched PubMed, EMBASE, Cochrane library, Google Scholar, web of science, and ClinicalTrial.gov from the establishment of the database to January 2020. All eligible studies comparing subsequent fractures after PVA with those after conservative treatment (CT) were incorporated. The pooled risk ratio (RR) with its 95% confidence intervals (95% CIs) was used. Heterogeneity, sensitivity, and publication bias analyses were performed. RESULTS: In all, 32 studies were included in the study: 82/512 patients (16.02%) and 58/433 patients (13.39%) had clinical subsequent fractures in the PVA group and CT group, respectively. No significant differences were observed between the two groups [RR = 1.22, 95% CI 0.70-2.12, P = 0.49]. Further, 175/837 patients (20.91%) in the PVA group and 160/828 patients (19.32%) in the CT group had radiological subsequent fractures. No significant difference was observed between groups [RR = 0.91, 95% CI 0.71-2.12, P = 1.16]. Further, no statistical difference was observed on subgroup analysis between RCTs and non-RCTs or PVP and PKP. CONCLUSION: Our systematic review revealed that subsequent fractures on unoperated levels were not associated with PVA, regardless of whether they were clinical or radiological subsequent fractures.

Salmonella enteritis spondylitis of thoracic spine: a case report and review of the literature.

BACKGROUND: Spondylitis is a very common back problem in orthopedics, but is rarely caused by Salmonella enteritidis. We herein reported an uncommon case of thoracic spondylitis caused by Salmonella enteritidis. CASE PRESENTATION: A 68-year-old man with high fever was diagnosed as salmonella septicemia initially. His condition was improved after antibacterial treatment. But the symptom of pyrexia was recurred after some days. He was then diagnosed with thoracic spondylitis caused by salmonella enteritidis. After that, he was put on strict antibiotic treatment, and underwent intervertebral lesion debridement, partial rib resection, intervertebral bone fusion and pedicle screw internal fixation. Subsequently, the patient had a significant relief in pain, temperature remained normal, and had no severe complications. CONCLUSIONS: Special attention should be paid to systemic pain and remain cautious to the occurrence of osteomyelitis in patients with Salmonella septicemia. Moreover, the treatment time for using sensitive antibiotics should be sufficient. Surgical treatment should be considered if strict conservative treatment is failed.

A new interspinous process distraction device BacFuse in the treatment of lumbar spinal stenosis with 5 years follow-up study.

To explore a suitable indication of interspinous process distraction device for lumbar spinal stenosis with BacFuse.Patients of lumbar spinal stenosis (LSS) who experienced interspinous process distraction device surgery with BacFuse from June 2014 to January 2015 in our institute were included. We classified LSS into central and lateral types, and then divided these into severe and moderate according to the degree of stenosis. Each type was divided into 2 groups. Patients in group A underwent distraction without bone decompression (stand-alone), while patients in group B underwent bone decompression combined with distraction. Follow-up was performed at 1 month, 3 months, 6 months, 2 years, and 5 years after surgery. Zurich Claudication Questionnaire (ZCQ) was recorded to assess the patient's postoperative condition at each follow-up.A total of 142 patients were available for follow up at each time interval. There was a significant difference between the preoperative and final follow-up ZCQ scores for every LSS type. In addition, there was no difference between group A and group B in the postoperative ZCQ scores with the exception of the lateral severe type. In the study, 22 of the 23 patients (95.65%) in the lateral moderate type were considered to have a satisfactory result in group B, with a similar result of 93.33% (14/15) in group A (P = .75). In the lateral severe type, the patient satisfaction rate was 65.22% (15/23) and 90.63% (29/32) in group A and group B (P = .02), respectively. In the central moderate type, the patient satisfaction rate was 81.82% (15/23) and 76.92% (10/13) in group A and group B (P = .77), respectively. Satisfaction rate for the follow-up results in the central severe type reached 57.14% (4/7) in group A, and 54.55% (6/11) in group B (P = .91). Moreover, no relationship was found between satisfaction and neurogenic intermittent claudication.The most suitable indication for BacFuse treatment was the lateral moderate type. For lateral severe patients, distraction combined with decompression is suggested for a higher satisfaction rate. Severe central spinal stenosis was shown to be a relative contraindication for BacFuse.

The effectiveness of a novel surgical approach for the treatment of congenital muscular torticollis.

The outcomes of surgical treatment for congenital muscular torticollis (CMT) are poor in many cases, primarily from surgeon's fear of damage to important blood vessels in the carotid sheath. The current research aimed to establish a novel, safer and more effective surgical approach for the treatment of CMT based on the anatomic relationship between the fascial sheath of the sternocleidomastoid muscle and the carotid sheath.A total of 12 formalin-fixed cadaveric specimens (including 9 males and 3 females with average age of 48.1 years at the time of death) were used to observe the anatomical integrity and the compactness of the sternocleidomastoid fascial sheath and its relationship with the carotid sheath. From January 2013 to December 2015, 22 patients with CMT were treated surgically, including 12 males and 10 females with an average age of 13 years (range: 6-28 years). All patients underwent surgical treatment using the novel approach designed by the author, that is, separation of the fascial sheath of the sternocleidomastoid and the carotid sheath was performed.The fascial sheath of the sternocleidomastoid muscle is easily isolated from the carotid sheath in all specimens. All procedures were successfully completed. The space between the fascial sheath of the sternocleidomastoid muscle and the carotid sheath can be accessed in all patients. Carotid sheath contracture was identified in 1 patient and divided successfully. The average follow-up period was 19 months (range: 5 to 43 months). No postoperative lateral band was noted in the neck in any of the patients. Satisfaction regarding cosmetic and functional outcomes was considered excellent in 13 patients, good in 7 patients, and fair in 2 patients.The fascial sheath of the sternocleidomastoid muscle is easily isolated from the carotid sheath. This anatomical feature is the basis of division of the sternocleidomastoid muscle and can improve the safety and effectiveness of surgical treatment for CMT in patients older than 6 years old.

Long-Term Outcome of Dynesys Dynamic Stabilization for Lumbar Spinal Stenosis.

BACKGROUND: Many clinical studies over the past decade have indicated positive outcomes for patients treated with Dynesys dynamic stabilization for lumbar degenerative disease. However, long-term outcomes of Dynesys for lumbar spinal stenosis are rarely reported. The aim of this study was to analyze the long-term clinical and radiologic outcomes for patients with lumbar spinal stenosis treated with Dynesys stabilization. METHODS: Thirty-eight patients with lumbar spinal stenosis were treated with Dynesys stabilization from July 2008 to March 2010. The minimal duration of follow-up was 72 months. The patients were divided into stenosis and spondylolisthesis groups according to degenerative spondylolisthesis. Clinical outcomes were evaluated using the Oswestry Disability Index (ODI) and visual analog scale (VAS). Radiographic evaluations included range of motion (ROM) and the disc heights of stabilized segments and the upper adjacent segments. We also evaluated the occurrence of radiographic and symptomatic adjacent segment degeneration (ASD). RESULTS: There were 23 patients in stenosis group and 15 patients in spondylolisthesis group. The ODI scores were significantly improved at the final follow-up evaluation, as compared to the baseline values (16.1 ± 5.7 vs. 57. 2 ± 14.2, t = 61.41, P < 0.01). The VAS scores for back and leg pain were significantly improved from 4.82 ± 0.89 and 4.04 ± 0.82 preoperatively to 0.93 ± 0.61 and 0.54 ± 0.51 postoperatively (t = 6.59, P < 0.01, and t = 5.91, P < 0.01, respectively). There were no differences between the two groups with respect to VAS and ODI scores. The ROM of stabilized segments decreased significantly from 7.8° ± 2.4° to 4.5° ± 1.5° (t = 7.18, P < 0.05), while the upper adjacent segments increased significantly from 8.3° ± 2.4° to 10.4° ± 2.4° (t = 2.87, P = 0.01). The change in disc height of stabilized segments was not significant (11.9 ± 2.1 preoperatively vs. 12.5 ± 1.5 postoperatively, t = 1.43, P = 0.15), whereas the decrease in disc height of the upper adjacent segments was significant (12.5 ± 2.0 preoperatively vs. 11.0 ± 1.7 postoperatively, t = 2.94, P = 0.01). The occurrence of radiographic and symptomatic ASD was 16% (6/38) and 3% (1/38), respectively. CONCLUSIONS: Decompression and Dynesys stabilization for lumbar stenosis with or without spondylolisthesis showed good long-term clinical and radiographic results. Lumbar stenosis with or without Grade I spondylolisthesis, particularly in patients <60 years of age with mild-to-moderate lumbar disc degeneration, would be one of the main indications for the Dynesys system.

Anatomic Relationship Between Right Recurrent Laryngeal Nerve and Cervical Fascia and Its Application Significance in Anterior Cervical Spine Surgical Approach.

STUDY DESIGN: An anatomic study of anterior cervical dissection of 42 embalmed cadavers. OBJECTIVE: The aim was to study the anatomic relationship between recurrent laryngeal nerve (RLN) and cervical fascia combined with the requirements in anterior cervical spine surgery (ACSS). SUMMARY OF BACKGROUND DATA: There has been no systematic research about how to avoid RLN injury in anterior cervical spine surgical approach from the aspect of the anatomic relationship between RLN and cervical fascia. METHODS: Forty-two adult cadavers were dissected to observe the relationships between RLN and different cervical fascia layers. RESULTS: RLN pierced out the alar fascia from the inner edge of the carotid sheath in all cases, and the piercing position in 22 cases (52.4%) was located at the lower segment of T1. The enter point into visceral fascia of RLN was located at C7-T1 in 25 cases (59.5%). The middle layer of deep cervical fascia exhibited the most stable anatomic relationship with RLN at the carotid sheath confluence site. Pulling visceral sheath leftwards would significantly increase the RLN tension. CONCLUSION: Using the close and stable relationship between RLN and cervical fascia could help to avoid RLN injury in anterior cervical spine surgical approach. LEVEL OF EVIDENCE: 4.

Anatomical factors/countermeasures in/against iatrogenic injury of the deep branch of radial nerve in the Thompson approach via middle and proximal segments of forearm / Factores anatómicos/contramedidas en/contra la lesión iatrogénica del ramo profundo del nervio radial en el abordaje de Thompson a través de los segmentos medio y proximal del antebrazo

This study aimed to investigate the anatomical factors affecting iatrogenic injury of the deep branch of radial nerve during the Thompson approach and to propose corresponding countermeasures. Thompson approach was used to measure the horizontal/longitudinal distance from the position where the deep branch of radial nerve leaves the supinator to the ulnar margin of extensor carpi radialis brevis/humeroradial joint line. Measurements were obtained by using 48 adult cadaver specimens, which were used in teaching. We observed the lentor situation of the extensor digitorum and extensor carpi radialis brevis in proximal forearm segments and measured the distance from the deep branch of radial nerve to the humeroradial joint line at the lateral side of the radius in the neutral position of forearm rotation. The horizontal distance from the point where the deep branch of radial nerve leaves the inferior margin of supinator to the ulnar margin of extensor carpi radialis brevis was 1.3 ± 0.3 cm. The distance to the humeroradial joint line was 61.3 ± 17.6 mm. The distance to the lentor extent of extensor digitorum and extensor carpi radialis brevis at the distal part of humeroradial joint was 7.1 ± 2.1 cm. The distance from the deep branch of radial nerve to the humeroradial joint line at the lateral side of the radius is 3.2 ± 0.6 mm. Anatomical factors are observed in iatrogenic injury of the deep branch of radial nerve during the Thompson approach. Stretching the extensor digitorum before the dissection of the supinator is hazardous.

El objetivo de este estudio fue investigar los factores anatómicos que provocan la lesión iatrogénica del ramo profundo del nervio radial durante el abordaje de Thompson y proponer las contramedidas correspondientes. El abordaje de Thompson se utilizó para medir la distancia horizontal / longitudinal desde la posición en que el ramo profundo del nervio radial sale del músculo supinador hasta el margen ulnar del músculo extensor radial corto del carpo a nivel de la línea articular humeroradial. Las mediciones se obtuvieron utilizando 48 especímenes de cadáveres adultos, que se usaron en la enseñanza. Se observó la situación de los músculos extensor de los dedos y del extensor radial corto del carpo en los segmentos proximales del antebrazo y se midió la distancia desde el ramo profundo del nervio radial hasta la línea articular humeroradial en el margen lateral del radio en posición neutra de rotación del antebrazo. La distancia horizontal desde el punto en que el ramo profundo del nervio radial sale del margen inferior del músculo supinador hasta el margen ulnar del músculo extensor radial corto del carpo fue 1,3 ± 0,3 cm. La distancia a la línea articular humeroradial fue de 61,3 ± 17,6 mm. La distancia entre el músculo extensor de los dedos y el músculo extensor radial corto del carpo en la parte distal de la articulación humeroradial fue de 7,1 ± 2,1 cm. La distancia desde el ramo profundo del nervio radial a la línea articular humeroradial en el lado lateral del radio fue de 3,2 ± 0,6 mm. Se observan factores anatómicos en la lesión iatrogénica del ramo profundo del nervio radial durante el abordaje de Thompson. El estiramiento del extensor de los dedos antes de la disección del músculo supinador es peligroso.

Comparison of the Dynesys Dynamic Stabilization System and Posterior Lumbar Interbody Fusion for Lumbar Degenerative Disease.

BACKGROUND: There have been few studies comparing the clinical and radiographic outcomes between the Dynesys dynamic stabilization system and posterior lumbar interbody fusion (PLIF). The objective of this study is to compare the clinical and radiographic outcomes of Dynesys and PLIF for lumbar degenerative disease. METHODS: Of 96 patients with lumbar degenerative disease included in this retrospectively analysis, 46 were treated with the Dynesys system and 50 underwent PLIF from July 2008 to March 2011. Clinical and radiographic outcomes were evaluated. We also evaluated the occurrence of radiographic and symptomatic adjacent segment degeneration (ASD). RESULTS: The mean follow-up time in the Dynesys group was 53.6 ± 5.3 months, while that in the PLIF group was 55.2 ± 6.8 months. At the final follow-up, the Oswestry disability index and visual analogue scale score were significantly improved in both groups. The range of motion (ROM) of stabilized segments in Dynesys group decreased from 7.1 ± 2.2° to 4.9 ± 2.2° (P < 0.05), while that of in PLIF group decreased from 7.3 ± 2.3° to 0° (P < 0.05). The ROM of the upper segments increased significantly in both groups at the final follow-up, the ROM was higher in the PLIF group. There were significantly more radiographic ASDs in the PLIF group than in the Dynesys group. The incidence of complications was comparable between groups. CONCLUSIONS: Both Dynesys and PLIF can improve the clinical outcomes for lumbar degenerative disease. Compared to PLIF, Dynesys stabilization partially preserves the ROM of the stabilized segments, limits hypermobility in the upper adjacent segment, and may prevent the occurrence of ASD.

Comparison of Functional and Radiological Outcomes Between Two Posterior Approaches in the Treatment of Multilevel Cervical Spondylotic Myelopathy.

BACKGROUND: Posterior cervical decompression is an accepted treatment for multilevel cervical spondylotic myelopathy (CSM). Each posterior technique has its own advantages and disadvantages. In the present study, we compared the functional and radiological outcomes of expansive hemilaminectomy and laminoplasty with mini titanium plate in the treatment of multilevel CSM. METHODS: Forty-four patients with multilevel CSM treated with posterior cervical surgery in Department of Orthopedic Surgery, Beijing Army General Hospital from March 2011 to June 2012 were enrolled in this retrospective study. Patients were divided into two groups by surgical procedure: Laminoplasty (Group L) and hemilaminectomy (Group H). Perioperative parameters including age, sex, duration of symptoms, operative duration, and intraoperative blood loss were recorded and compared. Spinal canal area, calculated using AutoCAD ® software(Autodesk Inc., San Rafael, CA, USA), and neurological improvement, evaluated with Japanese Orthopedic Association score, were also compared. RESULTS: Neurological improvement did not differ significantly between groups. Group H had a significantly shorter operative duration and significantly less blood loss. Mean expansion ratio was significantly greater in Group L (77.83 ± 6.41%) than in Group H (62.72 ± 3.86%) (P < 0.01). CONCLUSIONS: Both surgical approaches are safe and effective in treating multilevel CSM. Laminoplasty provides a greater degree of enlargement of the spinal canal, whereas expansive hemilaminectomy has the advantages of shorter operative duration and less intraoperative blood loss.

Differentiation of adipose-derived stem cells toward nucleus pulposus-like cells induced by hypoxia and a three-dimensional chitosan-alginate gel scaffold in vitro.

BACKGROUND: Injectable three-dimensional (3D) scaffolds have the advantages of fluidity and moldability to fill irregular-shaped defects, simple incorporation of bioactive factors, and limited surgical invasiveness. Adipose-derived stem cells (ADSCs) are multipotent and can be differentiated toward nucleus pulposus (NP)-like cells. A hypoxic environment may be important for differentiation to NP-like cells because the intervertebral disc is an avascular tissue. Hence, we investigated the induction effects of hypoxia and an injectable 3D chitosan-alginate (C/A) gel scaffold on ADSCs. METHODS: The C/A gel scaffold consisted of medical-grade chitosan and alginate. Gel porosity was calculated by liquid displacement method. Pore microstructure was analyzed by light and scanning electron microscopy. ADSCs were isolated and cultured by conventional methods. Passage 2 BrdU-labeled ADSCs were co-cultured with the C/A gel. ADSCs were divided into three groups (control, normoxia-induced, and hypoxia-induced groups). In the control group, cells were cultured in 10% FBS/DMEM. Hypoxia-induced and normoxia-induced groups were induced by adding transforming growth factor-ß1, dexamethasone, vitamin C, sodium pyruvate, proline, bone morphogenetic protein-7, and 1% ITS-plus to the culture medium and maintaining in 2% and 20% O2, respectively. Histological and morphological changes were observed by light and electron microscopy. ADSCs were characterized by flow cytometry. Cell viability was investigated by BrdU incorporation. Proteoglycan and type II collagen were measured by safranin O staining and the Sircol method, respectively. mRNA expression of hypoxia-inducing factor-1α (HIF-1α), aggrecan, and Type II collagen was determined by reverse transcription-polymerase chain reaction. RESULTS: C/A gels had porous exterior surfaces with 80.57% porosity and 50-200 üm pore size. Flow cytometric analysis of passage 2 rabbit ADSCs showed high CD90 expression, while CD45 expression was very low. The morphology of induced ADSCs resembled that of NP cells. BrdU immunofluorescence showed that most ADSCs survived and proliferated in the C/A gel scaffold. Scanning electron microscopy showed that ADSCs grew well in the C/A gel scaffold. ADSCs in the C/A gel scaffold were positive for safranin O staining. Hypoxia-induced and normoxia-induced groups produced more proteoglycan and Type II collagen than the control group (P < 0.05). Proteoglycan and Type II collagen levels in the hypoxia-induced group were higher than those in the normoxia-induced group (P < 0.05). Compared with the control group, higher mRNA expression of HIF-1α, aggrecan, and Type II collagen was detected in hypoxia-induced and normoxiainduced groups (P < 0.05). Expression of these genes in the hypoxia-induced group was significantly higher than that in the normoxia-induced group (P < 0.05). CONCLUSION: ADSCs grow well in C/A gel scaffolds and differentiate toward NP-like cells that produce the same extracellular matrix as that of NP cells under certain induction conditions, which is promoted in a hypoxic state.

Association analysis between g.18873C>T and g.27522G>A genetic polymorphisms of OPG and bone mineral density in Chinese postmenopausal women.

Several studies report that the OPG is an important candidate gene in the pathogenesis of osteoporosis. This study aimed to detect the potential association of OPG gene polymorphisms with osteoporosis in postmenopausal women. We recruited 928 subjects containing 463 with primary postmenopausal osteoporosis and 465 healthy volunteers as controls. The BMD of neck hip, lumbar spine (L(2-4)), and total hip were assessed by dual-energy X-ray absorptiometry (DEXA). Through the created restriction site-polymerase chain reaction (CRS-PCR), PCR-restriction fragment length polymorphism (PCR-RFLP), and DNA sequencing methods, the g.18873C>T and g.27522G>A have been investigated. As for g.18873C>T, our data indicated that subjects with CC genotype have significantly higher BMD value than those of CT and TT genotypes (all P values < 0.05). As for g.27522G>A, the BMD values of subjects with GG genotype were significantly higher than those of GA and AA genotypes (all P values < 0.05). Our findings suggest that the OPG g.18873C>T and g.27522G>A genetic polymorphisms are associated with the decreased risk for osteoporosis in Chinese postmenopausal women.

Dynesys dynamic stabilization system for the lumbar degenerative disease: a preliminary report from China.

BACKGROUND: Dynesys dynamic stabilization system was first implanted in patients in 1994, and introduced to China in 2007. Therefore, it was a new technique for Chinese orthopedics and hence necessary to collect clinical data about Dynesys in China. The objective of this study was to report the preliminary results of Dynesys for the lumbar degenerative disease in China. METHODS: Twenty-seven patients were treated with the Dynesys between July 2007 and January 2009. The diagnosis included degenerative spondylolisthesis (12 cases), degenerative spinal stenosis (nine cases), and lumbar intervertebral disc herniation (six cases). Back pain and leg pain were evaluated using 100-mm visual analog scales (VAS). The Oswestry Disability Index (ODI) was used to evaluate the patients' function. The intervertebral disc height and range of motion at the operative level were taken on radiographs. RESULTS: All the patients were followed-up, with an average of (22.40 ± 4.23) months (range 15-32 months). VAS of back pain and leg pain were improved significantly (P < 0.05) at follow-up. The ODI scores were reduced from (62.58 ± 12.01)% preoperatively to (15.01 ± 5.71)% at follow-up (P < 0.05). The preoperative mean height of the intervertebral disc was (11.21 ± 1.58) mm (range 8.5-13.8 mm) and mean was (10.10 ± 1.78) mm (range 7.0-13.4 mm) at follow-up (P < 0.05). The mean range of motion of the implanted segment was (6.00 ± 1.79)° (range 2.5-9.3°) preoperatively and (5.47 ± 1.27)° (range 2.9-7.8°) at follow-up (P = 0.11). CONCLUSIONS: The preliminary results of Dynesys for the lumbar degenerative disease in China are similar to the published results of other countries. It can significantly improve the clinic symptoms and preserved motion at the level of implantation. However, the long-term follow-up data need to be collected.

[Effects of vertebral height restoration of vertebroplasty for osteoporotic vertebra compression fractures].

OBJECTIVE: To evaluate the effect of vertebral height restoration of vertebroplasty for osteoporotic vertebra compression fractures (VCFs). METHODS: From October 2004 to June 2007, a total of 37 patients with 40 VCFs were treated by vertebroplasty. There were 12 males and 25 females with a mean age of (72.4 +/- 12.7) years (ranged, 48 to 87). Pain easement state was evaluated by visual analog scale (VAS) before and after operation, as well as in followed-up. Preoperative and postoperative vertebral height, kyphosis angle at fractured levels were measured on X-rays. RESULTS: All of patients were followed-up for 12 to 47 months (averaged, 35.8 +/- 9.6). The VAS score was 8.4 +/- 1.6 before operative, 2.1 +/- 1.2 at the 2nd day after operative, there were significant difference between pre-and postoperative (P < 0.05); the average follow-up VAS was 1.6 +/- 0.9, there were significant difference as compared with the preoperative (P < 0.05). Lateral X-ray showed that the preoperative degree of vertebral height in the of anterior and middle vertebral were (72.0 +/- 10.6)% and (68.0 +/- 15.6)%, and postoperative were (76.0 +/- 8.6)% and (73.0 +/-6.1)%, respectively. There were no significant difference in vertebral height between preoperative and postoperative. The vertebral kyphosis angle was corrected from preoperative (7.8 +/- 2.7) degree to postoperative (8.1 +/- 2.3) degree. CONCLUSION: Vertebroplasty is a safe and effective method for treatment of osteoporotic VCFs, it can relieve the pain effectively. Failure to restore vertebaral height does not seem to interfere with the excellent pain management.

[Step treatment strategy of degenerative lumbar scoliosis and spinal stenosis].

OBJECTIVE: Degenerative lumbar scoliosis and spinal stenosis are more common in elderly patients. Because of many factors, treatment choices are more complex. To investigate the step treatment strategy of degenerative lumbar scoliosis and spinal stenosis. METHODS: Between January 2005 and December 2009, 117 patients with degenerative lumbar scoliosis and spinal stenosis were treated with step treatment methods, including conservative therapy (43 cases), posterior decompression alone (18 cases), posterior short segment fusion (1-2 segments, 41 cases), and posterior long segment fusion (> or = 3 segments, 15 cases). Step treatment options were made according to patient's will, the medical complications, the degree of the symptoms of low back and lower extremity pain, the size of three-dimensional lumbar scoliosis kyphosis rotating deformity, lumbar spine stability (lateral slip, degenerative spondylolysis), and the overall balance of the spine. The visual analogue scale (VAS) score of low back and lower extremity pain, Oswestry disability index (ODI), lumbar lordosis angle, and scoliosis Cobb angle were measured and compared before and after treatments. RESULTS: Seventy-two cases were followed up more than 12 months, and there was no death or internal fixation failure in all patients. Of them, 19 patients underwent conservative treatment; the mean follow-up period was 19.3 months (range, 1-5 years); no symptom deterioration was observed; VAS score of low back and lower extremity and ODI were significantly decreased at last follow-up (P < 0.05); and lordosis angle was decreased and scoliosis Cobb angle was increased, but there was no significant difference (P > 0.05). Twelve cases underwent posterior decompression alone; the average follow-up was 36 months (range, 1-5 years); VAS score of lower extremity and ODI were significantly decreased at last follow-up (P < 0.05); and scoliosis Cobb angle was increased and lordosis angle was decreased, but there was no significant difference (P > 0.05). Thirty-one patients underwent posterior short segment fusion; the mean follow-up period was 21.3 months (range, 1-3 years); postoperative hematoma, poor wound healing, cerebrospinal fluid leakage, and superficial infection occurred in 1 case, respectively, and were cured after symptomatic treatment; VAS score of low back and lower extremity and ODI were significantly decreased (P < 0.05); and postoperative lumbar scoliosis Cobb angle and lordosis angle were significantly improved at last follow-up (P < 0.05). Ten patients underwent posterior long segment fusion; the mean follow-up period was 17.1 months (range, 1-3 years); postoperative symptoms worsened in 1 case and was cured after physical therapy and drug treatment for 3 months, and deep infection occurred in 1 case and was cured after debridement and continuous irrigation drainage; VAS score and ODI were significantly decreased (P < 0.05); and postoperative scoliosis Cobb angle and lordosis angle were improved significantly at last follow-up (P < 0.05). CONCLUSION: The treatment of degenerative lumbar scoliosis and spinal stenosis should be individual and step. Surgery treatment should be rely on decompression while deformity correction subsidiary. Accurate judgment of the responsible segment of symptoms, scoliosis and lordosis can prevent the operation expansion and increase safety of surgery with active control bleeding.

[Clinical classification and surgical options of the far-lateral lumbar disc herniation].

OBJECTIVES: To suggest the clinical classification of the far-lateral lumbar disc herniation and offer the considerations for clinical choice of different surgical procedures. METHODS: According to the locations of the herniated disc and relevant clinical symptoms, the far-lateral lumbar disc herniation was divided into three types: Type I: posterolateral and foraminal herniation(double herniations); Type II: foraminal disc herniation and Type III: extraforaminal herniation. From January 2002 to January 2007, 38 patients with far lateral lumbar disc herniation underwent surgery in the institute. The surgical options were decided by means of the classification. The surgical procedures included (1) discectomy by inter-TP (transverse process) approach, (2) discectomy with partial facetectomy and (3) discectomy with facetectomy and PLIF (posterior lumbar interbody fusion). Among the 38 patients, there were 25 males and 13 females. The mean age was 58.4 years old. The herniated discs located at L(3-4) in 17, L(4-5) in 13, and 8 cases at L(5)S(1). Twenty-three patients were simple disc herniation, 15 cases with concomitant lumbar spinal stenosis. The symptoms and signs of exiting root compression at herniated disc level were presented in all patients and passing root compression presented in 7 Type I cases as well; while intermittent claudication being presented in 15 and low back pain in 21 patients. The VAS (visual analog pain scale) of radicular leg pain was taken before and after the operation. The postoperative outcomes were evaluated through the MacNab's method in all the patients. RESULTS: By using the new classification system, the 38 patient were divided into Type I 10 cases, Type II 19 cases and Type III 9 cases. The adopted surgeries included discectomy by intertransverse approach in 5, discectomy with partial facetectomy in 7, and discectomy with facetectomy and PLIF in the rest 26 cases. The mean follow-up period was ranging from 6 months to 4 years and 10 months, average 2 years and 11 months. The mean VAS scores of radicular pain was 7.4 preoperatively, 2.7 at 2 weeks after the operation and 3.1 at final follow-up. The final clinical outcomes by MacNab's method were as follow: excellent results in 20 cases, good in 12, fair in 5 and poor in 1 case. The overall improvement ratio was 84.2%. The postoperative complications included superficial wound infection in 1 case, insufficient decompression in 1 case and leakage of cerebrospinal fluid in 1 case respectively. No breakage and loosening of internal fixation were detected. CONCLUSIONS: A new clinical classification of far lateral lumbar disc herniation was suggested, which is significant to understanding the relevant pathology and choosing the surgical procedures.