The Role of Immunocyte Infiltration Regulatory Network Based on hdWGCNA and Single-Cell Bioinformatics Analysis in Intervertebral Disc Degeneration.

Immune infiltration plays a crucial role in intervertebral disc degeneration (IDD). In this study, we explored the immune microenvironment of IDD through single-cell bioinformatics analysis. Three single-cell datasets were integrated into this study. Nucleus pulposus cells (NPCs) were divided into subgroups based on characteristic genes, and the role of each subgroup in the IDD process was analyzed through pseudo-time trajectory analysis. The hub genes were obtained using hdWGCNA, further identified by bulk datasets and pseudo-time sequence. The expression of the hub genes defined the NPCs related to immune infiltration, and the interaction between these NPCs and immunocytes was explored. The NPCs were divided into four subgroups: reserve NPCs, HCL-NPCs, response NPCs, and support NPCs, which, respectively, dominate the four processes of IDD: non, mild, moderate, and severe degeneration. SPP1 and ICAM1 were identified as the nucleus pulposus immune infiltration hub genes. Macrophages and myelocytes played pro-inflammatory roles in the SPP1-ICAM both-up NPC group through the SPP1-CD44 pathway and ICAM1-ITGB2 ligand-receptor pathway, respectively. At the same time, both-up NPCs sought self-help inflammation remission from neutrophils through the ANXA1-FPR1 pathway. The systematic analysis of the differentiation and immune infiltration landscapes helps to understand IDD's overall development process. Our data suggest that SPP1 and ICAM1 may be new targets for the treatment of inflammatory infiltration in IDD.

Small nucleolar RNA host gene 1 silence inhibits the lipopolysaccharide-induced microglial apoptosis and inflammation.

Microglia activation is an early mediator of neuroinflammation and a major contributor to spinal damage and motor dysfunction. This study was designed to investigate the role of small nucleolar RNA host gene 1 (SNHG1) on the apoptosis and inflammatory response of microglial cell BV-2 and its underlying molecular mechanism. The C5 lamina contusion-induced mouse model of spinal cord injury (SCI) was constructed. Mouse microglia BV2 was stimulated by lipopolysaccharide (LPS) to establish the in vitro model of SCI. The quantitative reverse transcription polymerase chain reaction method was used to quantify RNA expression levels. Enzyme-linked immunosorbent assays were used to quantify concentrations of inflammatory cytokines. Protein levels were assessed by western blotting, and apoptosis was assessed by flow cytometry. Dual luciferase reporter gene assay and RNA pull-down assay were conducted to investigate the binding relationships between molecules. Upregulation of SNHG1 and downregulation of miR-195-5p were observed in the spinal cords of SCI mouse model. LPS treatment led to elevation of SNHG1 expression in BV2 cells, as well as accelerated apoptosis and inflammation. Evident mitigation of LPS-induced BV2 cell damage was observed after SNHG1 knockdown. MiR-195-5p was identified as a target of SNHG1. Inhibition of miR-195-5p restored the impact of SNHG1 knockdown on cell damage of LPS-treated BV2 cells. Furthermore, miR-195-5p can target activating transcription factor-6 (ATF6). In summary, SNHG1 knockdown ameliorates LPS-induced microglial apoptosis and inflammatory response via the miR-195-5p/ATF6 axis, providing a novel direction for SCI treatment.

Comparison between percutaneous short-segment fixation and percutaneous vertebroplasty in treating Kummell's disease: A minimum 2-year follow-up retrospective study.

BACKGROUND: Percutaneous kyphoplasty (PKP) or percutaneous short-segment fixation (PSSF) is often used to treat Kummell's disease. However, it is not clear which treatment is better for patients. OBJECTIVE: To retrospectively compare the clinical efficacy of PVP and PSSF for the treatment of Kummell's disease. METHOD: 60 patients were involved in this research and the period of follow-up was at least 2 years. 27 of them were treated with PVP (Group I) and the rest who received PSSF (Group II). The visual analog scale (VAS) and radiographic indexes of each participant had been measured preoperatively as well as 1 week, 3 months, and 2 years postoperatively. Additionally, the Oswestry Disability Index (ODI) scores were assessed at the last time point. RESULTS: Comparing the two groups, no statistical significance was found among all parameters preoperatively. The time of operations and blood loss is less in Group I. At each time point after operation, the imaging indices in Group II are lower (P< 0.05). One week after treatments, the VAS scores are lower in Group I, and similarly, 3 months are the same (P< 0.05), while VAS are similar at the last time point. In the aspect of ODI scores, they are lower in Group II during long-term follow-up. CONCLUSION: For the treatment of Kummell's disease, both PVP and PSSF have been found to be effective. PVP can provide rapid pain relief with a shorter operation time. However, in cases with severe kyphosis deformity, PSSF should be given priority.

LncRNA RP11-59J16.2 aggravates apoptosis and increases tau phosphorylation by targeting MCM2 in AD.

Alzheimer's disease (AD) is a degenerative disease of central nervous system with unclear pathogenesis, accounting for 60%-70% of dementia cases. Long noncoding RNAs (LncRNAs) play an important function in the development of AD. This study aims to explore the role of differentially expressed lncRNAs in AD patients' serum in the pathogenesis of AD. Microarray analysis was performed in the serum of AD patients and healthy controls to establish lncRNAs and mRNAs expression profiles. GO analysis and KEGG pathway analysis revealed that G1/S transition of mitotic cell cycle might be involved in the development of AD. The result showed that RP11-59J16.2 was up-regulated and MCM2 was down-regulated in serum of AD patients. SH-SY5Y cells were treated with Aß 1-42 to establish AD cell model. Dual luciferase reporter gene analysis verified that RP11-59J16.2 could directly interact with 3'UTR of MCM2 and further regulate the expression of MCM2. Inhibition of RP11-59J16.2 or overexpression of MCM2, CCK-8 assay and Annexin V FITC/PI apoptosis assay kit results showed that RP11-59J16.2 could reduce cell viability, aggravate apoptosis and increase Tau phosphorylation in AD cell model by inhibiting MCM2. In short, our study revealed a novel lncRNA RP11-59J16.2 that could promote neuronal apoptosis and increase Tau phosphorylation by regulating MCM2 in AD model, and indicated that lncRNA RP11-59J16.2 might be a potential target molecule for AD development.

Comparison between gravity drainage group and suction drainage group after cervical laminoplasty: a retrospective STROBE-compliant cohort study.

OBJECTIVES: A retrospective study was conducted to compare gravity drainage and suction drainage after cervical laminoplasty. PATIENTS AND METHODS: A total of 375 patients who underwent laminoplasty between January 2011 and December 2015 were engaged in this analysis. We investigated the patients' basic characteristics, drainage characteristics and postoperative complications. RESULTS: During the initial 24 h after laminoplasty, the drainage volume in the suction drainage group was 177.31 ± 92.02 mL, and the drainage volume in the gravity drainage group was 133.33 ± 92.40 mL. The drainage volume showed significant difference (p < 0.01). The total drainage volume was 357.49 ± 195.16 mL and 250.16 ± 27.44 mL in the suction drainage group and gravity drainage group, respectively. The total drainage volume between the two groups was statistically different (p = 0.03). The postoperative Hb was significantly different between the gravity group and suction group on the first day after the operation (108.37 ± 23.92 mL vs. 87.32 ± 21.53 mL, p = 0.02). The number of patients required blood transfusion was significantly different between the two groups as well (p = 0.04). Two cases had symptomatic epidural hematomas (SEH) after laminoplaty. However, the occurrence of SEH among the two groups was not different significantly. Twelve patients had surgical site infection (SSI). Of these 12, nine had applied gravity drainage and three suction drainage. The rate of SSI was similar between the two groups (p = 0.71). CONCLUSION: The initial 24 h' drainage volume and the total drainage volume increased significantly in the suction drainage group. The postoperative Hb was lower in the suction group than the gravity drainage group the first postoperative day. More patients needed blood transfusion if suction drainage was performed. The application of suction drainage cannot decrease the incidence of SSI and SEH after laminoplasty. Gravity drainage is recommended for laminoplasty.

"Sandwich" wound dressing to reduce surgical site infections during sacrococcygeal surgery: A retrospective analysis.

OBJECTIVE: To explore whether the "sandwich" wound dressing method with a hydrocolloid dressing can effectively reduce surgical site infection rates in sacrococcygeal aseptic operations. METHODS: A retrospective cohort of patients with sacrococcygeal aseptic operations (class I incision category) from January 2017 to March 2018 were divided into intervention (sandwich dressing) and control groups (conventional dressing). The surgical site infections (SSI) rate, wound healing course, hospitalization time, and medical costs in the two groups were determined. To exclude the influence of other factors, operation time, blood loss, age, sex ratio, the distance of the incision from the distal edge to the anus, and initial defecation times were compared between the groups. RESULTS: The SSI rates and medical costs in the interventional group were significantly lower than the control group (0% vs 78.57%, P < 0.0001; 3.27 ±â€¯0.98 vs 5.83 ±â€¯1.66 ¥10,000, p < 0.0001). Hospitalization times were also lower in the intervention compared to the control group (17.05 ±â€¯4.77 vs 34.50 ±â€¯15.47 day, P = 0.001). CONCLUSIONS: The sandwich wound dressing method with a hydrocolloid dressing can effectively prevent SSI during sacrococcygeal aseptic surgery.

Predictor of Surgical Outcomes in Ankylosing Spondylitis Cervical Spinal Fracture: An At Least 2 Years Follow-Up Retrospective Study.

STUDY DESIGN: Retrospective study. OBJECTIVE: A retrospective study was conducted to clarify the prognostic factors of postoperative for cervical spine fractures patients with ankylosing spondylitis (AS). SUMMARY OF BACKGROUND DATA: Now the high probability of cervical fractures in patients with AS is unanimously recognized. Fractures mostly occur in the lower cervical spine and two-thirds of patients are accompanied by spinal cord injury. But there are few studies on treatment of AS patients with cervical fracture and it is unclear whether the surgical method, timing of surgery, basic treatment of AS, and different doses of steroids therapy have an impact on the prognosis. Thus, this study aims to evaluate the impact of perioperative factors on the prognosis of traumatic cervical fractures in surgical patients with AS. METHODS: Preoperative and postoperative spinal cord function were assessed according to the Japanese Orthopaedic Association (JOA) Scores and Improvement rate were calculated. The neck pain severity were rated using a visual analogue scale (VAS) score. The t test and v2-test were used for comparison of clinical data between the preoperative and postoperative groups. Logistic univariate and multivariate regression analysis were used to obtain adjusted odds ratios. Pearson correlation coefficients were used to evaluate the relationship between variables. RESULTS: The degree of fracture displacement in cervical spine fractures patients with AS was most common at the neck-chest junction (26.1%). Patients with degree of cervical fracture displacement less than 50% had significantly improved JOA scores after surgery (P = 0). The incidence of spinal cord injury (SCI) due to fracture was high (52.2%). Patients with combined anterior and posterior is helpful for neurological recovery (P = 0.01). Basic AS treating before injury would be benefit for neurological improvement (P = 0). CONCLUSION: Basic AS treatment, SCI, and surgical methods are independent factors that affect the prognosis of cervical spine fractures patients with AS. It is controversial to perform surgery and preoperative steroid application as soon as possible. LEVEL OF EVIDENCE: 3.

Indirect Decompression Failure After Lateral Lumbar Interbody Fusion-Reported Failures and Predictive Factors: Systematic Review.

BACKGROUND: In patients with symptomatic lumbar stenosis undergoing lateral transpsoas approach for lumbar interbody fusion (LLIF) surgery, it is not always clear when indirect decompression is sufficient in order to achieve symptom resolution. Indirect decompression failure (IDF), defined as "postoperative persistent symptoms of nerve compression with or without a second direct decompression surgery to reach adequate symptom resolution," is not widely reported. This information, however, is critical to better understand the indications, the potential, and the limitations of indirect decompression. OBJECTIVE: The purpose of this study was to systematically review the current literature on IDF after LLIF. METHODS: A literature search was performed on PubMed. We included randomized controlled trials and prospective, retrospective, case-control studies, and case reports. Information on sample size, demographics, procedure, number and location of involved levels, follow-up time, and complications were extracted. RESULTS: After applying the exclusion criteria, we included 9 of the 268 screened articles that reported failure. A total of 632 patients were screened in these articles and detailed information was provided. Average follow-up time was 21 months. Overall reported incidence of IDF was 9%. CONCLUSION: Failures of decompression via LLIF are inconsistently reported and the incidence is approximately 9%. IDF failure in LLIF may be underreported or misinterpreted as a complication. We propose to include the term "IDF" as described in this article to differentiate them from complications for future studies. A better understanding of why IDF occurs will allow surgeons to better plan surgical intervention and will avoid revision surgery.

Transdural Approach to Resection of Intraspinal Extradural Ventral Cysts in the Lumbar Spine.

BACKGROUND: Intraspinal extradural ventral cysts in the lumbar spine can cause back pain and neurological deficits of the lower extremities. For the resection of this type of space-occupying lesion, the transdural approach has not been reported in the literature. CASE DESCRIPTION: A 66-year-old man presented, suffering from progressive radiation pain of his bilateral lower extremities. Imaging examination revealed a cystic lesion in ventral side of lumbar spinal canal. We conducted the excision of the cyst with the transdural approach. The symptoms of the patient disappeared immediately after the operation and recurrence of the symptoms has not been observed in the 3-month follow-up. CONCLUSIONS: This operation approach is safe and effective. Compared with the previous surgical approach reported in the literature, by this approach surgeons could achieve less injury, shorter operation time, and the same surgical outcomes in the short term. Therefore, we would like to present this approach to provide an alternative to deal with similar lesions.

Variation in greater trochanteric lateroversion: a risk factor for femoral stem varus in total hip arthroplasty.

INTRODUCTION: Correct implant positioning is required to achieve adequate biomechanics. The greater trochanter is more medially or laterally positioned in some patients, known as trochanteric lateroversion. However, studies have not identified correlations between postoperative coronal alignment and variation in greater trochanteric lateroversion. The purpose of this study was to identify the effects of variation in greater trochanteric lateroversion on postoperative stem coronal alignment and to investigate other factors related to stem coronal alignment. METHODS: A total of 213 hips in 149 patients who underwent total hip arthroplasty were included in this prospective study. The greater trochanters were categorised into 5 groups according to the degree of variation in greater trochanteric lateroversion, and the stem coronal alignment angle and stem fit were measured on anteroposterior radiographs. RESULTS: Postoperative stem varus was positively correlated with greater trochanteric lateroversion (r = 0.26065, p = 0.0001) and negatively correlated with the stem fit (r = -0.16568, p = 0.0155). DISCUSSION: Excessive variation in greater trochanteric lateroversion was a risk factor for femoral stem varus, and the stem varus position was always accompanied by inadequate canal filling. When the tip of the trochanteric overhang exceeded the centreline of the femoral canal, the influence of lateroversion of the greater trochanter on the femoral stem remarkably increased. Appropriate measures should be implemented to avoid a stem varus position and inappropriate stem fit.

Circular RNA LARP4 correlates with decreased Enneking stage, better histological response, and prolonged survival profiles, and it elevates chemosensitivity to cisplatin and doxorubicin via sponging microRNA-424 in osteosarcoma.

BACKGROUND: This study aimed to evaluate the association of circular RNA La-related RNA-binding protein 4 (circ-LARP4) with clinical features and prognosis in osteosarcoma patients, and further explore its effect on chemosensitivity in osteosarcoma cells. METHODS: Seventy-two osteosarcoma patients with Enneking stage IIA-IIB who underwent resection were consecutively enrolled, and then, tumor tissues and non-tumor tissues were obtained. Circ-LARP4 in tumor tissue/non-tumor tissue was detected by quantitative polymerase chain reaction. After circ-LARP4 overexpression and negative control overexpression plasmid transfection, relative cell viability (%) was evaluated by Cell Counting Kit-8 in MG63 cells treated by different concentrations of cisplatin, methotrexate, and doxorubicin, and IC50 was calculated. RESULTS: Circ-LARP4 was downregulated in tumor tissue compared with non-tumor tissue and had a good value in distinguishing tumor tissue from non-tumor tissue with an area under curve of 0.829 (95% CI: 0.762-0.859). Meanwhile, tumor circ-LARP4 was negatively correlated with the Enneking stage. After resection, circ-LARP4 high expression patients showed an increased tumor cell necrosis rate to adjuvant chemotherapy compared to circ-LARP4 low expression patients, and circ-LARP4 high expression correlated with prolonged disease-free survival and overall survival. In vitro experiments revealed that circ-LARP4 overexpression elevated the chemosensitivity of MG63 cells to cisplatin and doxorubicin but not methotrexate, with decreased cisplatin IC50 and doxorubicin IC50 concentrations than negative control. Besides, miR-424 overexpression attenuated the chemosensitivity in circ-LARP4 overexpression-treated MG63 cells. CONCLUSION: Circ-LARP4 high expression correlates with decreased Enneking stage and prolonged survival profiles, and it elevates chemosensitivity to cisplatin and doxorubicin via sponging miR-424 in osteosarcoma.

Risk factors of postoperative low back pain for low-grade isthmic spondylolisthesis: a retrospective study.

OBJECTIVE: To investigate the risk factors of postoperative low back pain (LBP) following posterior lumbar interbody fusion (PLIF) surgery for low-grade isthmic spondylolisthesis (IS). METHODS: This retrospective study enrolled patients with IS that underwent PLIF between January 2011 and January 2016. Demographic, clinical, surgical and radiological characteristics were analysed to determine associations between these characteristics and LBP as measured using a visual analogue scale (VAS) pain score. RESULTS: A total of 192 patients were enrolled in the study. The mean VAS pain score of LBP decreased significantly after surgery. The mean preoperative VAS pain score was significantly greater in patients with symptoms of ≤3 years duration compared with those with symptoms lasting >3 years. The postoperative VAS pain score was significantly lower in patients with grade 1 slippage compared with those with grade 2 slippage. There was a significant correlation between preoperative to postoperative change of VAS pain score and postoperative disc height (r = 0.99). CONCLUSION: PLIF significantly improved LBP in patients with low-grade IS, although patients still reported some postoperative LBP. The grade of slippage was a risk factor for postoperative LBP. Restoring the disc height appeared to improve LBP.

The long noncoding RNA HOTAIR serves as a microRNA-34a-5p sponge to reduce nucleus pulposus cell apoptosis via a NOTCH1-mediated mechanism.

Intervertebral disc degeneration (IDD) is a major cause of lower back pain, but the specific molecular mechanisms governing its development are poorly characterized. This study sought to assess to what extent HOTAIR, a long non-coding (Lnc) RNA is expressed in IDD and regulates the apoptotic death of nucleus pulposus (NP) cells. We therefore used real-time qPCR to measure HOTAIR and microRNA(miR)-34a-5p in degenerative NP cells, and then validated their functional relevance via overexpressing them in these NP cells. We further verified the targets of these RNA constructs in 293 T cells through the use of a dual luciferase reporter assay. We further measured NP cell apoptosis via flow cytometry and Notch1 expression via western blotting. Our results indicated that IDD was linked with decreased HOTAIR expression relative to regular NP cells, and overexpressing this lncRNA was linked to reduced apoptotic NP cell death, whereas overexpressing miR-34a-5p had the opposite effect. We found that HOTAIR served as a miR-34a-5p sponge, sequestering this miRNA and thereby down regulating genes linked to apoptosis through the Notch signaling pathway. Even in naturally degenerated NP cells, HOTAIR delayed the onset of apoptosis. Together these results reveal that a HOTAIR/miR-34a-5p/Notch1 signaling pathway may regulate the development of IDD, potentially making HOTAIR a viable target for treatment of this disease.

Risk Factors of Postoperative Sacroiliac Joint Pain for Posterior Lumbar Surgery: ≥2-Year Follow-up Retrospective Study.

PURPOSE: A retrospective study was conducted to clarify the risk factors of postoperative sacroiliac joint pain (SIJP) for posterior open lumbar surgery. PATIENTS AND METHODS: A total of 472 patients who underwent posterior lumbar surgery between January 2011 and December 2014 were included in this analysis. We recorded basic characteristics, surgical characteristics, and SIJP information for each patient. RESULTS: The incidence of postoperative SIJP is 13.8% in our study. Comparison of the incidence of SIJP between diskectomy and posterior lumbar interbody fusion indicated that SIJP incidence tended to be higher in posterior lumbar interbody fusion patients (P = 0.029). Compared with the single-segment group, SIJP occurred more frequently in the multiple operative segments group (P = 0.025). Comparing the incidence of SIJP among different types of lumbar diseases, SIJP incidence is significantly higher in the lumbar stenosis group (P = 0035). CONCLUSION: Lumbar fusion surgery and multiple operative segments are interdependent risk factors for the postoperative SIJP. The incidence of postoperative SIJP also increases in patients with lumbar stenosis compared with lumbar disk herniation and lumbar spondylolisthesis.

Risk Factors of Postoperative Low Back Pain for Low-Grade Degenerative Spondylolisthesis: An At Least 2-Year Follow-Up Retrospective Study.

OBJECTIVE: A retrospective study was conducted to clarify the risk factors of postoperative low back pain (LBP) for low-grade degenerative spondylolisthesis. PATIENTS AND METHODS: A total of 239 patients who underwent posterior lumbar fusion between January 2011 and January 2015 were included in this analysis. We investigated patient characteristics, surgical characteristics, and radiographic characteristics. RESULTS: The mean visual analog scale (VAS) score of LBP decreased dramatically after the operation. The mean preoperative VAS score was greater in patients with severe lumbar multifidus (LM) intramuscular adipose tissue (IMAT). The postoperative VAS score was dramatically lower in patients with shorter symptom duration. Postoperative LBP disappeared more often in patients with shorter symptom duration. LBP VAS changing showed significant differences in different symptom duration groups and LM IMAT groups. CONCLUSIONS: LM IMAT and symptom duration were risk factors for postoperative LBP. Patients with severe LM IMAT reported more severe LBP before the operation. Postoperative LBP disappeared more often in patients with shorter symptom duration.

Risk Factors of Postoperative Low Back Pain for Lumbar Spine Disease.

PURPOSE: A retrospective study was conducted to clarify the risk factors of postoperative low back pain (LBP) for lumbar spine disease. PATIENTS AND METHODS: A total of 401 patients who underwent lumbar operation between January 2011 and December 2011 were included in this analysis. We investigated patient characteristics and surgical approaches and also compared the radiographic characteristics. RESULTS: The mean visual analogue scale (VAS) score decreased dramatically after the operation. The mean preoperative VAS score was greater in patients underwent posterior lumbar interbody fusion (PLIF) with longer duration of symptoms, longer operation time, and severe lumbar multifidus (LM) intramuscular adipose tissue (IMAT). The preoperative VAS score was dramatically lower in patients with lumbar herniation. The postoperative VAS score was dramatically lower in patients who underwent PLIF with longer operation time and mild LM IMAT. Postoperative LBP disappeared more often in patients who underwent PLIF with longer operation times. The number of operative levels and type of lumbar spine disease also were associated with postoperative LBP. CONCLUSION: Type of surgery, operation time, number of operative level, and type of disease were risk factors for the postoperative LBP. Patients underwent PLIF with shorter symptom duration, longer operation time severe LM IMAT, and lumber spondylolisthesis reported more severe LBP before the operation. Patients underwent discectomy with shorter operation times.

Predictors of Surgical Outcome in Acute Spinal Cord Injury Patients with Cervical Ossification of the Posterior Longitudinal Ligament.

OBJECTIVE: A retrospective study was conducted to clarify the predictors of the operation results for ossification of the posterior longitudinal ligament (OPLL) patients with acute spinal cord injury (SCI). Detailed analyses of surgical outcomes of OPLL patients with SCI have been rare because most surveys have aimed to investigate OPLL or SCI, but not both. PATIENTS AND METHODS: A total of 36 patients who underwent operation for OPLL between January 2011 and December 2011 were included in this analysis. We investigated the patients' characteristics and surgical approaches and compared the radiographic characteristics of OPLL patients with SCI. RESULTS: The mean modified Japanese Orthopaedic Association (mJOA) score improved dramatically after operation (P = 0.006). The mean preoperative mJOA score was greater in patients with Nurick 3 than in patients with Nurick 4 and 5 (P = 0.041). The preoperative mJOA score was dramatically lower in patients caused by traffic accident and in patients with segmental OPLL lesion (P < 0.05). The postoperative mJOA score was dramatically lower in patients with continuous OPLL lesion than in the segmental OPLL lesion (P = 0.028). Changing in mJOA score was significantly different between the patients with high-intensity zone (HIZ) and without HIZ on magnetic resonance imaging. CONCLUSIONS: HIZ on magnetic resonance imaging was significantly related to the surgical outcomes, which should be highlighted in the preoperative communication with patients. Patients with lower Nirick grade and segmental OPLL would show better symptom before the operation. In addition, SCI caused by slipping or falling showed better symptoms before the operation. Patients with segmental OPLL should show better resolution of symptoms after the operation.

Predictors of surgical outcome in ossification of the posterior longitudinal ligament.

STUDY DESIGN: A retrospective study. OBJECTIVE: To clarify the predictors of the operation results for ossification of the posterior longitudinal ligament (OPLL). SUMMARY OF BACKGROUND DATA: Detailed analyses of surgical outcomes of OPLL have been rare because most survey aimed to investigate cervical spondylotic myelopathy. METHODS: All patients who underwent cervical operation for OPLL between January 2011 and December 2011 were included in this analysis. We investigated the patients' characteristics and surgical approaches, and compared the radiographical characteristics of OPLL. RESULTS: The mean mJOA score improved from 8.312 ± 3.021 points preoperatively to 11.24 ± 3.43 points at 24 months after operation (P<0.001). The average change in mJOA score was significantly greater in patients with a higher Nirik score than in those with lower Nirik scores (P<0.0001). The average change in mJOA score was also significantly different in patients with trauma history (P<0.0001). The average recovery ratio was 42 ± 26.3% in young patients and 30 ± 31.6% in the group older than 50 years (P=0.012). The average recovery ratio in patients with acute and chronic symptoms was 48 ± 22.9% and 26 ± 33.9%, respectively. There was great difference between the two groups. CONCLUSION: OPLL patients with myelopathy would receive good result after the operation. Age and symptom duration are related to the surgical outcomes. Patients with lower Nirick grade and without trauma history would receive better results before and after the operation.

Aggrecan variable number of tandem repeat polymorphism and lumbar disc degeneration: a meta-analysis.

STUDY DESIGN: Data on the association between the ACAN (encoded for aggrecan core protein) variable number of tandem repeat (VNTR) polymorphism and lumbar disc degeneration are conflicting, so we performed a meta-analysis. OBJECTIVE: Aggrecan is involved in the shock absorbing function of the lumbar disc; we performed a meta-analysis to assess the association between ACAN VNTR and lumbar degeneration. SUMMARY OF BACKGROUND DATA: To perform a meta-analysis, we searched for studies published until September 2012, using electronic databases (PubMed, EMBASE, and China National Knowledge Infrastructure). Eight studies involving 965 cases of lumbar disc degeneration and 982 control subjects were identified. METHODS: Assessment for eligibility and extraction of data were performed by 2 independent investigators. We extracted allele frequency for each study. We calculated the pooled odds ratios (ORs) and 95% confidence intervals (CI) to assess the strength of the association between the ACAN VNTR polymorphism and lumbar disc degeneration risk. RESULTS: Results from the allele model suggested an increased risk of lumbar disc degeneration for the shorter alleles carriers compared with the normal alleles and longer alleles (OR = 1.54, 95% CI: 1.04-2.30, P = 0.03). In subgroup analysis by ethnicity, significant increased risks were found among Asians with shorter alleles (OR=1.65, 95% CI: 1.17-2.33, P = 0.004). CONCLUSION: Our results suggest an increased risk of shorter alleles compared with normal alleles and longer alleles against lumbar disc degeneration among populations especially among Asian descent. Such association may not be statistically significant in European populations.

Association of ADAMTS5 gene polymorphisms with osteoarthritis in Chinese Han population: a community-based case-control study.

Aggrecanase-2 (ADAMTS5) is reported to play essential roles in the pathophysiology of osteoarthritis (OA). To explore the relationship between ADAMTS5 gene polymorphisms and primary OA, we conducted a community-based case-control study. A total of 732 community residents aged 40-84 years participated in the community-based study in Northeast China. After taking physical examination and radiographic examination, 420 persons of the residents were diagnosed OA (216 women and 204 men). The other 312 individuals without any symptoms of osteoarthritis or signs in the radiographs (156 women and 156 men) were considered as healthy controls. After obtaining the DNA of patients and control group, genotypes of the ADAMTS5 gene polymorphisms were determined by polymerase chain reaction (PCR) followed by restriction enzyme digestion (HAEIII for P692L in exon 7 and BSRBI for R614H in exon 5). The numbers of patients with different OA subtypes were also calculated. The genotype and allele frequency of for the exon 5C/T BSRBI polymorphism was significantly different between OA patients and control individuals (P = 0.001, OR = 0.701, 95% CI = 0.569-0.863). This difference was more obvious in cervical OA patients (P = 0.001, OR = 0.664, 95% CI = 0.521-0.847). The mutation type of exon 5C/T BSRBI polymorphism would be a protective factor for OA especially for cervical OA. Our results suggest that the ADAMTS5 gene polymorphisms may contribute to the susceptibility of osteoarthritis in the Chinese Han population.