Jianxiong Ma

A methodological, systematic review of evidence-based independent risk factors for surgical site infections after spinal surgery

ObjectiveTo identify the independent risk factors, based on available evidence in the literature, for patients developing surgical site infections (SSI) after spinal surgery.MethodsNon-interventional studies evaluating the independent risk factors for patients developing SSI following spinal surgery were searched in Medline, Embase, Sciencedirect and OVID. The quality of the included studies was assessed by a modified quality assessment tool that had been previously designed for observational studies. The effects of studies were combined with the study quality score using a best-evidence synthesis model.ResultsThirty-six observational studies involving 2,439 patients with SSI after spinal surgery were identified. The included studies covered a wide range of indications and surgical procedures. These articles were published between 1998 and 2012. According to the quality assessment criteria for included studies, 15 studies were deemed to be high-quality studies, 5 were moderate-quality studies, and 16 were low-quality studies. A total of 46 independent factors were evaluated for risk of SSI. There was strong evidence for six factors, including obesity/BMI, longer operation times, diabetes, smoking, history of previous SSI and type of surgical procedure. We also identified 8 moderate-evidence, 31 limited-evidence and 1 conflicting-evidence factors.ConclusionAlthough there is no conclusive evidence for why postoperative SSI occurs, these data provide evidence to guide clinicians in admitting patients who will have spinal operations and to choose an optimal prophylactic strategy. Further research is still required to evaluate the effects of these above risk factors.

Balloon kyphoplasty versus percutaneous vertebroplasty in treating osteoporotic vertebral compression fracture: grading the evidence through a systematic review and meta-analysis

ObjectiveTo assess the safety and efficacy of balloon kyphoplasty (KP) compared with percutaneous vertebroplasty (VP) and provide recommendations for using these procedures to treat osteoporotic vertebral compression fractures (OVCF).MethodsA systematic search of all studies published through March 2012 was conducted using the MEDLINE, EMBASE, OVID, ScienceDirect and Cochrane CENTRAL databases. The randomized controlled trials (RCTs) and non-randomized controlled trials that compared KP to VP and provided data on safety and clinical effects were identified. Demographic characteristics, adverse events and clinical outcomes were manually extracted from all of the selected studies. The evidence quality levels and recommendations were assessed using the GRADE system.ResultsTwelve studies encompassing 1,081 patients met the inclusion criteria. Subgroup meta-analyses were performed according to the study design. In the RCT subgroup, there were significant differences between the two procedures in short-term visual analog scale (VAS), long-term kyphosis angles, operative times and anterior vertebrae heights. In the cohort study subgroup, there were significant differences between the two procedures in short- and long-term VAS, short- and long-term Oswestry Disability Index (ODI), cement leakage rates, short- and long-term kyphosis angles, operative times and anterior vertebrae heights. However, there were no significant differences in long-term VAS or adjacent vertebral fracture rates in the RCT subgroup. There were no significant differences in short- or long-term VAS, short- or long-term ODI, cement leakage rates, adjacent vertebral fracture rates, short- or long-term kyphosis angles or anterior vertebrae heights in the CCT subgroup, and the adjacent vertebral fracture rates did not differ significantly in the cohort study subgroup. The overall GRADE system evidence quality was very low, which lowers our confidence in their recommendations.ConclusionsKP and VP are both safe and effective surgical procedures for treating OVCF. KP may be superior to VP in patients with large kyphosis angles, vertebral fissures, fractures in the posterior edge of the vertebral body or significant height loss in the fractured vertebrae. Due to the poor quality of the evidence currently available, high-quality RCTs are required.

A meta-analysis of balloon kyphoplasty compared to percutaneous vertebroplasty for treating osteoporotic vertebral compression fractures

A meta-analysis was conducted to assess the safety and efficacy of balloon kyphoplasty (KP) compared to percutaneous vertebroplasty (VP) in the treatment of osteoporotic vertebral compression fractures (OVCF). Ten studies, encompassing 783 patients, met the inclusion criteria. Overall, the results of the meta-analysis indicated that there were significant differences between the two groups in the long-term kyphosis angle (mean difference [MD] = -2.64, 95% confidence interval [CI] = -4.66 to -0.61; p = 0.01), the anterior height of the vertebral body (MD = 3.67, 95% CI = 1.40 to 5.94; p = 0.002), and the cement leakage rates (risk ratio [RR] = 0.70, 95% CI = 0.52 to 0.95; p = 0.02). However, there were no significant differences in the short-term visual analog scale (VAS) scores (MD = -0.57, 95% CI -1.33 to 0.20; p = 0.15), the long-term VAS scores (MD = -0.99, 95% CI = -2.29 to 0.31; p = 0.14), the short-term Oswestry Disability Index (ODI) scores (MD = -6.54, 95% CI = -14.57 to 1.48; p = 0.11), the long-term ODI scores (MD=-2.01, 95% CI = -11.75 to 7.73; p = 0.69), the operation time (MD = 4.47, 95% CI = -0.22 to 9.17; p = 0.06), the short-term kyphosis angle (MD = -2.25, 95% CI = -5.14 to 0.65; p = 0.13), or the adjacent-level fracture rates (RR = 1.52, 95% CI = 0.76 to 3.03; p = 0.24). This meta-analysis demonstrates that KP and VP are both safe and effective surgical procedures for treating OVCF. Compared with VP, KP can significantly relieve a long-term kyphosis angle, improve the height of the vertebral body, and reduce the incidence of bone cement leakage. However, because of the limitations of this meta-analysis, a large randomized controlled trial is required to confirm our findings.

A meta-analysis of cervical arthroplasty compared to anterior cervical discectomy and fusion for single-level cervical disc disease

There is no consensus on whether anterior cervical arthroplasty or anterior cervical discectomy and fusion (ACDF) is the optimal treatment for single-level cervical radiculopathy or myelopathy. We conducted a meta-analysis of randomized controlled trials to compare the safety and efficacy of anterior cervical arthroplasty with ACDF. Eight studies met the inclusion criteria. Overall, there were significant differences between these two treatment approaches in the arm visual analog scale (VAS) scores [mean difference (MD)=-4.86, 95% confidence interval (CI)=-6.42 to -3.30], neck VAS scores (MD=-7.90, 95% CI=-10.36 to -5.44), overall success rate [odds ratio (OR)=1.84, 95% CI=1.43 to 2.36], neurological success rate (OR=1.75, 95% CI=1.20 to 2.55), and incidence of reoperation [risk ratio (RR)=0.50, 95% CI=0.26 to 0.97]. However, there were no significant differences in the neck disability index (NDI) scores (MD=-3.81, 95% CI=-8.12 to 0.51), number of adverse events (RR=0.77, 95% CI=0.48 to 1.23), or radiological success rate (OR=0.87, 95% CI=0.36 to 2.09). Based on this meta-analysis, cervical arthroplasty is a safe and effective surgical procedure for treating single-level cervical radiculopathy or myelopathy.

Risk factors for new vertebral compression fractures after percutaneous vertebroplasty: qualitative evidence synthesized from a systematic review.

Study Design. Methodological systematic review. Objective. To identify the risk factors for new vertebral compression fractures (VCFs) in patients after percutaneous vertebroplasty (PVP) and to grade the evidence according to the quality of included studies. Summary of Background Data. PVP is an effective procedure for the treatment of VCFs. A major concern after PVP in patients with osteoporosis is the occurrence of new VCFs in the untreated vertebrae. The risk factors for new VCFs after PVP reported thus far remain controversial. These risk factors have neither been well identified or summarized. This systematic review was performed to identify the risk factors for new VCFs after PVP. Methods. Noninterventional studies evaluating the risk factors for new VCFs of patients with osteoporosis after PVP were searched in MEDLINE, EMBASE, ScienceDirect, and OVID databases (all up to November 2012). Only observational studies with eligible data were included. Quality of included studies was assessed by a modified quality assessment tool, which was previously designed for observational study. The effects of studies were combined with the study quality score using a model of best-evidence synthesis. Results. Twenty-four observational studies involving 3789 patients were included. These articles were published between 2004 and 2012. According to the quality assessment criteria for included studies, 8 studies were deemed as high-quality studies, 6 as moderate-quality studies, and 10 as low-quality studies. There were strong evidences of 3 risk factors, including lower bone mineral density, lower body mass index, intradiscal cement leakage, and vertebral height restoration. We also identified 6 moderate-evidence factors including lower body mass index, number of pre-existing vertebral fractures, thoracolumbar junction in initial VCFs, cement distraction, older age, and number of treated vertebrae. Thirteen factors were classified into the limited-evidence risk factors. Conclusion. Although there is no conclusive evidence for new VCFs of patients with osteoporosis after PVP procedure, these data provide evidence to guide the surgeon and develop optimal preventions for new VCFs after PVP. Special attention should be paid to the 3 strong-evidence risk factors. Further studies were still required to evaluate the effects of the earlier mentioned risk factors. Level of Evidence: 2

Open reduction and internal fixation versus external fixation for unstable distal radial fractures: A meta-analysis

PURPOSE To compare the clinical outcomes of open reduction and internal fixation (ORIF) versus the ones of closed reduction and external fixation (EF) in the treatment of distal radial fractures. METHODS We performed a meta-analysis of randomized controlled trials that compared the clinical results of ORIF to EF in the treatment of distal radial fractures. A systemic retrieve from PubMed, EMBASE, OVID and Cochrane Collaboration CENTRAL database resulted in 11 studies with 824 patients. We thus performed data synthesis using RevMan (version 5.1). RESULTS Superior statistical differences were observed for DASH scores (at 3, 6 and 12 months follow-up) grip strength (at 3 months follow-up), volar tilt (at 12 months follow-up), flexion and supination (at 3 months follow-up), and extension (at 3 and 6 months follow-up) in ORIF patients group, compared with those in EF group. We also found a significantly higher risk of infection associated with EF. There was no significant difference in the incidence of malunion and median nerve dysfunction. CONCLUSION Regarding surgical fixation of unstable distal radius fractures, ORIF yields significantly better subjective outcome (DASH scores) the first year after operation, restoration of anatomic volar tilt, and forearm flexion and extension at the end of the follow-up period. However, EF results in higher incidence of infection compared to ORIF. ORIF is equal to EF for either grip strength, or range of motion of the injured wrist, or incidence of malunion or median nerve dysfunction at the end of the follow-up period. LEVEL OF EVIDENCE Level II. Therapeutic study.

A methodological systematic review of early versus late stabilization of thoracolumbar spine fractures

ObjectiveThe optimal timing of stabilization in patients with traumatic thoracolumbar fractures remains controversial. There is currently a lack of consensus on the timing of surgical stabilization, which is limited by the reality that a randomized controlled trial to evaluate early versus late stabilization is difficult to perform. Therefore, the objective of this study was to determine the benefits, safety and costs of early stabilization compared with late stabilization using data available in the current literature.MethodsAn electronic literature search was performed in Medline, Embase, Cochrane Database of Systematic Reviews, and Cochrane Central Register of Controlled Trials for relevant studies evaluating the timing of surgery in patients with thoracolumbar fractures. Two reviewers independently analyzed and selected each study on the basis of the eligibility criteria. The quality of the included studies was assessed using the Grading of Recommendations Assessment, Development, and Evaluation system (GRADE). Any disagreements were resolved by consensus.ResultsTen studies involving 2,512 subjects were identified. These studies demonstrated that early stabilization shortened the hospital length of stay, intensive care unit length of stay, ventilator days and reduced morbidity and hospital expenses for patients with thoracic fractures. However, reduced morbidity and hospital expenses were not observed with stabilization of lumbar fractures. Owing to the very low level of evidence, no conclusion could be made regarding the effect of early stabilization on mortality.ConclusionsWe could adhere to the recommendation that patients with traumatic thoracolumbar fractures should undergo early stabilization, which may reduce the hospital length of stay, intensive care unit length of stay, ventilator days, morbidity and hospital expenses, particularly when the thoracic spine is involved. Individual patient characteristics should be concerned carefully. However, the definite conclusion cannot be made due to the heterogeneity of the included studies and low level of evidence. Further prospective studies are required to confirm whether there are benefits to early stabilization compared with late stabilization.

Dose intraarticular steroid injection increase the rate of infection in subsequent arthroplasty: grading the evidence through a meta-analysis

BackgroundIntraarticular steroid injections are widely used in joint arthritis. However, the data regarding an association between an increased risk for arthroplasty infection after an intraarticular steroid injection are still conflicting. We conducted a meta-analysis to evaluate the evidence from relevant studies that examine the relation between intraarticular steroid injections and infection rates in subsequent joint arthroplasty and to develop GRADE based recommendations for using the steroid before arthroplasty.MethodsA systematic search of all studies published through August 2014 was conducted using the MEDLINE, EMBASE, OVID, ScienceDirect and Cochrane CENTRAL databases. The relevant studies that examined the relation between intraarticular steroid injections and infection rates in subsequent joint arthroplasty were identified. Demographic characteristics, infection rates and clinical outcomes were manually extracted from all of the selected studies. The evidence quality levels and recommendations were assessed using the GRADE system.ResultsEight studies looking at hip and knee arthroplasties were included. Meta-analysis showed that patients with steroid injection before arthroplasty had a higher deep infection rate than patients without steroid injection (OR = 2.13, 95% CI 1.02-4.45), but no significant effect on superficial infection rate (OR = 1.75, 95% CI 0.74-4.16). The overall GRADE system evidence quality was very low, which lowers our confidence in their recommendations.ConclusionsIntraarticular steroid injections may lead to increased deep infection rates of subsequent joint arthroplasty but not the superficial infection rates. Due to the poor quality of the evidence currently available, further studies are still required.

Use of anti-granulocyte scintigraphy with 99mTc-labeled monoclonal antibodies for the diagnosis of periprosthetic infection in patients after total joint arthroplasty: a diagnostic meta-analysis.

The accurate diagnosis of periprosthetic joint infections (PJI) is crucial for therapy and the prevention of complications. No diagnostic test of PJI is 100% accurate. The aim of this study was to assess the use of anti-granulocyte scintigraphy using 99 mTc-labeled monoclonal antibodies to diagnose PJI after total joint arthroplasty. A systematic search of all relevant studies published through January 2013 was conducted using the MEDLINE, EMBASE, OVID, and ScienceDirect databases. Observational studies that assessed the accuracy of the anti-granulocyte scintigraphy with monoclonal antibodies or antibody fragments labeled with technetium 99 m in diagnosis for PJI and provided data on specificity and sensitivity were identified. Standard methods recommended for meta-analysis of diagnostic accuracy were used. Nineteen studies were eligible for inclusion. The results demonstrated that the area under the summary receiver operator curve was 0.88, and the diagnostic accuracy (Q*) was 0.81. Additionally, the diagnostic odds ratio (DOR) was 18.76 with a corresponding 95% confidence interval of 10.45–33.68. The pooled sensitivity and specificity of the diagnostic method for the diagnosis of PJI were 83% and 79%, respectively, while the pooled positive likelihood ratio (PLR) was 3.56, and the negative likelihood ratio (NLR) was 0.26. Anti-granulocyte scintigraphy using 99 mTc-labeled monoclonal antibodies has a reasonable role in the diagnosis of PJI after total joint arthroplasty. Due to the limitations of the present meta-analysis, additional high-quality original studies are required to confirm the predictive value.

Evaluation of the stress distribution change at the adjacent facet joints after lumbar fusion surgery: a biomechanical study.

Spinal fusion surgery has been widely applied in clinical treatment, and the spinal fusion rate has improved markedly. However, its postoperative complications, especially adjacent segment degeneration, have increasingly attracted the attention of spinal surgeons. The most common pathological condition at adjacent segments is hypertrophic degenerative arthritis of the facet joint. To study the stress distribution changes at the adjacent facet joint after lumbar fusion with pedicle screw fixation, human cadaver lumbar spines were used in the present study, and electrical resistance strain gauges were attached on L1–L4 articular processes parallel or perpendicular to the articular surface of facet joints. Subsequently, electrical resistance strain gauge data were measured using anYJ-33 static resistance strain indicator with three types of models: the intact model, the laminectomy model, and the fusion model with pedicle screw fixation. The strain changes in the measurement sites indirectly reflect the stress changes. Significant differences in strain were observed between the normal and laminectomy state at all facet joints. Significant differences in strain were observed between the normal and the pedicle screw fixation fusion state at the L1/2 and L3/4 facet joints. The increased stress on the facet joints after lumbar fusion with pedicle screw fixation may be the cause of adjacent segment degeneration.