[Show abstract][Hide abstract] ABSTRACT: Study Design Systematic review. Clinical Questions (1) What is the comparative efficacy of unilateral instrumentation compared with bilateral instrumentation in spine surgery? (2) What is the safety of unilateral instrumentation compared with bilateral instrumentation in spine surgery? Methods Electronic databases and reference lists of key articles were searched up to September 30, 2014, to identify studies reporting the comparative efficacy and safety of unilateral versus bilateral instrumentation in spine surgery. Studies including recombinant human bone morphogenetic protein 2 as adjunct therapy and those with follow-up of less than 2 years were excluded. Results Ten randomized controlled trials met the inclusion criteria: five compared unilateral with bilateral instrumentation using open transforaminal or posterior lumbar interbody fusion (TLIF/PLIF), one used open posterolateral fusion, and four used minimally invasive TLIF/PLIF. There were no significant differences between unilateral and bilateral screw instrumentation with respect to nonunion, low back or leg pain scores, Oswestry Disability Index, reoperation, or complications. Conclusions The existing literature does not identify significant differences in clinical outcomes, union rates, and complications when unilateral instrumentation is used for degenerative pathologic conditions in the lumbar spine. The majority of published reports involve single-level lumbar unilateral instrumentation.
Global Spine Journal 06/2015; 5(3):185-94. DOI:10.1055/s-0035-1552986
[Show abstract][Hide abstract] ABSTRACT: Study Design Systematic review. Clinical Questions (1) Is autologous local bone (LB) graft as safe and effective as iliac crest bone graft (ICBG) in lumbar spine fusion? (2) In lumbar fusion using ICBG, does a single-incision midline approach reduce postoperative iliac crest pain compared with a two-incision traditional approach? Methods Electronic databases and reference lists of key articles were searched up to October 2014 to identify studies reporting the comparative efficacy and safety of ICBG versus LB graft or comparing ICBG harvest site for use in lumbar spine surgery. Studies including allograft, synthetic bone, or growth factors in addition to ICBG and those with less than 80% of patients with degenerative disease in the lumbar spine were excluded. Two independent reviewers assessed the level of the evidence quality using the Grades of Recommendation Assessment, Development and Evaluation criteria, and disagreements were resolved by consensus. Results Seven studies were identified as using ICBG fusion for degenerative disease in the lumbar spine. There were no differences in the fusion, leg pain, low back pain, or functional outcomes between patients receiving LB versus ICBG. There was a higher incidence of donor site pain and sensory loss in patients receiving ICBG, with no donor site complications attributed to LB. Compared with patients with the graft harvested through the two-incision traditional approach, patients with the graft harvested through the single-incision midline approach had lower mean pain scores over the iliac crest, with a higher proportion reporting no iliac crest tenderness. In patients with ICBG harvested through the single-incision midline approach on either the right or the left side of the ilium, only 36% of the patients were able to correctly identify the side when asked whether they knew which iliac crest was harvested. Only 19% of the patients with ICBG harvested through the single-incision midline approach on either the right or the left side of the ilium reported pain that was concordant with the side that was actually harvested. Conclusions LB is as safe and efficacious as ICBG for instrumented fusion in the lumbar spine to treat degenerative disease. When ICBG is used, graft harvest through the single-incision midline approach reduces postoperative iliac crest pain compared with a two-incision approach.
Global Spine Journal 06/2015; 5(3):195-206. DOI:10.1055/s-0035-1552985
[Show abstract][Hide abstract] ABSTRACT: Study design:
To identify cost-effective treatment strategies for lumbar spine degenerative diseases.
Summary of background data:
There is a paucity of literature assisting physicians and society regarding the cost-efficiency of management of lumbar spine conditions. Limited articles on selective operative and nonoperative therapies have been published for a variety of lumbar conditions.
A systematic search of PubMed, EMBASE, the Cochrane Collaboration data base, University of York, Centre for Reviews and Dissemination (National Health Services Economic Evaluation Database and health technology assessment), and the Tufts CEA Registry was conducted through December 16, 2013. Three specific questions were addressed for adult patients: (1) What is the evidence that surgery is cost-effective compared with nonsurgical management for lumbar degenerative spondylolisthesis or stenosis? (2) What is the evidence that fusion is cost-effective compared with no fusion for degenerative spondylolisthesis or stenosis? and (3) What is the evidence that instrumentation is cost-effective compared with none for degenerative spondylolisthesis? The Quality of Health Economic Studies instrument was used to provide an initial basis for critical appraisal of included economic studies. Articles were further refined with individual review based on inclusion/exclusion criteria.
Initial search resulted in 122 potentially relevant citations, 115 of which were excluded at title and abstract levels and 3 at full-text reviews, leaving 5 for analysis. No non-English language text met inclusion/exclusion criteria. All studies illustrated a clinical benefit of surgical treatment as measured by quality-adjusted life year (0.11-8.05). Surgical treatments had a greater financial cost than nonoperative care ($5883-$26,035). Incremental cost-effectiveness ratio calculations noted operative treatment over nonoperative treatment for spondylolisthesis ($59,487-$115,600) per quality-adjusted life year. However, cost for patients without spondylolisthesis varied greatly from nonoperative treat dominating to $77,600 per quality-adjusted life year favoring surgery. Because the articles had heterogeneous methods and patient population, conclusion differed greatly on cost assessment.
Limited quality data exist on cost-effective treatment of degenerative lumbar spinal conditions, despite more recent interest related to this topic. It is important that future research efforts focus on constructing higher quality trials in this area to help determine the most cost-effective care.
Level of evidence:
[Show abstract][Hide abstract] ABSTRACT: Study Design Systematic review.
Clinical Questions Compared with no stimulation, does electrical stimulation promote bone fusion after lumbar spinal fusion procedures? Does the effect differ based on the type of electrical stimulation used?
Methods Electronic databases and reference lists of key articles were searched up to October 15, 2013, to identify randomized controlled trials (RCTs) comparing the effect of electrical stimulation to no electrical stimulation on fusion rates after lumbar spinal fusion for the treatment of degenerative disease. Two independent reviewers assessed the strength of evidence using the Grades of Recommendation Assessment, Development and Evaluation (GRADE) criteria.
Results Six RCTs met the inclusion criteria. The following types of electrical stimulation were investigated: direct current (three studies), pulsed electromagnetic field (three studies), and capacitive coupling (one study). The control groups consisted of no stimulation (two studies) or placebo (four studies). Marked heterogeneity in study populations, characteristics, and design prevented a meta-analysis. Regardless of the type of electrical stimulation used, cumulative incidences of fusion varied widely across the RCTs, ranging from 35.4 to 90.6% in the intervention groups and from 33.3 to 81.9% in the control groups across 9 to 24 months of follow-up. Similarly, when stratified by the type of electrical stimulation used, fusion outcomes from individual studies varied, leading to inconsistent and conflicting results.
Conclusion Given the inconsistency in study results, possibly due to heterogeneity in study populations/characteristics and quality, we are unable to conclude that electrical stimulation results in better fusion outcomes compared with no stimulation. The overall strength of evidence for the conclusions is low.
[Show abstract][Hide abstract] ABSTRACT: Study Design Systematic review.
Clinical Question What is the prevalence of incidental magnetic resonance imaging (MRI) findings of the spine in asymptomatic pediatric patients?
Methods Electronic databases and reference lists of key articles were searched up to December 15, 2013, to identify studies reporting the incidence or prevalence of incidental findings on MRI in asymptomatic pediatric patients. Athletes or children with a known history of trauma, infection, or congenital abnormalities were excluded.
Results Seven publications, one prospective cohort, and six cross-sectional studies met the inclusion criteria. The most commonly reported findings on MRI were disc-related and included degenerative disc disease (seven studies, prevalence 19.6%), disc herniation/protrusion (four studies, 2.9%), disc height/narrowed disc space (two studies, 33.7%), and endplate changes (two studies, 5.3%). Other disc-related findings, reported by one study each, included bulging disc, abnormal nucleus shape, annular tear, high intensity zone, and nerve root compression, with prevalences ranging from 4.5 to 51.6%. Spondylolisthesis and spondylolysis were reported by one study each with a prevalence of 2.3 and 0%, respectively. Other findings reported included tumors and infections (one study, 0% for both) and Scheuermann-type changes (one study, 7.7%).
Conclusions The prevalence of positive MRI findings in the asymptomatic pediatric population is higher than previously assumed, particularly in regard to disc morphology, highlighting the importance of correlating the history and physical examination to the MRI findings to avoid misdiagnosis or over-treatment in the pediatric population.
[Show abstract][Hide abstract] ABSTRACT: Study Design Systematic review.
Study Rationale The purpose of this review is to further define the published literature with respect to vertebral artery (VA) anomaly and injury in patients with degenerative cervical spinal conditions.
Objectives In adult patients with cervical spine or degenerative cervical spine disorders receiving cervical spine surgery, what is the incidence of VA injury, and among resulting VA injuries, which treatments result in a successful outcome and what percent are successfully repaired?
Materials and Methods A systematic review of pertinent articles published up to April 2013. Studies involving traumatic onset, fracture, infection, deformity or congenital abnormality, instability, inflammatory spinal diseases, or neoplasms were excluded. Two independent reviewers assessed the level of evidence quality using the Grades of Recommendation Assessment, Development and Evaluation criteria; disagreements were resolved by consensus.
Results From a total of 72 possible citations, the following met our inclusion criteria and formed the basis for this report. Incidence of VA injuries ranged from 0.20 to 1.96%. None of the studies reported using preoperative imaging to identify anomalous or tortuous VA. Primary repair and ligation were the most effective in treating VA injuries.
Conclusion The incidence of VA injuries in degenerative cervical spinal surgery might be as high as 1.96% and is likely underreported. Direct surgical repair is the most effective treatment option. The most important preventative technique for VA injuries is preoperative magnetic resonance imaging or computed tomography angiographic imaging to detect VA anomalies. The overall strength of evidence for the conclusions is low.
[Show abstract][Hide abstract] ABSTRACT: Study Rationale Cerebral palsy (CP) is a group of nonprogressive syndromes of posture and motor impairment associated with lesions of the immature brain. Spastic quadriplegia is the most severe form with a high incidence of scoliosis, back pain, respiratory compromise, pelvic obliquity, and poor sitting balance. Surgical stabilization of the spine is an effective technique for correcting deformity and restoring sitting posture. The decision to operate in this group of patients is challenging.
Objectives The aim of this study is to determine the benefits of surgical correction of scoliosis in children with spastic quadriplegia, the adverse effects of this treatment, and what preoperative factors affect patient outcome after surgical correction.
Materials and Methods A systematic review was undertaken to identify studies describing benefits and adverse effects of surgery in spastic quadriplegia. Factors affecting patient outcome following surgical correction of scoliosis were assessed. Studies involving adults and nonspastic quadriplegia were excluded.
Results A total of 10 case series and 1 prospective and 3 retrospective cohort studies met inclusion criteria. There was significant variation in the overall risk of complications (range, 10.9−70.9%), mortality (range, 2.8−19%), respiratory/pulmonary complications (range, 26.9−57.1%), and infection (range, 2.5−56.8%). Factors associated with a worse outcome were a significant degree of thoracic kyphosis, days in the intensive care unit, and poor nutritional status.
Conclusion Caregivers report a high degree of satisfaction with scoliosis surgery for children with spastic quadriplegia. There is limited evidence of preoperative factors that can predict patient outcome after scoliosis. There is a need for well-designed prospective studies of scoliosis surgery in spastic quadriplegia.
[Show abstract][Hide abstract] ABSTRACT: Study Design Systematic review.
Study Rationale The surgical treatment of adult degenerative lumbar conditions remains controversial. Conventional techniques include posterior lumbar interbody fusion (PLIF) or transforaminal lumbar interbody fusion (TLIF). A new direct approach known as lumbar lateral interbody fusion (LLIF), or extreme lateral interbody fusion (XLIF®) or direct lateral interbody fusion (DLIF), has been introduced.
Objectives The objective of this article is to determine the comparative effectiveness and safety of LLIF, at one or more levels with or without instrumentation, versus PLIF or TLIF surgery in adults with lumbar degenerative conditions, and to determine which preoperative factors affect patient outcomes following LLIF surgery.
Materials and Methods A systematic review of the literature was performed using PubMed and bibliographies of key articles. Articles were reviewed by two independent reviewers based on predetermined inclusion and exclusion criteria. Each article was evaluated using a predefined quality rating scheme.
Results The search yielded 258 citations and the following met our inclusion criteria: three retrospective cohort studies (all using historical cohorts) (class of evidence [CoE] III) examining the comparative effectiveness and safety of LLIF/XLIF®/DLIF versus PLIF or TLIF surgery, and one prospective cohort study (CoE II) and two retrospective cohort studies (CoE III) assessing factors affecting patient outcome following LLIF. Patients in the LLIF group experienced less estimated blood loss and a lower mortality risk compared with the PLIF group. The number of levels treated and the preoperative diagnosis were significant predictors of perioperative or early complications in two studies.
Conclusion There is insufficient evidence of the comparative effectiveness of LLIF versus PLIF/TLIF surgery. There is low-quality evidence suggesting that LLIF surgery results in fewer complications or reoperations than PLIF/TLIF surgery. And there is insufficient evidence that any preoperative factors exist that predict patient outcome after LLIF surgery.
[Show abstract][Hide abstract] ABSTRACT: Lateral mass screw fixation with plates or rods has become the standard method of posterior cervical spine fixation and stabilization for a variety of surgical indications. Despite ubiquitous usage, the safety and efficacy of this technique have not yet been established sufficiently to permit "on-label" U.S. Food and Drug Administration approval for lateral mass screw fixation systems. The purpose of this study was to describe the safety profile and effectiveness of such systems when used in stabilizing the posterior cervical spine.
A systematic search was conducted in MEDLINE and the Cochrane Collaboration Library for articles published from January 1, 1980, to December 1, 2011. We included all articles evaluating safety and/or clinical outcomes in adult patients undergoing posterior cervical subaxial fusion utilizing lateral mass instrumentation with plates or rods for degenerative disease (spondylosis), trauma, deformity, inflammatory disease, and revision surgery that satisfied our a priori inclusion and exclusion criteria.
Twenty articles (two retrospective comparative studies and eighteen case series) satisfied the inclusion and exclusion criteria and were included. Both of the comparative studies involved comparison of lateral mass screw fixation with wiring and indicated that the risk of complications was comparable between treatments (range, 0% to 7.1% compared with 0% to 6.3%, respectively). In one study, the fusion rate reported in the screw fixation group (100%) was similar to that in the wiring group (97%). Complication risks following lateral mass screw fixation were low across the eighteen case series. Nerve root injury attributed to screw placement occurred in 1.0% (95% confidence interval, 0.3% to 1.6%) of patients. No cases of vertebral artery injury were reported. Instrumentation complications such as screw or rod pullout, screw or plate breakage, and screw loosening occurred in <1% of the screws inserted. Fusion was achieved in 97.0% of patients across nine case series.
The risks of complications were low and the fusion rate was high when lateral mass screw fixation was used in patients undergoing posterior cervical subaxial fusion. Nerve root injury attributed to screw placement occurred in only 1% of 1041 patients. No cases of vertebral artery injury were identified in 758 patients. Screw or rod pullout, screw or plate breakage, and screw loosening occurred in <1% of the screws inserted.
Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.
The Journal of Bone and Joint Surgery 12/2013; 95(23):2136-43. DOI:10.2106/JBJS.L.01522 · 5.28 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Study Design Systematic review. Study Rationale Numerous cervical laminoplasty techniques have been described but there are few studies that have compared these to determine the superiority of one over another. Clinical Questions The clinical questions include key question (KQ)1: In adults with cervical myelopathy from ossification of the posterior longitudinal ligament (OPLL) or spondylosis, what is the comparative effectiveness of open door cervical laminoplasty versus French door cervical laminoplasty? KQ2: In adults with cervical myelopathy from OPLL or spondylosis, are postoperative complications, including pain and infection, different for the use of miniplates versus the use of no plates following laminoplasty? KQ3: Do these results vary based on early active postoperative cervical motion? Materials and Methods A systematic review of the English-language literature was undertaken for articles published between 1970 and March 11, 2013. Electronic databases and reference lists of key articles were searched to identify studies evaluating (1) open door cervical laminoplasty and French door cervical laminoplasty and (2) the use of miniplates or no plates in cervical laminoplasty for the treatment of cervical spondylotic myelopathy or OPLL in adults. Studies involving traumatic onset, cervical fracture, infection, deformity, or neoplasms were excluded, as were noncomparative studies. Two independent reviewers (A.L.R., J.R.D.) assessed the level of evidence quality using the Grades of Recommendations Assessment, Development and Evaluation system, and disagreements were resolved by consensus. Results We identified three studies (one of class of evidence [CoE] II and two of CoE III) meeting our inclusion criteria comparing open door cervical laminoplasty with French door laminoplasty and two studies (one CoE II and one CoE III) comparing the use of miniplates with no plates. Data from one randomized controlled trial (RCT) and two retrospective cohort studies suggest no difference between treatment groups regarding improvement in myelopathy. One RCT reported significant improvement in axial pain and significantly higher short-form 36 scores in the French door laminoplasty treatment group. Overall, complications appear to be higher in the open door group than the French door group, although complete reporting of complications was poor in all studies. Overall, data from one RCT and one retrospective cohort study suggest that the incidence of complications (including reoperation, radiculopathy, and infection) is higher in the no plate treatment group compared with the miniplate group. One RCT reported greater pain as measured by the visual analog scale score in the no plate treatment group. There was no evidence available to assess the effect of early cervical motion for open door cervical laminoplasty compared with French door laminoplasty. Both studies comparing the use of miniplates and no plates reported early postoperative motion. Evidence from one RCT suggests that earlier postoperative cervical motion might reduce pain. Conclusion Data from three comparative studies are not sufficient to support the superiority of open door cervical laminoplasty or French door cervical laminoplasty. Data from two comparative studies are not sufficient to support the superiority of the use of miniplates or no plates following cervical laminoplasty. The overall strength of evidence to support any conclusions is low or insufficient. Thus, the debate continues while opportunity exists for the spine surgery community to resolve these issues with appropriately designed clinical studies.
[Show abstract][Hide abstract] ABSTRACT: Study Design. A narrative review.Objective. To provide a detailed description of the methods undertaken in the articles in this focus issue pertaining to cervical spondylotic myelopathy (CSM) and ossification of the posterior longitudinal ligament (OPLL) and to describe the process used to develop summary statements and clinical recommendations regarding factors associated with the mechanisms, diagnosis, progression and treatment of CSM and OPLL.Summary of Background Data. We present methods used in conducting the systematic, evidence-based reviews and development of expert panel summary statements and clinical recommendations of the mechanisms, diagnosis, progression and treatment of CSM and OPLL. Our intent is that clinicians will combine the information from these systematic reviews, narrative reviews, and primary research studies with an understanding of their own capacities and experience to better manage patients with CSM or OPLL and consider future research for the diagnosis and treatment of these diseases.Methods. For the systematic reviews, which make up the bulk of the studies in this focus issue, a systematic search and critical review of the English language literature was undertaken for articles published on the mechanisms, diagnosis, progression and treatment of CSM and OPLL. Articles were screened for relevance using a priori criteria, and relevant articles were critically reviewed. Whether an article was included for review depended on whether the study question was descriptive, one of therapy, or one of prognosis. The strength of evidence for the overall body of literature in each topic area was determined by 2 independent reviewers considering risk of bias, consistency, directness, and precision of results using a modification of the Grades of Recommendation Assessment, Development and Evaluation (GRADE) criteria. Disagreements were resolved by consensus. Findings from articles meeting inclusion criteria were summarized. From these summaries, summary statements or clinical recommendations were formulated among subject experts through a modified Delphi process using the GRADE approach. Methods for the two primary research studies and the narrative reviews are also reviewed.Results. Because of the nature of questions that needed to be addressed, not all studies in this focus issue were amenable to systematic review. As a result, this focus issue consists of several different article types, including one research protocol, two primary research studies, two narrative literature reviews, seven systematic reviews, and three articles that combine a systematic review component with either a narrative section (n = 2) or provider survey (n = 1). In general, the strength of evidence ratings ranged from insufficient to moderate. Summary statements or clinical recommendations were made according to available evidence and study type: 16 summary statements were made across 8 articles, and 17 clinical recommendations were made across 9 articles. Three articles had both summary statements and clinical recommendations, five had summary statements only, six had clinical recommendations only, and one (the research protocol) was not amenable to either.Conclusion. Systematic reviews, narrative reviews, and primary research studies were undertaken to understand the mechanisms, diagnosis, progression and treatment of CSM and OPLL and to provide summary statements and clinical recommendations. This article reports the methods used in the studies in this focus issue.Summary Statements. The objectives of this focus issue were met using a variety of manuscript and study designs, each of which has some unique methodological aspects associated with them. The reader should refer to the full article in this issue for additional details specific to that topic. The methods for systematic review follow accepted standards for rigor and, together with the application of GRADE, are intended to allow for transparency in the process for creating the clinical recommendation.
[Show abstract][Hide abstract] ABSTRACT: Study Design. Systematic Review.Objective. To answer the following three clinical questions: (1) What is the evidence supporting a heritable predisposition for cervical spondylotic myelopathy (CSM) and ossification of the posterior longitudinal ligament (OPLL)? (2) What specific genetic polymorphisms have been associated with CSM and OPLL? (3) What is the evidence supporting a genetic basis for predicting postoperative outcomes for CSM and OPLL patients?Summary of Background Data. OPLL and CSM are thought to be multifactorial conditions resulting from a combination of environmental and genetic factors.Methods. A systematic review of the English language literature was undertaken for articles published between 1980 and November 7, 2012. The strength of evidence was determined by two independent reviewers using the GRADE criteria for studies addressing the first question of heritability, and using the criteria set forth by the HuGENet Working Group in the Venice Interim Guidelines to address the last two questions of genetic association.Results. Of the 118 citations identified through the initial literature search, a total of 23 articles remained after application of inclusion/exclusion criteria. The three family association studies related to question #1 supported the principle of an inherited predisposition to CMS and OPLL however the strength of evidence supporting these findings was low. Within the 19 case control studies related to question #2, two SNPs (COL6A1/Intron 32(-29) and COL11A2/Intron 6(-4)) were observed at higher frequencies in OPLL cases as compared to controls in >1 study and may be associated with its development. There was insufficient evidence to support an association between CSM and any specific SNP or haplotype, or to support the association of specific gene alleles with post-operative CSM outcomes.Conclusion. Existing family studies provide support for the principle of an inherited predisposition to CSM and OPLL. Multiple studies support the association of 2 collagen gene related SNPs with OPLL, however there is insufficient evidence to support the association between CSM and any genetic polymorphism or to support a genetic predictor of surgical outcome.Statement #1: Existing family studies provide support for the principle of an inherited predisposition to CSM and OPLLStatement #2: Two SNPs related to the collagen 6A1 gene (COL6A1/Intron 32(-29)) and the collagen 11A2 gene (COL11A2/Intron 6(-4)) have been associated with OPLL in multiple studies and may be associated with its development.Statement #3: No statement can be made from the literature regarding the association of specific SNPs or haplotypes with CSM.Statement #4: No statement can be made from the literature regarding genetic predictors of surgical outcome in the context of OPLL or CSM.
[Show abstract][Hide abstract] ABSTRACT: Study Design. Systematic ReviewObjective. To conduct a systematic review investigating the evidence of (1) efficacy, effectiveness, and safety of nonoperative treatment for patients with cervical myelopathy, (2) whether the severity of myelopathy affects outcomes of nonoperative treatment, and (3) whether specific activities or minor injuries are associated with neurologic deterioration in patients with myelopathy or asymptomatic stenosis being treated nonoperatively.Summary of Background Data. Little is known about the appropriate role of nonoperative treatment in the management of cervical myelopathy, which is typically considered a surgical disorder.Methods. A systematic search was conducted in PubMed and the Cochrane Collaboration Library for articles published between January 1, 1956 and November 20, 2012. We included all articles that compared nonoperative treatments or observation to surgery in patients with cervical myelopathy or asymptomatic cervical cord compression to determine their effects on clinical outcomes, including myelopathy scales (JOA, Nurick), general health scores (SF36), and pain (neck and arm).. Nonoperative treatments included physical therapy, medications, injections, orthoses, and traction. We also searched for articles evaluating the effect of specific activities or minor trauma in neurologic outcomes. Case reports and studies with less than 10 patients in the exposure group were excluded.Results. Of 54 citations identified from our search, 5 studies reported in 6 articles met inclusion criteria. In one randomized controlled study, there was low evidence that nonoperative treatment may yield equivalent or better outcomes versus surgery in those with mild myelopathy. For moderate to severe myelopathy, nonoperative treatment had inferior outcomes versus surgery in two cohort studies, despite the fact that surgically treated patients were worse at baseline. There was insufficient evidence to determine whether specific activities or minor trauma are risk factors for neurologic deterioration in those with myelopathy or asymptomatic cord compression.Conclusion. There is a paucity of evidence for nonoperative treatment of cervical myelopathy, and further studies are needed to more definitively determine its role. In particular for the patient with milder degrees of myelopathy, randomized studies comparing nonoperative to surgical treatment would be particularly helpful, as would trials comparing specific types of nonoperative treatments to the natural history of myelopathy.Because myelopathy is known to be a typically progressive disorder and there is little evidence that nonoperative treatment halts or reverses its progression, we recommend not routinely prescribing nonoperative treatment as the primary modality in patients with moderate to severe myelopathy.Recommendation #2: If there is a role for nonoperative treatment as a primary treatment modality, it may be in the patient with mild myelopathy. However, it is not clear which specific forms of nonoperative treatment provide any benefit over the natural history. If nonoperative treatment is selected, we suggest care be taken to observe for neurological deterioration.Recommendation #3: In those with asymptomatic spondylotic cord compression but no clinical myelopathy, the available literature neither supports nor refutes the notion that minor trauma is a risk factor for neurologic deterioration. We suggest that patients should be counseled about this uncertainty.Recommendation #4: In those with a clinical diagnosis of CSM but no OPLL, the available studies did not specifically address the issue of neurologic deterioration secondary to minor trauma. However, in those with underlying OPLL, trauma may be more likely to cause worsening of existing myelopathy or even initiate symptoms in those who were previously asymptomatic. We suggest that patients be counseled about these possibilities.
[Show abstract][Hide abstract] ABSTRACT: Study Design: Systematic ReviewObjective: To determine if there are MRI characteristics in patients with cervical spondylotic myelopathy that affect treatment decisions or predict post-surgical outcomes or adverse events.Summary of Background Data: Although the role of MRI in confirming the clinical diagnosis of cervical spondylotic myelopathy and directing surgical management is well established, its potential value as a prognostic tool is largely unknown.Methods: A systematic search was conducted using PubMed and the Cochrane Collaboration Library for articles published between January 1, 1956 and November 20, 2012. The overall body of evidence with respect to each clinical question was determined on the basis of precepts outlined by the Grades of Recommendation Assessment, Development, and Evaluation (GRADE) working group and recommendations made by the Agency for Healthcare Research and Quality.Results: The initial search yielded 268 citations. Twenty publications met all inclusion criteria and were included in the review. Three of these assessed MRI predictors of clinical deterioration in the case of conservative treatment and 17 evaluated MRI anatomic or cord characteristics that could predict surgical outcome or adverse events. There is low evidence suggesting that a high SI grade on T2WI is not associated with patient deterioration during conservative treatment. High SI on T2WI, along with compression ratio and canal diameter were not important predictors of outcome. There is low evidence identifying number of high SI segments on T2WI, low SI on T1WI, combined T1/T2 SI and SI ratio as important negative predictors of surgical outcome.Conclusion: Based on this review and on low quality evidence, we have identified three important negative predictors of surgical outcome: number of high SI segments on T2WI, combined T1/T2 signal change and SI ratio.Recommendation #1: We suggest that when clinically feasible, surgeons rely on MRI to confirm the diagnosis of CSM and rely on clinical history and examination to determine progression and severity of disease.Overall Strength of Evidence: LowStrength of Recommendation: WeakRecommendation #2: T2 signal may be a useful prognostic indicator when used in combination with low SI change on T1WI, or as a ratio comparing compressed versus non-compressed segments, or as a ratio of T2 compared with T1WI. We suggest that if surgeons use MRI signal intensity to estimate the risk of a poor outcome following surgery, they use high SI change on T2WI in combination with other signal intensity parameters, and not in isolation.Overall Strength of Evidence: LowStrength of Recommendation: Weak.
[Show abstract][Hide abstract] ABSTRACT: Study Design. The present study is a combination of narrative and systematic review.Objective. Clinicians who deal with cervical spondylotic myelopathy (CSM) should be up-to-date with the emerging knowledge related to the cascade of pathobiological secondary events which take place under chronic cervical spinal cord compression. Moreover by performing a systematic review we aim to 1) describe the natural history and 2) determine potential risk factors that affect the progression of CSM.Summary of Background Data. The pathophysiology, natural history as well as the factors associated with clinical deterioration have not been fully described in CSM.Methods. For the first part of the study, a literature review was performed. To answer the key questions 1 and 2 of the second goal, a systematic search was conducted in PubMed and the Cochrane Collaboration Library for articles published between January 1, 1956 and November 7, 2012. We included all articles that described the progression and outcomes of CSM for which no surgical intervention was given.Results. By performing a narrative literature review we found that the assumption that acute traumatic spinal cord injury (SCI) and CSM share a similar series of cellular and molecular secondary injury events was made in the past. However, recent advances in basic research have shown that the chronic mechanical compression results in secondary injury mechanisms which have distinct characteristics regarding the nature and the temporal profile compared to those of SCI. For the purpose of the systematic review, ten studies yielding 16 publications met inclusion criteria for key questions 2 and 3. Moderate strength evidence related to the natural history of CSM suggests that 20 to 60% of patients will deteriorate neurologically over time without surgical intervention. Finally, there is low strength evidence indicating that the area of circumferential compression is associated with deteriorating neurological symptoms.Conclusion. CSM has unique pathobiological mechanisms which mainly remain unexplored. Although the natural history of CSM can be mixed, surgical intervention eliminates the chances of the neurological deterioration.Recommendation: Evidence concerning the natural history of CSM suggests that 20 to 60% of patients will deteriorate neurologically over time without surgical intervention. Therefore, we recommend that patients with mild CSM be counseled regarding the natural history of CSM and have the option of surgical decompression explained.Overall Strength of Evidence: moderateStrength of Recommendation: StrongSummary Statements: Chronic compression of the spinal cord results in progressive neural cell loss related to secondary mechanisms including apoptosis, neuro-inflammation, and vascular disruption.
[Show abstract][Hide abstract] ABSTRACT: Study Design Systematic review. Study Rationale To seek out and assess the best quality evidence available comparing opening wedge osteotomy (OWO) and closing wedge osteotomy (CWO) in patients with ankylosing spondylitis to determine whether their results differ with regard to several different subjective and objective outcome measures. Objective The aim of this study is to determine whether there is a difference in subjective and objective outcomes when comparing CWO and OWO in patients with ankylosing spondylitis suffering from clinically significant thoracolumbar kyphosis with respect to quality-of-life assessments, complication risks, and the amount of correction of the spine achieved at follow-up. Methods A systematic review was undertaken of articles published up to July 2012. Electronic databases and reference lists of key articles were searched to identify studies comparing effectiveness and safety outcomes between adult patients with ankylosing spondylitis who received closing wedge versus opening wedge osteotomies. Studies that included pediatric patients, polysegmental osteotomies, or revision procedures were excluded. Two independent reviewers assessed the strength of evidence using the GRADE criteria and disagreements were resolved by consensus. Results From a total of 67 possible citations, 4 retrospective cohorts (class of evidence III) met our inclusion criteria and form the basis for this report. No differences in Oswestry Disability Index, visual analog scale for pain, Scoliosis Research Society (SRS)-24 score, SRS-22 score, and patient satisfaction were reported between the closing and opening wedge groups across two studies. Regarding radiological outcomes following closing versus opening osteotomies, mean change in sagittal vertical axis ranged from 8.9 to 10.8 cm and 8.0 to 10.9 cm, respectively, across three studies; mean change in lumbar lordosis ranged from 36 to 47 degrees and 19 to 41 degrees across four studies; and mean change in global kyphosis ranged from 38 to 40 degrees and 28 to 35 degrees across two studies. Across all studies, overall complication risks ranged from 0 to 16.7% following CWO and from 0 to 23.6% following OWO. Conclusion No statistically significant differences were seen in patient-reported or radiographic outcomes between CWO and OWO in any study. The risks of dural tear, neurological injury, and reoperation were similar between groups. Blood loss was greater in the closing wedge compared with the opening wedge group, while the risk of paralytic ileus was less. The overall strength of evidence for the conclusions is low.