John G. DeVine

Avoiding wrong site surgery: a systematic review.

Study Design. Systematic review. Objective. To report the incidence and causes of wrong site surgery and determine what preoperative measures are effective in preventing wrong site surgery. Summary of Background Data. From 1995 to 2005, the Joint Commission (JC) sentinel event statistics database ranked wrong site surgery as the second most frequently reported event with 455 of 3548 sentinel events (12.8%). Although the event seems to be rare, the incidence of these complications has been difficult to measure and quantify. The implications for wrong site surgery go beyond the effects to the patient. Such an event has profound medical, legal, social, and emotional implications. Methods. A systematic review of the English language literature was undertaken for articles published between 1990 and December 2008. Electronic databases and reference lists of key articles were searched to identify the articles defining wrong site surgery and reporting wrong site events. Two independent reviewers assessed the level of evidence quality using the Grading of Recommendations Assessment, Development, and Evaluation criteria and disagreements were resolved by consensus. Results. The estimated rate of wrong site surgery varies widely ranging from 0.09 to 4.5 per 10,000 surgeries performed. There is no literature to substantiate the effectiveness of the current JC Universal Protocol in decreasing the rate of wrong site, wrong level surgery. Conclusion. Wrong site surgery may be preventable. We suggest that the North American Spine Society and JC checklists are insufficient on their own to minimize this complication. Therefore, in addition to these protocols, we recommend intraoperative imaging after exposureand marking of a fixed anatomic structure. This imaging should be compared with routine preoperative studies to determine the correct site for spine surgery.

Evaluating common outcomes for measuring treatment success for chronic low back pain

Study Design. Systematic review. Objective. To identify, describe, and evaluate common outcome measures in patients with chronic low back pain (CLBP). Summary of Background Data. The treatment of CLBP has been associated with multiple clinical challenges. Further complicating this is the myriad of outcome scores used to assess treatment of CLBP. These scores have been used to examine different domains of patient satisfaction and quality of life in the literature. Critical assessment of the frequency, parity, and the quality of these outcomes are essential to improve our understanding of CLBP. Methods. A systematic review of the English-language literature was undertaken for articles published from January 2001 through December 31, 2010. Electronic databases and reference lists of key articles were searched to identify measures used to evaluate outcomes in six different domains in patients with CLBP. The titles and abstracts of the peer-reviewed literature of LBP were searched to determine which of these measures were most commonly reported in the literature and which have been validated in populations with CLBP. Results. We identified 75 outcome measures cited to evaluate CLBP. Twenty-nine of these outcome measures were excluded because of only a single citation leaving 46 measures for the evaluation. The most commonly used functional outcomes were the Oswestry Disability Index, Roland Morris Disability Index, and range of motion. For pain, the Numeric Pain Rating Scale, Brief Pain Inventory, Pain Disability Index, McGill Pain Questionnaire, and visual analog scale were most commonly cited. For psychosocial function, the Fear Avoidance Beliefs Questionnaire, Tampa Scale for Kinesiophobia, and Beck Depression Inventory were most commonly used. For generic quality of life, short form 36, Nottingham Health Profile, short form 12, and Sickness Impact Profile were the most common measures. For objective measures, the work status/return to work, complications or adverse events, and medications used were the most commonly cited. For preference-based measures, the Euro-Quol 5 dimensions and short form 6 dimensions were most commonly cited. The validity, reliability, responsiveness, universality, and potential proprietary requirements are summarized for each. Conclusion. Outcome measures should be routinely assessed in patients with CLBP. The choice of appropriate outcome measure should be influenced by the study objectives and design, as well as properties of the particular measure within the context of CLBP. Clinical Recommendations. Recommendation 1: When selecting the appropriate outcome measures for clinical or research purposes, consider domains that best measure what are most important to patients. Measures that are valid, reliable, and responsive to change should be considered first. Other considerations include the number of items required (especially in the context of multiple measures), whether the measure is validated in the relevant language, and the associated costs or fees. Strength: Strong Recommendation 2: Domains of greatest importance include pain, function, and quality of life. If cost utilization is a priority, then preference-based measures should be considered. For pain, we recommend the VAS and NRPS because of their ease of administration and responsiveness. For function, we recommend the ODI and RMDQ. The SF-36 and its shorter versions are most commonly used and should be considered if quality of life is important. If cost utility is important, consider the EQ-5D or SF-6D. Psychosocial tests are best used as screening tools prior to surgery because of their lack of responsiveness. Complications should always be assessed as a standard of clinical practice. Return to work and medication use are complicated outcome measures and not recommended unless the specific study question is focused on these domains. Consider staff and patient burden when prioritizing ones battery of measures.

The indications for interbody fusion cages in the treatment of spondylolisthesis: Analysis of 120 cases

Study Design. This study retrospectively examines outcomes of unilateral transforaminal lumbar interbody fusion (TLIF) with posterior fixation using anterior carbon fiber cages and 360° fusion in spondylolisthesis. Objectives. The goals were to examine the outcomes and perioperative complications of using anterior column support in the treatment of various types of spondylolisthesis. Summary of Background Data. In 2000, Brantigan et al reported the Brantigan interbody fusion cage used as a posterior lumbar interbody fusion in the US IDE clinical trial. This is the largest series to date of TLIF cages specifically used in the treatment of spondylolisthesis. Methods. A comprehensive long-term follow-up study was conducted to evaluate the fusion success and morbidity following implantation with an anterior column support and posterior pedicle screw fixation. The 120 patients with spondylolisthesis were comprised by 11 cases, dysplastic; 58 cases, degenerative; and 51 cases, isthmic-acquired spondylolisthesis. Anterior column support was either a rectangular carbon fiber/PEEK device or a cylindrical carbon fiber/PEEK device. Twenty-eight cases (23%) were revisions. Results. There were no pseudarthrosis, instrumentation failures, or significant subsidence at the TLIF level. The disc space height and foraminal height were restored as part of the surgical procedure. Disc height, as measured from the posterior edge of the superior vertebral body, increased from a mean of 5.6 mm before surgery to a mean of 9.3 mm after surgery. Although reduction of the slip was not the primary goal during the surgical procedure for the 120 cases with spondylolisthesis (isthmic-acquired = 51, degenerative = 58, and dysplastic = 11), the 23% slip reduction achieved at surgery was maintained at follow-up. Mean operative time was 143 ± 33 minutes (range, 70–255 minutes) for all cases. Mean blood loss was 724 ± 431 mL (range, 300–2,500 mL).There were seven incidental durotomies and three infections. One patient with Grade I degenerative spondylolisthesis required revision of the carbon fiber cage for posterior migration secondary to a traumatic event 3 months after surgery. Fusion success was 98% using the criteriaof Lenke for the posterior fusion and Brantigan and Steffee for the TLIF graft incorporation. Conclusions. Interbody cages in spondylolisthesis are useful to increase neuroforaminal height, to facilitate reduction, and to improve the chances of achieving a successful 360° fusion.

A prospective, randomized, controlled clinical investigation comparing PCM cervical disc arthroplasty with anterior cervical discectomy and fusion. 2-year results from the US FDA IDE clinical trial.

Study Design. Prospective, multicenter, randomized Food and Drug Administration approved investigational device exemption clinical trial. Objective. To evaluate the safety and effectiveness of the PCM Cervical Disc compared with anterior cervical discectomy and fusion (ACDF) in the treatment of patients with degenerative spondylosis and neurological symptoms at 1 level between C3–C4 and C7–T1. Summary of Background Data. Cervical disc arthroplasty in the treatment of symptomatic cervical spondylosis has been studied in other series. The PCM Cervical Disc is a nonconstrained motion-sparing alternative to ACDF. Methods. Patients 18 to 65 years of age with single-level symptomatic cervical spondylosis with radiculopathy and/or myelopathy unresponsive to nonoperative treatment were enrolled, including patients with prior nonadjacent or adjacent single-level fusions. The per-protocol patient sample at 2 years included 342 patients (189 PCM, 153 ACDF). Longitudinal outcomes were comparatively evaluated. Results. At 2 years postoperatively, clinical measures—neck and arm pain visual analogue scale, Neck Disability Index (NDI), SF-36, and neurological status—were significantly improved from preoperative baselines in both groups. Mean NDI score at 2 years was significantly lower in PCM group (P = 0.029). There were no statistical differences between groups in rates of surgery-related serious adverse events (5.6% PCM, 7.4% ACDF) or secondary surgical procedures (5.2% PCM, 5.4% ACDF). Patients with PCM reported lower dysphagia scores (8.8/100 vs. 12.1/100; P = 0.045) and higher patient satisfaction (82.8/100 vs. 81.4/100). Overall success, a composite endpoint including minimum 20% NDI improvement, no major complications, no neurological worsening, no secondary surgical procedures, and meeting radiographical criteria of motion for PCM and fusion for ACDF, was significantly greater in the PCM group (75.1% vs. 64.9%; P = 0.020). Conclusion. The treatment of symptomatic single-level cervical spondylosis with PCM achieves clinical outcomes that are at least equivalent to ACDF while maintaining motion. At 2 years, patients with PCM had lower NDI scores, statistically lower rate of prolonged dysphagia, greater patient satisfaction, and superior overall success. Level of Evidence: 1

Evaluating the Correlation and Responsiveness of Patient-reported Pain With Function and Quality-of-life Outcomes After Spine Surgery

Study Design. Systematic review. Objective. To determine the correlation of patient-reported pain with physical function and health-related quality of life (HRQoL) after spine surgery and to determine the responsiveness of pain, physical function, and HRQoL after spine surgery. Summary of Background Data. Several validated outcome instruments are available to assess the success of treatment for chronic low back pain. These patient-centered tools include measurements for pain based on numeric scales, validated condition-specific functional outcomes measures, and HRQoL outcomes measures. It is unclear whether these three types of patient-reported outcomes are measuring different constructs and whether all three should be measured after spine surgery. In addition, it is unclear which of these outcomes measures is most sensitive to change after spine surgery for low back pain. Methods. A systematic search was conducted in MEDLINE, EMBASE, and the Cochrane Collaboration Library for literature published through December 2010. The correlation between pain (visual analog scale, VAS), physical function (Oswestry Disability Index, ODI), and HRQoL (36-Item Short Form Health Survey [SF-36] and European Quality of Life [EQ-5D]) change scores was performed using the Spearman rank correlation coefficients. To compare the responsiveness of pain, function, and HRQoL scores after spine surgery, we calculated effect sizes by dividing change scores by the SD of the baseline scores. This standardized method allowed us to compare the responsiveness of each outcome measure directly and reported an effect size of 0.2 to 0.3 as a “small” effect, around 0.5 a “medium” effect and 0.8 to infinity, a “large” effect. To determine whether the differences in effect sizes measuring responsiveness were significantly different, we conducted a Wilcoxon signed-rank test between each of the three measurements of pain, function, and HRQoL scores when there was enough data to perform the test. Results. None of the correlations exceeded 0.70 using the Spearman rank correlation coefficients, suggesting that these outcomes are measuring different constructs. The strongest correlations were between the VAS back pain change scores and the SF-36 physical composite score change scores (&rgr; = 0.67) and VAS back pain change scores and ODI change scores (&rgr; = 0.69). The pooled mean effect sizes for the five studies that reported a pain measure and the ODI were 1.4 ± 0.57 and 1.1 ± 0.39, respectively. Both are considered “large” effect sizes. The pooled mean effect sizes for the three studies reporting the SF-36 physical and mental composite scores were 0.66 ± 0.39 and 0.54 ± 0.36, respectively. Both are considered “medium” effect sizes. The pooled mean effect sizes for the single studies reporting the EQ-5D and SF-36 total score were 0.78 ± 0.12 and 0.34 ± 0.21. These were “medium” and “small,” respectively. Conclusion. We observed little correlation between the change in pain and the change in HRQoL outcomes measures. The strongest correlation was between VAS pain and ODI but was still not considered strong (0.69). These findings suggest that these three outcomes (pain, function, and HRQoL) are measuring different constructs. With respect to responsiveness, VAS pain and ODI were the only outcomes measures that demonstrated a large effect after lumbar spine surgery. None of the HRQoL tools were as sensitive to the treatment. The EQ-5D, SF physical composite, and SF mental composite outcomes demonstrated a medium effect, while the SF-36 total score demonstrated a small effect. The responsive measure shows that the more specific the outcomes tool, the more sensitive the response. Clinical Recommendations. Recommendation 1: When surgically treating CLBP, we recommend administering both a VAS for pain and a condition-specific physical measure such as the ODI before and after surgical intervention as these outcomes are the most treatment specific and responsive to change. Strength of recommendation: Strong. Recommendation 2: When evaluating the surgical outcomes for CLBP in the clinical-research setting, we recommend selecting a shorter version for measuring general HRQoL (e.g., SF-12, EQ-5D) to minimize clinician and patient burden. Strength of recommendation: Strong.

Lower incidence of dysphagia with cervical arthroplasty compared with ACDF in a prospective randomized clinical trial.

Study Design The current study of 251 consecutive 1-level anterior cervical reconstructions was undertaken to compare the incidence of dysphagia between cervical disk replacement and conventional anterior cervical fusion and instrumentation. Objectives This is a report of 251 patients from 5 investigational centers in the Food and drug Administrations prospective, randomized porous-coated motion (PCM) trial using a validated dysphagia outcomes instrument. The dysphagia data for both PCM and anterior cervical diskectomy and fusion (ACDF) patients were reviewed from 5 centers to (1) compare the severity of dysphagia, (2) compare the postoperative incidence of dysphagia, and (3) to compare the resolution of perioperative dysphagia. Summary of Background Data Dysphagia and dysphonia after anterior surgical approaches to the cervical spine have been previously reported. The current prospective, randomized investigation quantifies clinical dysphagia based on 3 criteria-severity, incidence, and resolution—in a time-course evaluation. Methods Patients between 18 and 65 years with 1-level symptomatic cervical radiculopathy and/or myelopathy for progressive neurologic symptoms, were randomized to undergo anterior decompression and PCM arthroplasty (N=151) or ACDF (control) (N=100). Patients self-reported dysphagia severity using the Bazaz scale preoperatively and at follow-up. The Bazaz scale has 4 classes of severity based upon the problems with swallowing that the patient has with both liquids and solids. Results The Bazaz results demonstrate that although both the PCM and ACDF groups exhibited an initial postoperative problem with swallowing, the PCM group continued to improve with increasing time after implantation, whereas the ACDF only improved minimally. The PCM treatments indicated significantly lower incidence of dysphagia at 3 and 12 months postoperatively compared with ACDF controls (P<0.05). An increase in dysphagia severity at either the 6-week or 3-month follow-up visit was reported in 35 (42%) PCM and 29 (64%) ACDF subjects. Long-term resolution of these symptoms was noted in 74% (26/35) of the PCM subjects as compared with 41.4% (12/29) of the ACDF subjects (P=0.015). Conclusions In a prospective randomized clinical study the incidence of postoperative dysphagia and the long-term resolution of the dysphagia was greatly improved in the PCM group compared with the instrumented ACDF control group.

Vascular injury in elective anterior lumbosacral surgery.

Study Design. Systematic review. Objective. To document the incidence and consequences of vascular injury in lumbosacral surgery, to identify factors contributing to this injury, and to determine whether there are any effective measures to decrease the occurrence of vascular injury. Summary of Background Data. Anterior lumbosacral surgery encompasses all aspects of spine surgery, including trauma, deformity, and degenerative conditions. Although it has theoretical advantages, anterior lumbosacral surgery carries with it certain definite risks, one of the most critical of which is injury to the surrounding vasculature. It is important for both the patient and the surgeon to understand the risks, patterns, and outcomes of injury to the vascular structures associated with this surgery. Methods. A systematic review of the English-language literature was undertaken for articles published between January 1993 and December 2008. Electronic databases and reference lists of key articles were searched to identify published studies examining vascular injury in anterior lumbosacral surgery. Vascular injury was defined as any case in which a suture was required to control bleeding. Two independent reviewers assessed the strength of literature using the Grading of Recommendations Assessment, Development, and Evaluation criteria assessing quality, quantity, and consistency of results. Disagreements were resolved by consensus. Results. A total of 88 articles were initially screened, and 40 ultimately met the predetermined inclusion criteria. Vascular injuries after anterior lumbosacral surgeries were rare (<5%). Venous laceration was more common than arterial laceration, and most venous injuries occurred during retraction of the great vessels. In most cases, the overall clinical outcome after vascular injury was not adversely affected. L4–L5 exposure was associated with increased vascular injury in some studies but not others. Vascular injury occurred more frequently in laparoscopic compared with open anterior lumbar interbody fusion. Conclusion. Vascular injury in anterior lumbosacral surgery remains low, with reports being <5%. The consequences of injury seem rare, but may include thrombosis, pulmonary embolism, and prolonged hospitalization. Exposure and surgery at L4–L5 may be associated with a higher risk of injury than that at L5–S1, though the data are not consistent.

Cervical disc replacement in patients with and without previous adjacent level fusion surgery: A prospective study

Study Design. Prospective 6-center study. Objective. To evaluate outcomes of cervical disc replacement performed adjacent to a prior cervical fusion. Summary of Background Data. The use of disc replacement adjacent to a prior anterior cervical decompression and fusion (ACDF) is an attractive reconstructive option, obviating the need for a multilevel fusion. This study reports outcomes from patients with and without previous ACDF receiving the porous coated motion (PCM) artificial cervical disc in a United States Federal Drug Administration Investigational Device Exemption trials. Methods. Patients between ages of 18 and 65 with single-level cervical radiculopathy and/or myelopathy, unresponsive to at least 6 weeks of nonsurgical therapy, or experiencing progressive neurologic symptoms were enrolled. Clinical outcomes are compared for patients receiving a PCM disc at a level adjacent to a prior ACDF (“adjacent”) and those without having previously had fusion (“primary”). Results. 126 PCM patients were primary (mean age: 44.4 years.) and 26 patients had previous “adjacent level” fusion surgery (mean age: 46.4 years). Surgery time was similar in both groups (96 minutes and 98 minutes, respectively; P = 0.761), and mean blood loss was 76 mL and 66 mL in the 2 groups, respectively (P = 0.491). Clinical outcomes using Neck Disability Index and Visual Analog Scores neck and arm scores showed significant improvement after surgery and were similar between groups at all time points. Revision surgery occurred in 2 of 126 primary patients, and in 2 of 26 patients in the adjacent-to-fusion group. Conclusion. Although the level adjacent to a prior cervical fusion is subject to increased biomechanical forces, potentially leading to a higher risk of failure, the PCM disc was well tolerated in the short term. The early clinical results of disc replacement adjacent to a prior fusion are good and comparable to the outcomes after primary disc replacement surgery. However, in view of the small study population and short-term follow-up, continued study is mandatory.

The use of rhBMP in spine surgery: is there a cancer risk?

Abstract Study design: Systematic review. Study rationale: Some have noted several safety issues associated with the use of bone morphogenetic proteins (BMPs), including cancer risk, stating both BMP and their receptors had been isolated from human tumors. In addition, data presented to the US Food and Drug Administration (FDA) on the product AMPLIFY™ (rhBMP-2, 40 mg) revealed a higher number of cancers in the investigational group compared with the control. Objective: To independently review the cancer risk of rhBMP-2 use in spine fusion as published in the peer-reviewed literature and in the publicly available FDA data summaries. Methods: A systematic review of the literature was undertaken for articles published through January 2012. Pubmed, Cochrane, National Guideline Clearinghouse Databases as well as bibliographies of key articles were searched. Two independent reviewers revised articles. Inclusion and exclusion criteria were set and each article was subjected to a predefined quality-rating scheme. Results: Five published peer-reviewed studies and two FDA safety summaries reported the occurrence of cancer in patients treated with spinal fusion using rhBMP-2 or rhBMP-7. Cancer data for on-label use of rhBMP-2 (InFUSE™) were reported in the FDA data summary but not in one published pivotal study. The risk of cancer was same in both the rhBMP-2 and control groups, 0.7% after 24 months. Off-label use of rhBMP for posterolateral fusion (PLF) was associated with a slightly higher risk of cancer compared with controls in three randomized controlled trials and one poorly conducted retrospective cohort study at various follow-ups. In PLF the risk of cancer was 3.8% using 40 mg of BMP-2 compared with 0.9% in the control group. Two RCTs evaluating rhBMP-7 reported a cancer risk of 12.5% and 5.6% in the rhBMP-7 group compared with 8.3% and 0% in the control groups, respectively. The differences in these studies were not statistically significant; however, the sample sizes for these studies were small. Conclusions: Cancer risk with BMP-2 may be dose dependent, illustrating the need to continue to study this technology and obtain longer follow-up on patients currently enrolled in the FDA trials. Additionally, refined guidelines regarding the routine use of BMPs should be developed, taking into account the FDA summary data that is not routinely scrutinized by the practicing surgeon.

Jefferson fracture resulting in Collet-Sicard syndrome.

Study Design. A case report and review of the literature. Objective. To increase awareness of and add to the spectrum of injury that can result from Jefferson fractures, to suggest a possible mechanism of injury, and to give a brief review of pertinent facts regarding C1 burst fractures and the Collet-Sicard Syndrome. Summary of Background Data. To the author’s knowledge, this is the first reported case of a Jefferson fracture resulting in Collet-Sicard Syndrome. It represents only the second reported case of cranial nerve palsy caused by Jefferson fracture. Methods. A 56-year-old man sustained a C1 burst fracture in a rollover motor vehicle accident. Repeated neurologic examinations over the ensuing days revealed lesions of cranial nerves IX, X, XI, and XII on the left side. Results. Two weeks of traction, 10 weeks in a halo vest, and 2 weeks in a cervical collar resulted in adequate fracture healing and almost complete resolution of the patient’s neurologic symptoms. Conclusion. Although this is the first reported case of Collet-Sicard Syndrome caused by Jefferson fracture, the authors’ review of the literature suggests that cranial nerve injuries may go unrecognized in some patients with C1 burst fractures. The importance of a thorough neurologic examination, including examination of the cranial nerves, in all cases of cervical spine injury cannot be overemphasized.