Guideline summary review: an evidence-based clinical guideline for the diagnosis and treatment of low back pain.

BACKGROUND CONTEXT: The North American Spine Society's (NASS) Evidence Based Clinical Guideline for the Diagnosis and Treatment of Low Back Pain features evidence-based recommendations for diagnosing and treating adult patients with nonspecific low back pain. The guideline is intended to reflect contemporary treatment concepts for nonspecific low back pain as reflected in the highest quality clinical literature available on this subject as of February 2016. PURPOSE: The purpose of the guideline is to provide an evidence-based educational tool to assist spine specialists when making clinical decisions for adult patients with nonspecific low back pain. This article provides a brief summary of the evidence-based guideline recommendations for diagnosing and treating patients with this condition. STUDY DESIGN: This is a guideline summary review. METHODS: This guideline is the product of the Low Back Pain Work Group of NASS' Evidence-Based Clinical Guideline Development Committee. The methods used to develop this guideline are detailed in the complete guideline and technical report available on the NASS website. In brief, a multidisciplinary work group of spine care specialists convened to identify clinical questions to address in the guideline. The literature search strategy was developed in consultation with medical librarians. Upon completion of the systematic literature search, evidence relevant to the clinical questions posed in the guideline was reviewed. Work group members utilized NASS evidentiary table templates to summarize study conclusions, identify study strengths and weaknesses, and assign levels of evidence. Work group members participated in webcasts and in-person recommendation meetings to update and formulate evidence-based recommendations and incorporate expert opinion when necessary. The draft guideline was submitted to an internal and external peer review process and ultimately approved by the NASS Board of Directors. RESULTS: Eighty-two clinical questions were addressed, and the answers are summarized in this article. The respective recommendations were graded according to the levels of evidence of the supporting literature. CONCLUSIONS: The evidence-based clinical guideline has been created using techniques of evidence-based medicine and best available evidence to aid practitioners in the diagnosis and treatment of adult patients with nonspecific low back pain. The entire guideline document, including the evidentiary tables, literature search parameters, literature attrition flowchart, suggestions for future research, and all of the references, is available electronically on the NASS website at https://www.spine.org/ResearchClinicalCare/QualityImprovement/ClinicalGuidelines.aspx.

Thoracolumbar Vertebral Column Resection With Rectangular Endplate Cages Through a Posterior Approach: Surgical Techniques and Early Postoperative Outcomes.

BACKGROUND: Thoracolumbar pathology can result in compression of neural elements, instability, and deformity. Circumferential decompression with anterior column reconstruction is often required to restore biomechanical stability and minimize the risk of implant failure. OBJECTIVE: To assess the safety and viability of wide-footprint rectangular cages for vertebral column resection (VCR). METHODS: We performed VCR with wide-footprint rectangular endplate cages, which were designed for transthoracic or retroperitoneal approaches. We present our technique using a single-stage posterior approach. RESULTS: A total of 45 patients underwent VCR with rectangular endplate cages. Mean age was 58 yr. Diagnoses included 23 tumors (51%), 14 infections (31%), and 8 deformities (18%). VCRs were performed in 10 upper thoracic, 17 middle thoracic, 14 lower thoracic, and 4 lumbar levels. Twenty-four cases involved a single level VCR (53%) with 18 two-level (40%) and 3 three-level (7%) VCRs. Average procedure duration was 264 min with mean estimated blood loss of 1900 ml. Neurological outcomes were stable in 27 cases (60%), improved in 16 (36%), and worse in 2 (4%). There were 7 medical and 7 surgical complications in 11 patients. There were significant decreases in postoperative thoracic kyphosis (47° vs 35°, P = .022) and regional kyphosis (34° vs 10°, P < .001). There were 2 cases of cage subsidence due to intraoperative endplate violation, neither of which progressed on CT scan at 14 and 35 mo. CONCLUSION: Posterior VCR with rectangular footprint cages is safe and feasible. This provides improved biomechanical stability without the morbidity of a lateral transthoracic or retroperitoneal approach.

Cone Beam Intraoperative Computed Tomography-based Image Guidance for Minimally Invasive Transforaminal Interbody Fusion.

Transforaminal lumbar interbody fusion (TLIF) is commonly used for the treatment of spinal stenosis, degenerative disc disease, and spondylolisthesis. Minimally invasive surgery (MIS) approaches have been applied to this technique with an associated decrease in estimated blood loss (EBL), length of hospital stay, and infection rates, while preserving outcomes with traditional open surgery. Previous MIS TLIF techniques involve significant fluoroscopy that subjects the patient, surgeon, and operating room staff to non-trivial levels of radiation exposure, particularly for complex multi-level procedures. We present a technique that utilizes an intraoperative computed tomography (CT) scan to aid in placement of pedicle screws, followed by traditional fluoroscopy for confirmation of cage placement. Patients are positioned in the standard fashion and a reference arc is placed in the posterior superior iliac spine (PSIS) followed by intraoperative CT scan. This allows for image-guidance-based placement of pedicle screws through a one-inch skin incision on each side. Unlike traditional MIS-TLIF that requires significant fluoroscopic imaging during this stage, the operation can now be performed without any additional radiation exposure to the patient or operating room staff. After completion of the facetectomy and discectomy, final TLIF cage placement is confirmed with fluoroscopy. This technique has the potential to decrease operative time and minimize total radiation exposure.

Management of aortic injury during minimally invasive lateral lumbar interbody fusion.

PURPOSE: Minimally invasive lateral approaches to the lumbar spine allow for interbody fusion with good visualization of the disk space, minimal blood loss, and decreased length of stay. Major neurologic, vascular, and visceral complications are rare with this approach; however, the steps in management for severe vascular injuries are not well defined. We present a case report of aortic injury during lateral interbody fusion and discuss the use of endovascular repair. METHODS: This study is a case report of an intraoperative aortic injury. RESULTS: A 59-year-old male with ankylosing spondylitis suffered an acute L1 Chance fracture after mechanical fall. He was taken to the operating room for a T10-L4 posterior instrumented fusion followed by a minimally invasive L1-L2 lateral interbody fusion for anterior column support. During the discectomy, brisk arterial bleeding was encountered due to an aortic injury. The vascular surgery team expanded the incision in an attempt to control the bleeding but with limited success. The patient underwent intraoperative angiogram with placement of stent grafts at the level of the injury followed by completion of the interbody fusion. Despite the potentially catastrophic nature of this injury, the patient made a good recovery and was discharged home in stable condition with no new neurologic deficits. CONCLUSIONS: This case highlights the importance of immediate recognition and imaging of any potential vascular injury during minimally invasive lateral interbody fusion. Given the poor outcomes associated with attempted open repair, endovascular techniques provide a valuable tool for the treatment of these complex injuries with significantly less morbidity.

Radiation exposure with hybrid image-guidance-based minimally invasive transforaminal lumbar interbody fusion.

The transforaminal lumbar interbody fusion (TLIF) is used for the treatment of back and leg pain secondary to spinal stenosis, degenerative disc disease, and spondylolisthesis. Minimally invasive surgery (MIS) is associated with less estimated blood loss (EBL), decreased length of stay, lower infection rates, and similar outcomes compared to the traditional TLIF. Fluoroscopy time has been reported with MIS-TLIF, but there are limited data on specific radiation dosages. We performed a retrospective analysis of a prospectively acquired cohort of patients undergoing MIS-TLIF. A total of 50 patients were included. Mean age was 53 years with 60% women and mean BMI of 30 (range 21-41). Diagnoses were as follows: 45 stenosis (90%), 29 spondylolisthesis (58%), 5 facet cysts (10%), 3 scoliosis (6%), and 1 cauda equina syndrome (2%). A single level was fused in 33 cases (66%), two levels in 15 (30%), three levels in 2 (4%). Average cage height was 10 mm with mean EBL of 80 ml and operative time of 240 min. The average radiation doses from intraoperative CT scan and fluoroscopy were 35.3 and 26.5 mGy, respectively. Average CT scan and fluoroscopy times were 5.2 and 37.1 s, respectively, for a total of 42.2 s. Average length of stay was 3 days (range 1-7 days). Although these data represent a preliminary experience, by streamlining the timing of intraoperative CT scan and minimizing the amount of intraoperative fluoroscopy, this protocol has the potential for decreasing operative time and radiation exposure.

Circumferential fusion for degenerative lumbar spondylolisthesis complicated by distal junctional grade 4 spondylolisthesis in the sub-acute post-operative setting.

INTRODUCTION: Surgical management for lumbar stenosis is generally safe and provides significant improvements in pain, disability, and function. Successful lumbar decompression hinges on removing an appropriate amount of lamina and other compressive pathology in the lateral recess. Too little bony decompression can result in persistent pain and disability, while over resection of the pars and/or facets may jeopardize spinal stability. CASE REPORT: In this unique report, we present for the first time an acute iatrogenic grade 4 L5-S1 spondylolisthesis distal to a L3-5 laminectomy and circumferential instrumented fusion due to bilateral iatrogenic L5 pars fractures and its management and clinical outcomes after revision operation. The patient presented with worsening pain, neurologic compromise, and severe sagittal imbalance. The iatrogenic, high-grade spondylolisthesis was urgently addressed with a L5-S1 anterior lumbar interbody fusion and extension of posterior instrumentation to the pelvis, which resulted in considerable pain relief, resolution of neurologic deficits, and reconstitution of acceptable sagittal imbalance. CONCLUSION: All attempts during a lumbar decompression should be made to prevent iatrogenic pars fractures, as they may result in severe sagittal imbalance, neurologic compromise, and persistent disability. Iatrogenic, high-grade L5-S1 spondylolisthesis can be successfully treated with reduction using circumferential fusion of the lumbosacral junction.

Fatigue Failure in Extra-Articular Proximal Tibia Fractures: Locking Intramedullary Nail Versus Double Locking Plates-A Biomechanical Study.

OBJECTIVES: The goal of this study is to compare the fatigue strength of a locking intramedullary nail (LN) construct with a double locking plate (DLP) construct in comminuted proximal extra-articular tibia fractures. METHODS: Eight pairs of fresh frozen cadaveric tibias with low bone mineral density [age: 80 ± 7 (SD) years, T-score: -2.3 ± 1.2] were used. One tibia from each pair was fixed with LN, whereas the contralateral side was fixed with DLP for complex extra-articular multifragmentary metaphyseal fractures (simulating OTA 41-A3.3). Specimens were cyclically loaded under compression simulating single-leg stance by staircase method out to 260,000 cycles. Every 2500 cycles, localized gap displacements were measured with a 3D motion tracking system, and x-ray images of the proximal tibia were acquired. To allow for mechanical settling, initial metrics were calculated at 2500 cycles. The 2 groups were compared regarding initial construct stiffness, initial medial and lateral gap displacements, stiffness at 30,000 cycles, medial and lateral gap displacements at 30,000 cycles, failure load, number of cycles to failure, and failure mode. Failure metrics were reported for initial and catastrophic failures. RESULTS: DLP constructs exhibited higher initial stiffness and stiffness at 30,000 cycles compared with LN constructs (P < 0.03). There were no significant differences between groups for loads at failure or cycles to failure. CONCLUSIONS: For the fixation of extra-articular proximal tibia fractures, a LN provides a similar fatigue performance to double locked plates. The locked nail could be safely used for fixation of proximal tibia fractures with the advantage of limited extramedullary soft tissue damage.

Adult Spinal Deformity Correction with Multi-level Anterior Column Releases: Description of a New Surgical Technique and Literature Review.

STUDY DESIGN: Case series. OBJECTIVE: To evaluate radiographic and clinical outcomes of adults with spinal deformity treated with multilevel anterior column releases (ACR). SUMMARY OF BACKGROUND DATA: Pedicle subtraction osteotomy can be used effectively to correct spinal deformity; however, it is not without complications. ACR is an attractive alternative minimally invasive technique for spinal deformity correction, although few clinical reports on its clinical effectiveness exist. METHODS: Adults with spinal deformity who underwent multilevel ACRs (≥2) followed by open posterior instrumentation with a minimum 1-year follow-up were retrospectively reviewed. Deformity radiographic data and clinical outcomes, including the Oswestry Disability Index (ODI) and the EuroQol-5D were analyzed. RESULTS: Eight patients [7 female, 1 male; mean age 65 y (49-79 y)] met inclusion criteria. The mean follow-up was 18.4 months (12-28 mo). The average number of levels treated with an ACR per patient was 2.4 (2-3). There were no anterior approach-related complications. The average number of levels instrumented posteriorly was 8.1 (3-15). Six patients underwent Schwab type 1 posterior osteotomies (partial facetectomies). After the first anterior stage, there was a significant increase in the lumbar lordosis and significant decreases in the sagittal vertical axis, pelvic tilt, and lumbopelvic mismatch (P<0.05). After the second stage there was no significant change in the sagittal vertical axis, lumbar lordosis, pelvic tilt, or lumbopelvic mismatch relative to the values obtained after ACR. There was significantly less disability postoperatively [ODI: 15 (0-30)] compared with preoperatively [ODI: 46 (16-80)] (P<0.01). There was significant improvement in general health after operation, as assessed by the EuroQol-5D utility scores [preop: 0.44 (0.21-0.82) vs. postop: 0.71 (0.60-0.80)] (P=0.01). Back and leg visual analog scale pain scores improved significantly postoperatively. CONCLUSIONS: A staged approach using multilevel ACRs with open posterior instrumentation has an acceptable complication profile and provides excellent restoration of sagittal and coronal balance and pelvic parameters in adults with spinal deformity.

Multilevel Corpectomy With Anterior Column Reconstruction and Plating for Subaxial Cervical Osteomyelitis.

STUDY DESIGN: A retrospective case series. OBJECTIVE: The aim of this study was to evaluate patients with cervical spine osteomyelitis who underwent multilevel (≥2) subaxial corpectomies and anterior column reconstruction and plating. SUMMARY OF BACKGROUND DATA: Neglected multilevel subaxial cervical osteomyelitis is a potentially dangerous disease. As it is rare, early radiographic and clinical outcomes after multilevel anterior corpectomy and reconstruction for subaxial cervical osteomyelitis are incompletely defined. METHODS: Adults who underwent multilevel corpectomy and anterior plating/reconstruction for subaxial cervical osteomyelitis at two institutions were reviewed. Analysis of patient demographics, operative details, and radiographic cervical alignment parameters [segmental kyphosis, cervical lordosis, C2-7 sagittal vertical axis (SVA)] was performed. RESULTS: Nineteen patients [15 males, four females; average age 48 years (20-81 yrs)] met inclusion criteria. The majority had pre-operative neurologic deficits or was immunosuppressed. All were treated with ≥6 weeks of intravenous antibiotics following operation. All had anterior plating/reconstruction with titanium cages (expandable-6; mesh-6) or structural bone graft (fibular allogaft-6; tricortical iliac crest-1). The average number of corpectomies was 2.4 (2-4). The average numbers of levels fused anteriorly was 4.4 (4-6) and posteriorly was 6.3 (4-9). The majority of patients (74%) was treated with an anterior/posterior approach. Average follow-up was 16 ±â€Š9 months. There was significant improvement in all cervical alignment parameters (segmental kyphosis, C2-7 SVA, cervical lordosis). No intraoperative complications occurred and no patient deteriorated neurologically postoperatively. Postoperative complications included anterior cage/graft dislodgement (n = 2), recurrent neck hematomas requiring revision (n = 1), epidural hematoma (n = 1), and wound infection (n = 1). Sixty percent of patients had persistent neurologic dysfunction at final follow-up. None required reoperation for recurrent infection or pseudarthrosis. CONCLUSION: Although overall prognosis and neurologic recovery are guarded in medically fragile patients with multilevel subaxial cervical osteomyelitis, reconstruction with multilevel (≥2) corpectomy and anterior reconstruction/plating results in excellent restoration of cervical alignment and low rates of recurrent infection and pseudarthrosis. LEVEL OF EVIDENCE: 4.

Economic Impact of Revision Surgery for Proximal Junctional Failure After Adult Spinal Deformity Surgery: A Cost Analysis of 57 Operations in a 10-year Experience at a Major Deformity Center.

STUDY DESIGN: Retrospective cohort analysis. OBJECTIVE: To evaluate the economic impact of revision surgery for proximal junctional failures (PJF) after thoracolumbar fusions for adult spinal deformity (ASD). SUMMARY OF BACKGROUND DATA: PJF after fusions for ASD is a major cause of disability. Although clinical sequelae are described, PJF-revision operation costs are incompletely defined. METHODS: Consecutive adults who underwent thoracolumbar fusions for ASD (August, 2003 to January, 2013) were evaluated. Inclusion criteria include construct from pelvis to L2 or above and minimum 6 months follow-up after the index ASD operation. Direct costs (surgical supplies/implants, room/care, pharmacy, services) were identified from medical billing data and calculated for index ASD operations and subsequent surgeries for PJF. Not included in direct cost data were indirect costs, charges, surgeon fees, or revision operations for indications other than PJF (i.e., pseudarthrosis). Patients were compared based on the construct's upper-instrumented vertebra: upper thoracic (UT: T1-6) versus thoracolumbar junction (TLjxn: T9-L2). RESULTS: Of 501 patients, 382 met inclusion criteria. Fifty-one patients [UT:14; TLjxn: 40 at index; average follow-up 32.6 months (6-92 months)] had revisions for PJF, which summed to $3.2 million total direct cost. Average direct cost of index operations for the cohort ($68,294) was significantly greater than PJF-revisions ($55,547). Compared with TLjxn, UT had a significantly higher average cost for index operations ($79,860 vs. $65,868). However, PJF-revision cases were similar in average cost (UT:$60,103; TLjxn:$53,920; P = 0.09). Costs of PJF amounted to an additional 12.1% of the total index surgical cost in 382 patients. CONCLUSION: Revision operations for PJF after long thoracolumbar fusions for ASD are associated with an average direct cost of $55,547 per case. Revision costs for PJF are similar based on the index procedure's upper-instrumented vertebra level. At a major tertiary center over a 10-year period, PJF came at a very significant economic expense amounting to $3.2 million for 57 cases. LEVEL OF EVIDENCE: 3.

Anterior corpectomy via the mini-open, extreme lateral, transpsoas approach combined with short-segment posterior fixation for single-level traumatic lumbar burst fractures: analysis of health-related quality of life outcomes and patient satisfaction.

OBJECTIVE: The authors present clinical outcome data and satisfaction of patients who underwent minimally invasive vertebral body corpectomy and cage placement via a mini-open, extreme lateral, transpsoas approach and posterior short-segment instrumentation for lumbar burst fractures. METHODS: Patients with unstable lumbar burst fractures who underwent corpectomy and anterior column reconstruction via a mini-open, extreme lateral, transpsoas approach with short-segment posterior fixation were reviewed retrospectively. Demographic information, operative parameters, perioperative radiographic measurements, and complications were analyzed. Patient-reported outcome instruments (Oswestry Disability Index [ODI], 12-Item Short Form Health Survey [SF-12]) and an anterior scar-specific patient satisfaction questionnaire were recorded at the latest follow-up. RESULTS: Twelve patients (7 men, 5 women, average age 42 years, range 22-68 years) met the inclusion criteria. Lumbar corpectomies with anterior column support were performed (L-1, n = 8; L-2, n = 2; L-3, n = 2) and supplemented with short-segment posterior instrumentation (4 open, 8 percutaneous). Four patients had preoperative neurological deficits, all of which improved after surgery. No new neurological complications were noted. The anterior incision on average was 6.4 cm (range 5-8 cm) in length, caused mild pain and disability, and was aesthetically acceptable to the large majority of patients. Three patients required chest tube placement for pleural violation, and 1 patient required reoperation for cage subsidence/hardware failure. Average clinical follow-up was 38 months (range 16-68 months), and average radiographic follow-up was 37 months (range 6-68 months). Preoperative lumbar lordosis and focal lordosis were significantly improved/maintained after surgery. Patients were satisfied with their outcomes, had minimal/moderate disability (average ODI score 20, range 0-52), and had good physical (SF-12 physical component score 41.7% ± 10.4%) and mental health outcomes (SF-12 mental component score 50.2% ± 11.6%) after surgery. CONCLUSIONS: Anterior corpectomy and cage placement via a mini-open, extreme lateral, transpsoas approach supplemented by short-segment posterior instrumentation is a safe, effective alternative to conventional approaches in the treatment of single-level unstable burst fractures and is associated with excellent functional outcomes and patient satisfaction.

Comparison of Expandable and Fixed Interbody Cages in a Human Cadaver Corpectomy Model: Fatigue Characteristics.

STUDY DESIGN: In vitro cadaver biomechanics study. OBJECTIVE: The goal of this study is to compare the in situ fatigue life of expandable versus fixed interbody cage designs. SUMMARY OF BACKGROUND DATA: Expandable cages are becoming more popular, in large part, due to their versatility; however, subsidence and catastrophic failure remain a concern. This in vitro analysis investigates the fatigue life of expandable and fixed interbody cages in a single level human cadaver corpectomy model by evaluating modes of subsidence of expandable and fixed cages as well as change in stiffness of the constructs with cyclic loading. METHODS: Nineteen specimens from 10 human thoracolumbar spines (T10-L2, L3-L5) were biomechanically evaluated after a single level corpectomy that was reconstructed with an expandable or fixed cage and anterior dual rod instrumentation. All specimens underwent 98 K cycles to simulate 3 months of postoperative weight bearing. In addition, a third group with hyperlordotic cages was used to simulate catastrophic failure that is observed in clinical practice. RESULTS: Three fixed and 2 expandable cages withstood the cyclic loading despite perfect sagittal and coronal plane fitting of the endcaps. The majority of the constructs settled in after initial subsidence. The catastrophic failures that were observed in clinical practice could not be reproduced with hyperlordotic cages. However, all cages in this group subsided, and 60% resulted in endplate fractures during deployment of the cage. CONCLUSIONS: Despite greater surface contact area, expandable cages have a trend for higher subsidence rates when compared with fixed cages. When there is edge loading as in the hyperlordotic cage scenario, there is a higher risk of subsidence and intraoperative fracture during deployment of expandable cages.

Integrity of Damage Control Posterior Spinal Fusion Constructs for Patients With Polytrauma: A Biomechanical Investigation.

STUDY DESIGN: Biomechanical. OBJECTIVE: Evaluate spinal stability achieved with different levels of posterior percutaneous fixation (postPerc) for thoracolumbar fractures in cadavers subjected to ICU activities. SUMMARY OF BACKGROUND DATA: "Spine damage control" involves postPerc performed within 24 hours of injury and staged, elective, definitive stabilization. Amount of instrumentation needed to initially achieve adequate spinal stability, minimize morbidity, and accommodate ICU care needs between stages are not defined. METHODS: In full-unembalmed cadavers motion-tracking sensors were placed at T11 and L1. A T12 corpectomy with PLC injury was stabilized with 1, 2, and 3 levels of PostPerc above/below the injury. Motions between T11 and L1 were measured during Log-Roll and Sit-Up on an ICU bed. After in situ testing, anatomic spinal motion ranges were determined under pure moment loads. RESULTS: 5 cadavers were evaluated. For Log-Roll, 2 and 3 levels above/below restored stability to intact, whereas 1 level above/below did not for axial rotation. For translation, all instrumentation restored stability to intact. During Sit-Up, a linear increase in flexion was observed. At 45° Sit-Up, 2 and 3 levels above/below were similar to intact for flexion; 1 level above/below had significantly more flexion. All instrumentations restored translation to intact for Sit-Up; significantly more axial collapse occurred for instrumentation compared with intact. During ex situ testing, 2 and 3 levels above/below were similar; 1 level above/below had significantly greater laxity in flexion, extension, and axial rotation. CONCLUSION: Posterior instrumentation 2 or 3 levels above/below a severe thoracolumbar fracture model can restore spinal stability back to its intact condition. 2 levels of fixation above/below this "worst-case scenario" is minimum fixation sufficient to provide absolute spinal stability in the ICU setting as a "Damage Control" technique in patients with polytrauma. In less severe injury models, 1 level of fixation above/below may provide adequate spinal stability; although this should be confirmed in future investigations. LEVEL OF EVIDENCE: N/A.

Ossification of the posterior longitudinal ligament of the cervical spine in 3161 patients: a CT-based study.

STUDY DESIGN: A cross-sectional study. OBJECTIVE: To examine the prevalence of ossification of the posterior longitudinal ligament (OPLL) and ossification of the nuchal ligament (ONL) of the cervical spine in the San Francisco area. SUMMARY OF BACKGROUND DATA: The prevalence of OPLL and ONL is unknown in the non-Asian population. METHODS: This computed tomography-based cross-sectional study assessed the prevalence of OPLL and ONL within the cervical spine of patients treated at a level 1 trauma center between 2009 and 2012. The prevalence of both OPLL and ONL was compared between racial groups. RESULTS: Of the 3161 patients (mean age, 51.2 ± 21.6 yr; 66.1% male), there were 1593 Caucasians (50.4%), 624 Asians (19.7%), 472 Hispanics (14.9%), 326 African Americans (10.3%), 62 Native Americans (2.0%), and 84 Others (2.7%). The prevalence of cervical OPLL was 2.2% (95% confidence interval [CI]: 1.7-2.8). The adjusted prevalence was 1.3% in Caucasian Americans (95% CI: 0.7-2.3), 4.8% in Asian Americans (95% CI: 2.8-8.1), 1.9% in Hispanic Americans (95% CI: 0.9-4.0), 2.1% in African Americans (95% CI: 0.9-4.8), and 3.2% in Native Americans (95% CI: 0.8-12.3). The prevalence of OPLL in Asian Americans was significantly higher than that in Caucasian Americans (P = 0.005). ONL was detected in 346 patients and the prevalence was 10.9% (95% CI: 10.0-12.0). The adjusted prevalence of ONL was 7.3% in Caucasian Americans (95% CI: 5.8-9.3), 26.4% in Asian Americans (95% CI: 21.9-31.5), 7.4% in Hispanic Americans (95% CI: 5.2-10.5), 2.5% in African Americans (95% CI: 1.2-4.9), and 25.8% in Native Americans (95% CI: 16.5-37.5). ONL was significantly more common in Asian Americans than in Caucasian Americans, Hispanic Americans, and African Americans (P = 0.001). CONCLUSION: This study also demonstrated that OPLL and ONL were significantly more common in Asian Americans than in Caucasian Americans. LEVEL OF EVIDENCE: 3.

Cervical spine clearance protocols in Level I, II, and III trauma centers in California.

BACKGROUND CONTEXT: Cervical spine clearance protocols were developed to standardize the clearance of the cervical spine after blunt trauma and prevent secondary neurologic injuries. The degree of incorporation of evidence-based guidelines into protocols at trauma centers in California is unknown. PURPOSE: To evaluate the cervical spine clearance protocols in all trauma centers of California. STUDY DESIGN: An observational cross-sectional study. PATIENT SAMPLE: Included from Level I, II, III trauma centers in California. OUTCOME MEASURES: The self-reported outcomes of each trauma center's cervical spine clearance protocols were assessed. METHODS: Level I (n=15), II (n=30), and III (n=11) trauma centers in California were contacted. Each available protocol was reviewed for four scenarios: clearing the asymptomatic patient, the initial imaging modality used in patients not amenable to clinical clearance, and the management strategies for patients with persistent neck pain with a negative computed tomography (CT) scan and those who are obtunded. Results were compared with the 2009 Eastern Association for the Surgery of Trauma (EAST) cervical spine clearance guidelines. RESULTS: The response rate was 96%. Sixty-three percent of California's trauma centers (Level I, 93%; Level II, 60%; Level III, 27%) had written cervical spine clearance protocols. For asymptomatic patients, 83% of Level I and 61% of Level II centers used National Emergency X-Radiography Utilization Study criteria with/without painless range of motion. For those requiring imaging, 67% of Level I and 56% of Level II centers stated a CT scan should be the first line of imaging. For obtunded patients and patients with persistent neck pain and a negative CT scan, more than 90% of Level I and more than 70% of Level II trauma centers incorporated the 2009 EAST recommendations. No institution recommended passive flexion-extension radiographs for the obtunded patient. CONCLUSIONS: Written cervical spine clearance protocols exist in 63% of California's trauma centers and only 51% of the centers have protocols that follow current evidence-based guidelines. Standardization and utilization of these protocols should be encouraged to prevent missed injuries and secondary neurologic injuries.

Revision surgery for lumbar pseudarthrosis.

BACKGROUND CONTEXT: Revision surgery for pseudarthrosis after a lumbar spinal fusion has unpredictable functional results. PURPOSE: The aim of this study was to determine the clinical outcomes of revision surgery to fuse the pseudarthrosis site based on the two most common diagnoses (degenerative disc disease [DDD] vs. spondylolisthesis). STUDY DESIGN: Patients who had a revision surgery between 1995 and 2004 for lumbar pseudarthrosis after short segment lumbar spinal fusion were identified through the institution's Spine Center surgery database. A retrospective chart review of clinical, hospital, and anesthesia records was then performed. PATIENT SAMPLE: Sixty-six patients were included in the study (28 patients with DDD and 38 patients with spondylolisthesis). Inclusion criteria were a surgical diagnosis of pseudarthrosis with a prior fusion of one or two motion segments, minimum 24 months of follow-up, and a diagnosis of either symptomatic DDD or spondylolisthesis as the primary indication for the index fusion surgery. OUTCOME MEASURES: The Oswestry disability index (ODI) and a self-assessment questionnaire were used to evaluate clinical outcomes. METHODS: A retrospective chart and radiographic review was performed. Statistical analysis was done using Student t test for ODI scores and chi-square test for discrete variables from the outcome questionnaires. RESULTS: Follow-up radiographs were available for 64 patients (97%), and a fusion rate of 100% was found in both groups for the radiographs examined. The mean postoperative ODI score was 53.3 (30-84.4) for DDD patients and 37.2 (2.5-76) for the spondylolisthesis group (p<.01). Only 50% of the patients in the DDD group felt that their overall well-being had improved since the surgery. In the spondylolisthesis group, 64% of patients stated that their overall well-being had improved since their revision surgery. CONCLUSIONS: The clinical outcomes after revision surgery for pseudarthrosis are worse in patients with DDD compared with spondylolisthesis despite successful repair of nonunion. Risks and benefits should be well discussed with the patients before deciding on surgical treatment for the management of pseudarthrosis, especially in patients with previous short-segment fusions done for DDD.

Local intrawound vancomycin powder decreases the risk of surgical site infections in complex adult deformity reconstruction: a cost analysis.

STUDY DESIGN: Retrospective cohort analysis. OBJECTIVE: To evaluate the rate of surgical site infections (SSIs) and cost-effectiveness of the use of intraoperative vancomycin powder in thoracolumbar adult deformity procedures. SUMMARY OF BACKGROUND DATA: The rates of SSI remain unacceptably high in adult spinal deformity surgery despite routine intravenous antibiotics. Vancomycin powder applied directly to the wound intraoperatively has shown promise for decreasing SSI in spine surgery. METHODS: Adults who underwent adult deformity reconstruction by 2 surgeons between 2008 and 2012 with a minimum of 3 months of clinical follow-up were retrospectively reviewed. The patients were subdivided into those who had received only routine perioperative intravenous antibiotics (control) and those who received intravenous antibiotics and 2 g of vancomycin powder applied into the surgical wound. The primary outcome was SSI within 90 days. Secondary outcomes included surgical/clinical parameters and SSI-related medical costs based on hospital billing records. RESULTS: Two hundred fifteen patients were evaluated-controls (n=64) and vancomycin powder group (n=151). The average number of levels fused was 10 (5-17, control) and 12 (5-19, vancomycin). The mean follow-up was 34 months (3-68 mo, control) and 18 months (3-35 mo, vancomycin) (P<0.05). There were significantly fewer hospital readmissions within 90 days for SSI in patients who received vancomycin powder (2.6%; 4/151) compared with controls (10.9%; 7/64) (P=0.01). There were no reported adverse events related to the intrawound vancomycin use. The average cost per patient of treating a postoperative SSI was higher in the control group ($34,388) than in the study group ($28,169). With the use of vancomycin powder, there was a cost saving of $244,402 per 100 complex spinal procedures. CONCLUSION: Local application of vancomycin powder significantly decreased SSI for adults undergoing spinal reconstructive surgery. This resulted in cost savings of $244,402 per 100 thoracolumbar adult deformity procedures. LEVEL OF EVIDENCE: 3.

Reexamination of pelvic inlet and outlet images using 3-dimensional computed tomography reconstructions.

OBJECTIVES: Inlet and outlet views are essential in the evaluation of patients with pelvic injuries. The optimal angles that should be used to obtain these views are still debated. METHODS: Computed tomography scans of 70 patients without pelvic ring injuries were analyzed. Using the raw data from the computed tomography images, virtual pelvic x-rays were generated. The images were rotated 1 degree at a time and a total of 360 images were generated. The same procedure was repeated to create solid 3-dimensional (3D) reconstructions. Two trauma-trained orthopaedic surgeons then reviewed all 360 images to select inlet and outlet views as described in previous literature. Intraclass correlation coefficients were calculated for each inlet and outlet value. RESULTS: The average inlet angle (caudal tilt) that was required to achieve a view where the promontory overlaps the S1 body was found to be 26.7 degrees (95% confidence interval, 25-29) with virtual x-rays and 24.3 degrees (95% confidence interval, 22-26) with 3D reconstructions. The average outlet angle (cephalad tilt) that was required to achieve a view where the superior border of the pubic symphysis overlaps the S2 body was 43.7 degrees (95% confidence interval, 42-45) with virtual x-rays and 43.8 degrees (95% confidence interval, 42-45) with 3D reconstructions. There was no difference in these angles based on gender, whereas sacral dysmorphism increased the angle needed to obtain the outlet view by an average of 5 degrees. CONCLUSIONS: This study demonstrated that the ideal angle to obtain inlet views should be approximately 25 degrees and to obtain outlet views should be approximately 45 degrees during screening x-rays to evaluate patients who were diagnosed with pelvic injuries. Application of these new values in the clinical practice would provide higher rates of adequate studies and further prospective clinical studies should be performed to validate these parameters.

Cervical spine clearance protocols in level 1 trauma centers in the United States.

STUDY DESIGN: Observational, cross-sectional. OBJECTIVE: To evaluate cervical spine clearance protocols in level 1 trauma centers in the United States. SUMMARY OF BACKGROUND DATA: Cervical spine clearance protocols were developed to prevent missed injuries that could result in neurological deficits. The degree of incorporation of evidence-based guidelines into protocols at trauma centers in the United States is unknown. METHODS: Level 1 trauma (n = 191) centers in the United States were contacted. Each available protocol was reviewed for 4 scenarios: clearing the asymptomatic patient, the imaging used in patients not amenable to clinical clearance, the management strategies for patients with persistent neck pain with a negative computed tomographic (CT) scan, and those who are obtunded. RESULTS: The response rate was 87%. Cervical spine clearance protocols existed in 57% of the institutions. National Emergency X-Radiography Utilization Study criteria to clear asymptomatic patients were recommended in 89% of protocols. Sixty percent of protocols used CT scans as the first line of imaging. In patients with persistent neck pain with negative CT scan flexion-extension plain radiographs were the most common (30%) next step for clearance. In patients who are obtunded, a CT scan followed by a magnetic resonance imaging was the most common method (31%) of clearance. Eight percent of the protocols recommended dynamic flexion-extension views in patients who are obtunded, which are contraindicated. CONCLUSION: Written cervical spine clearance protocols exist in 57% of level 1 trauma centers in the United States. These protocols are highly variable and standardization and utilization of these protocols should be encouraged in all trauma centers to prevent missed injuries and neurological catastrophes. LEVEL OF EVIDENCE: 4.