Proposal for a classification system of radiographic bone changes after cervical disc replacement.

Background: The goal of this study is to propose a classification system with a common nomenclature for radiographic observations of periprosthetic bone changes following cTDR.

Methods: Aided by serial plain radiographs from recent cTDR cases (34 patients; 44 devices), a panel of experts assembled for the purpose of creating a classification system to aid in reproducibly and accurately identifying bony changes and assessing cTDR radiographic appearance. Subdividing the superior and inferior vertebral bodies into 3 equal sections, observed bone loss such as endplate rounding, cystic erosion adjacent to the endplate, and cystic erosion not adjacent to the endplate, is recorded.

Utilization of CT scanning associated with complex spine surgery.

Background: Due to the risk associated with exposure to ionizing radiation, there is an urgent need to identify areas of CT scanning overutilization. While increased use of diagnostic spinal imaging has been documented, no previous research has estimated the magnitude of follow-up imaging used to evaluate the postoperative spine.

Methods: This retrospective cohort study quantifies the association between spinal surgery and CT utilization.

The Kinematics and Spondylosis of the Lumbar Spine Vary Depending on the Levels of Motion Segments in Individuals With Low Back Pain.

Study Design: A prospective cohort study.

Objective: The aim of this study was to identify associations of spondylotic and kinematic changes with low back pain (LBP).

Summary Of Background Data: The ability to characterize and differentiate the biomechanics of both the symptomatic and asymptomatic lumbar spine is crucial to alleviate the sparse literature on the association of lumbar spine biomechanics and LBP.

A cost comparison of unicompartmental and total knee arthroplasty.

Background: Unicompartmental knee arthroplasty (UKA) is an alternative to total knee arthroplasty (TKA) in appropriately selected patients. There is a paucity of data comparing hospital resource utilization and costs for UKA versus TKA.

Methods: We retrospectively reviewed 128 patients who underwent UKA or TKA for osteoarthritis by a single surgeon in the 2011 Fiscal Year.

Lumbar disc degeneration is an equally important risk factor as lumbar fusion for causing adjacent segment disc disease.

Treatment of degenerative spinal disorders by fusion produces abnormal mechanical conditions at mobile segments above or below the site of spinal disorders and is clinically referred to as adjacent segments disc disease (ASDD) or transition syndrome in the case of a previous surgical treatment. The aim of the current study is to understand with the help of poro-elastic finite element models how single or two level degeneration of lower lumbar levels influences motions at adjacent levels and compare the findings to motions produced by single or two level fusions when the adjacent disk has varying degree of degeneration. Validated grade-specific finite element models including varying grades of disc degeneration at lower lumbar levels with and without fusion were developed and used to determine motions at all levels of the lumbar spine due to applied moment loads.

Ligamentum flavum hypertrophy in asymptomatic and chronic low back pain subjects.

Purpose: To examine ligamentum flavum thickness using magnetic resonance (MR) images to evaluate its association with low back pain symptoms, age, gender, lumbar level, and disc characteristics.

Materials And Methods: Sixty-three individuals were part of this IRB-approved study: twenty-seven with chronic low back pain, and thirty-six as asymptomatic. All patients underwent MR imaging and computed tomography (CT) of the lumbar spine.

Stem cell therapy for intervertebral disc regeneration: obstacles and solutions.

Intervertebral disc (IVD) degeneration is frequently associated with low back and neck pain, which accounts for disability worldwide. Despite the known outcomes of the IVD degeneration cascade, the treatment of IVD degeneration is limited in that available conservative and surgical treatments do not reverse the pathology or restore the IVD tissue. Regenerative medicine for IVD degeneration, by injection of IVD cells, chondrocytes or stem cells, has been extensively studied in the past decade in various animal models of induced IVD degeneration, and has progressed to clinical trials in the treatment of various spinal conditions.

Spontaneous resorption of a large cervical herniated nucleus pulposus.

The majority of patients with symptomatic herniated discs can be successfully and conservatively managed and can achieve clinical improvement without surgical intervention. Resorption of the herniated nucleus pulposus (HNP) is 1 conservative mechanism for clinical improvement. We present the case of a 76-year-old healthy man with acute cervical radicular right arm pain and positive Spurling test.

In vivo 3-dimensional morphometric analysis of the lumbar foramen in healthy subjects.

Study Design: In vivo 3-dimensional (3D) morphometric analysis of the lumbar foramen by using 3D computed tomographic models in normal subjects.

Objective: To describe foraminal geometry in an asymptomatic cohort measured in 3D.

Summary Of Background Data: Appropriate assessment of the complex 3D lumbar foraminal geometry is key to correct radiculopathy diagnosis and treatment planning.

A perioperative cost analysis comparing single-level minimally invasive and open transforaminal lumbar interbody fusion.

Background Context: Emerging literature suggests superior clinical short- and long-term outcomes of MIS (minimally invasive surgery) TLIFs (transforaminal lumbar interbody fusion) versus open fusions. Few studies to date have analyzed the cost differences between the two techniques and their relationship to acute clinical outcomes.

Purpose: The purpose of the study was to determine the differences in hospitalization costs and payments for patients treated with primary single-level MIS versus open TLIF.

Damage accumulation location under cyclic loading in the lumbar disc shifts from inner annulus lamellae to peripheral annulus with increasing disc degeneration.

It is difficult to study the breakdown of lumbar disc tissue over several years of exposure to bending and lifting by experimental methods. In our earlier published study we have shown how a finite element model of a healthy lumbar motion segment was used to predict the damage accumulation location and number of cyclic to failure under different loading conditions. The aim of the current study was to extend the continuum damage mechanics formulation to the degenerated discs and investigate the initiation and progression of mechanical damage.

Relationship between biomechanical changes at adjacent segments and number of fused bone grafts in multilevel cervical fusions: a finite element investigation.

Object: Biomechanical studies have shown that anterior cervical fusion construct stiffness and arthrodesis rates vary with different reconstruction techniques; however, the behavior of the adjacent segments in the setting of different procedures is poorly understood. This study was designed to investigate the adjacent-segment biomechanics after 3 different anterior cervical decompression and fusion techniques, including 3-level discectomy and fusion, 2-level corpectomy and fusion, and a corpectomy-discectomy hybrid technique. The authors hypothesized that biomechanical changes at the segments immediately superior and inferior to the multilevel fusion would be inversely proportional to the number of fused bone grafts and that these changes would be related to the type of fusion technique.

Biomechanics of adjacent segments after a multilevel cervical corpectomy using anterior, posterior, and combined anterior-posterior instrumentation techniques: a finite element model study.

Background Context: Adjacent segment degeneration (ASD) after cervical fusion is a clinical concern. Despite previous studies documenting the biomechanical effects of multilevel cervical fusion on segments immediately superior and inferior to the operative segments, the pathogenesis of the initiation of degeneration progression in neighboring segments is still poorly understood.

Purpose: To test the hypothesis that changes in range of motion, disc stresses, and facet loads would be highest at the superior adjacent segment (C3-C4) after anterior C4-C7 corpectomy and fusion and that these changes would be the least in anterior fixation and the greatest in posterior or combined anterior-posterior instrumentation techniques.

Initiation and progression of mechanical damage in the intervertebral disc under cyclic loading using continuum damage mechanics methodology: A finite element study.

It is difficult to study the breakdown of disc tissue over several years of exposure to bending and lifting by experimental methods. There is also no finite element model that elucidates the failure mechanism due to repetitive loading of the lumbar motion segment. The aim of this study was to refine an already validated poro-elastic finite element model of lumbar motion segment to investigate the initiation and progression of mechanical damage in the disc under simple and complex cyclic loading conditions.

Posterior facet load changes in adjacent segments due to moderate and severe degeneration in C5-C6 disc: a poroelastic C3-T1 finite element model study.

Study Design: Biomechanics of normal vertebral segments adjacent to a degenerated segment in the cervical spine.

Objective: To test the hypothesis that posterior facet joints of adjacent segments are loaded more when degeneration occurs in the intermediate disc segment.

Summary Of Background Data: Degeneration progression in adjacent segments is a clinical concern.

Corpectomy versus discectomy for the treatment of multilevel cervical spine pathology: a finite element model analysis.

Background Context: After multilevel fusions, construct failure because of pseudoarthrosis and instrumentation complications is a well-recognized clinical problem. Little is known about the biomechanics governing the cervical spine after different anterior reconstruction techniques, specifically the number of bone grafts and screws used and whether discectomies versus corpectomies have been performed. A few research groups have compared the efficacy of corpectomy and discectomy procedures under common testing conditions; however, no quantitative stress measurements at graft-end plate and bone-screw interfaces have been reported to date.

Comparing effects of kyphoplasty, vertebroplasty, and non-surgical management in a systematic review of randomized and non-randomized controlled studies.

Purpose: To determine if differences in safety or efficacy exist between balloon kyphoplasty (BKP), vertebroplasty (VP) and non-surgical management (NSM) for the treatment of osteoporotic vertebral compression fractures (VCFs).

Methods: As of February 1, 2011, a PubMed search (key words: kyphoplasty, vertebroplasty) resulted in 1,587 articles out of which 27 met basic selection criteria (prospective multiple-arm studies with cohorts of ≥ 20 patients). This systematic review adheres to preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines.

In vivo topographic analysis of lumbar facet joint space width distribution in healthy and symptomatic subjects.

Study Design: In vivo 3-dimensional facet joint space width measurement.

Objective: To determine lumbar facet joint space width within clinically relevant topographical zones in vivo and its correlations with age, level, and presence of lower back pain symptoms.

Summary Of Background Data: Facet joint gap narrowing, articular cartilage thinning, and subarticular cortical bone hypertrophy are frequently observed age-related changes.

FMCSA's medical review board: five years of progress in commercial driver medical examinations.

Objective: To revise and update guidance recommendations to the Federal Motor Carrier Safety Administration for evaluating commercial drivers.

Methods: The Federal Motor Carrier Safety Administration's medical review board has addressed guidance for commercial drivers for the past 5 years. The processes for most topics involve comprehensive literature searches, evidence reports, medical expert panel reports, critique of the literature, testimony, and decision making.

Management of degenerative disk disease and chronic low back pain.

Degenerative disk disease is a strong etiologic risk factor of chronic low back pain (LBP). A multidisciplinary approach to treatment is often warranted. Patient education, medication, and cognitive behavioral therapies are essential in the treatment of chronic LBP sufferers.