Survival of atlanto-occipital dissociation correlates with atlanto-occipital distraction, injury severity score, and neurologic status.

BACKGROUND: Case series suggest that atlanto-occipital dissociation (AOD) is a potentially survivable injury. Intuitively, a significant neurologic injury, a high degree of initial distraction, and more severe associated injuries would decrease the likelihood of survival. However, this has never been demonstrated for this injury pattern in a statistically meaningful way. The purpose of this study was to assess the relationship of atlanto-occipital distraction, presence of a complete neurologic injury, and Injury Severity Score (ISS) to the rate of survival in AOD. METHODS: One thousand one hundred seventy-four patients from 2005 to 2009 comprehensive trauma database were retrospectively reviewed. Fourteen patients diagnosed with AOD were included in the study. Outcome measures assessed included survival, neurologic status, and ISS. The basion-dens interval (BDI) was measured on the computed tomography scan. Fisher's exact test and Wilcoxon's test were used to evaluate possible associations. RESULTS: Six patients died with complete, high cervical, spinal cord injuries. Follow-up for survivors ranged from 6 months to 2 years. Mortality was associated with the presence of complete neurologic deficit (p = 0.0047), a high basion-dens interval (>16 mm, p = 0.015), and a high ISS (p = 0.0373). CONCLUSIONS: AOD is a potentially survivable injury; however, there may be identifiable subsets of patients where the injury is so severe that treatment is unlikely to change the outcome. This is the first study to show that the ISS and the presence of a complete neurologic injury correlate with nonsurvivability of this devastating injury. A larger case series would help to generalize the results, given the small sample size.

Dual-energy estimates of volumetric bone mineral densities in the lumbar spine using quantitative computed tomography better correlate with fracture properties when compared to single-energy BMD outcomes.

It is estimated that over 200 million people worldwide are affected by osteoporosis. Vertebral fracture risk prediction using dual energy x-ray absorptiometry (DXA) is confounded by limitations of the technology, such as 2D measurements of bone mineral density (BMD), inability to measure bone distribution and heterogeneity, and potential overestimations of BMD due to degenerative diseases. To overcome these shortcomings, single energy (SE) quantitative computed tomography (QCT) imaging estimates of Hounsfield units (HU) and volumetric BMD have been implemented as alternative methodologies for assessing fracture risk. However, marrow fat within the vertebrae can highly affect the vBMD and fracture properties estimations. To address this issue, 54 vertebrae were dissected from nine cadaveric spines and scanned using SE-QCT (120kVp) and dual energy (DE)-QCT (80/140 kVp), with the latter accounting for marrow fat within the vertebrae. The vertebrae were then scanned using DXA and subjected to mechanical testing to obtain fracture properties. aBMD outcomes from DXA showed a better correlation with DE-QCT vBMD versus SE outcomes [DE: aBMD vs. vBMD (R2: 0.61); SE: aBMD vs. vBMD (R2: 0.27)]. SE-QCT underestimated vertebral vBMD by -56% (p<0.0001) when compared to DE-QCT. vBMD estimates from SE-QCT could predict 45% and 37% of the vertebral failure loads and stiffness, respectively, compared to 67% and 46% from DE-QCT. DE-QCT vBMD outcomes highly correlated with fracture properties of vertebrae as compared to SE-QCT metrics. As DE scanning has the ability to correct for the effects of bone marrow fat, estimated vBMD from SE-QCT were significantly underestimated compared to DE-QCT. Dual energy CT scanning has the potential to more accurately predict vertebral failure and aid the clinician in the evaluation of appropriate interventions. Future studies should consider implementing DE-QCT in their fracture assessment.

Obesity and calcification of the ligaments of the spine: a comprehensive CT analysis of the entire spine in a random trauma population.

BACKGROUND CONTEXT: Obesity, which is currently surging to epidemic levels within the United States, has been linked to hyperostotic conditions like diffuse idiopathic skeletal hyperostosis (DISH) and ossification of the posterior longitudinal ligament (OPLL). Excess adipose tissue and insulin-resistance may cause a systemic increase in serum levels of proinflammatory cytokines and these signals can affect bone metabolism. Spinal ligaments and discs may have receptors for these signaling molecules. Anecdotal observations at this institution suggested that there is a clinically important subset of younger patients with obesity and multilevel stenosis in the presence of unusual calcification of the spinal ligaments that is distinct from DISH. PURPOSE: To determine if there is an association between truncal obesity and calcifications of the spine in nonelderly adults. STUDY DESIGN/SETTING: This is a retrospective analysis of 214 sequential trauma patients between the ages of 29 and 50. Patients' age, sex, truncal obesity, history of hypertension, and diabetes were assessed for association with ligamentous calcification of the spine. PATIENT SAMPLE: Sequential trauma patients were chosen from our institution's trauma database between 2006 and 2007. METHODS: Full spine computed tomography (CT) imaging was examined for bone formation in the region of the anterior longitudinal ligament (ALL) and annulus, posterior longitudinal ligament (PLL) and annulus, and the ligamentum flavum (LF). Visceral and subcutaneous abdominal fat were also evaluated. The authors report no study funding sources or conflicts of interest. OUTCOME MEASURES: Calcification of the ALL, PLL, and LF were assigned a score at each level and then combined for a total calcification score (TCS) for the entire spine. Obesity was estimated using a truncal body mass index (TBMI) by using a previously validated CT derived truncal total adiposity volume (TAV). RESULTS: ALL calcification was associated with age, male gender, hypertension, and increased adiposity. PLL calcification was significantly associated with age and hypertension. LF calcification was only associated with increased obesity. CONCLUSIONS: In our analysis of nonelderly patients, LF calcification was independently associated with truncal obesity. This implies obesity plays a greater role in calcification than could be accounted for by simply age-related degeneration or gender.

How stem cell composition in bone marrow aspirate relates to clinical outcomes when used for cervical spine fusion.

Anterior cervical discectomy and fusion (ACDF) is performed to relieve pain caused by degenerative disk disease and nerve obstruction. As an alternative to bone graft, autologous concentrated bone marrow aspirate (CBMA) is used to achieve vertebral fusion with a satisfactory success rate. This has been attributed in part to bone marrow-resident mesenchymal stromal cells (MSCs) with the capacity to differentiate into osteoblasts and generate bone tissue. To date, there has been no study comparing cellular yields, MSC frequencies and their osteogenic potential with ACDF outcome. Patients (n = 24) received ACDF with CBMA and allograft bone matrix. Colony forming unit fibroblast (CFU-F) and CFU-osteoblasts (CFU-O) assays were performed on CBMA samples to enumerate MSCs (CFU-F) and osteogenic MSCs (CFU-O). CFUs were normalized to CBMA volume to define yield and also to mononuclear cells (MNC) to define frequency. After 1-year, fusion rates were good (86.7%) with pain and disability improved. There was a negative relationship between MNC and CFU-F measurements with age of patient and CFU-Os negatively correlated with age in females but not males. Tobacco use did not affect CBMA but was associated with poorer clinical outcome. Surprisingly, we found that while high-grade fusion was not associated with CFU-O, it correlated strongly (p<0.0067) with CBMA containing the lowest frequencies of CFU-F (3.0x10(-6)-5.83x10(-5) CFU-F/MNC). MNC levels alone were not responsible for the results. These observations suggest that osteogenesis by human bone marrow is controlled by homeostatic ratio of MSCs to other cellular bone marrow components rather than absolute level of osteogenic MSCs, and that a lower ratio of MSCs to other cellular components in marrow tends to predict effective osteogenesis during ACDF. The results presented herein challenge the current dogma surrounding the proposed mechanism of MSCs in bone healing.

Rapid Osteogenic Enhancement of Stem Cells in Human Bone Marrow Using a Glycogen-Synthease-Kinase-3-Beta Inhibitor Improves Osteogenic Efficacy In Vitro and In Vivo.

Non-union defects of bone are a major problem in orthopedics, especially for patients with a low healing capacity. Fixation devices and osteoconductive materials are used to provide a stable environment for osteogenesis and an osteogenic component such as autologous human bone marrow (hBM) is then used, but robust bone formation is contingent on the healing capacity of the patients. A safe and rapid procedure for improvement of the osteoanabolic properties of hBM is, therefore, sought after in the field of orthopedics, especially if it can be performed within the temporal limitations of the surgical procedure, with minimal manipulation, and at point-of-care. One way to achieve this goal is to stimulate canonical Wingless (cWnt) signaling in bone marrow-resident human mesenchymal stem cells (hMSCs), the presumptive precursors of osteoblasts in bone marrow. Herein, we report that the effects of cWnt stimulation can be achieved by transient (1-2 hours) exposure of osteoprogenitors to the GSK3ß-inhibitor (2'Z,3'E)-6-bromoindirubin-3'-oxime (BIO) at a concentration of 800 nM. Very-rapid-exposure-to-BIO (VRE-BIO) on either hMSCs or whole hBM resulted in the long-term establishment of an osteogenic phenotype associated with accelerated alkaline phosphatase activity and enhanced transcription of the master regulator of osteogenesis, Runx2. When VRE-BIO treated hBM was tested in a rat spinal fusion model, VRE-BIO caused the formation of a denser, stiffer, fusion mass as compared with vehicle treated hBM. Collectively, these data indicate that the VRE-BIO procedure may represent a rapid, safe, and point-of-care strategy for the osteogenic enhancement of autologous hBM for use in clinical orthopedic procedures. Stem Cells Translational Medicine 2018;7:342-353.

Influence of a platelet concentrate on prosthetic bone ingrowth in a rabbit model.

Recent studies have shown that an increase in bone ingrowth by addition of osteogenic growth factors can reduce micro motion and gross implant motion and contribute to joint implant stability through osseointegration. Platelet-rich plasma (PRP) has the potential to provide growth factors that may be conducive to osteointegration at the bone-implant interface. This study analyzed the influence of PRP on bone ingrowth upon a beaded metal implant in distal femurs of 22 rabbits. Rabbit limbs were randomly assigned to receive an implant plus PRP or plain implant. Half of the specimens were randomly assigned to a 2-week group (n = 20) or a 5-week group (n = 20). Histologic and histomorphometric comparison between implant alone and implant plus PRP, at 2 and 5 weeks, was performed. In both the 2- and 5-week comparisons, there was no statistical difference (p > .05) in bone ingrowth between the control and PRP group, despite a slight increase in trabecular bone growth in PRP groups. This study suggests that PRP is not a major contributing factor to bone ingrowth at the bone-implant interface. This supports growing evidence in the literature that PRP can lead to variable bone growth stimulation in vivo.

Rate of contralateral hip fracture after dynamic hip screw vs intramedullary nail for treatment of pertrochanteric hip fractures.

A retrospective, comparative study was performed reviewing the electronic medical records and digital radiographs of patients who underwent treatment for intertrochanteric and pertrochanteric hip fractures with either a hip screw and side plate (HSSP) or intramedullary nail. A total of 430 patients were treated with HSSP, and 725 were managed with a cephalomedullary nail (CMN). Of these, 103 sustained a contralateral hip fracture. Fixation technique was not associated with a significant difference in the rate of contralateral fracture. Among the patients with a contralateral fracture, the median time to contralateral fracture was 119.28 months following HSSP and 81.97 months following CMN. Bisphosphonate use was found to be a significant predictor of contralateral fracture for all patients, but when matching using propensity scores, its use was found to be insignificant. In conclusion, there was no difference in the rate of subsequent contralateral hip fracture when comparing HSSP with CMN. Additionally, the time to second surgery between the two treatment modalities was found to be statistically insignificant. It is unclear if bisphosphonate use increased the odds of having a contralateral fracture, regardless of the surgical intervention. The difference in the bisphosphonate effect using propensity score matching suggests that the results may be due to confounding variables and bias.

An allograft generated from adult stem cells and their secreted products efficiently fuses vertebrae in immunocompromised athymic rats and inhibits local immune responses.

BACKGROUND CONTEXT: Spine pain and the disability associated with it are epidemic in the United States. According to the National Center for Health Statistics, more than 650,000 spinal fusion surgeries are performed annually in the United States, and yet there is a failure rate of 15%-40% when standard methods employing current commercial bone substitutes are used. Autologous bone graft is the gold standard in terms of fusion success, but the morbidity associated with the procedure and the limitations in the availability of sufficient material have limited its use in the majority of cases. A freely available and immunologically compatible bone mimetic with the properties of live tissue is likely to substantially improve the outcome of spine fusion procedures without the disadvantages of autologous bone graft. PURPOSE: This study aimed to compare a live human bone tissue analog with autologous bone grafting in an immunocompromised rat model of posterolateral fusion. DESIGN/SETTING: This is an in vitro and in vivo preclinical study of a novel human stem cell-derived construct for efficacy in posterolateral lumbar spine fusion. METHODS: Osteogenically enhanced human mesenchymal stem cells (OEhMSCs) were generated by exposure to conditions that activate the early stages of osteogenesis. Immunologic characteristics of OEhMSCs were evaluated in vitro. The secreted extracellular matrix from OEhMSCs was deposited on a clinical-grade gelatin sponge, resulting in bioconditioned gelatin sponge (BGS). Bioconditioned gelatin sponge was used alone, with live OEhMSCs (BGS+OEhMSCs), or with whole human bone marrow (BGS+hBM). Efficacy for spine fusion was determined by an institutionally approved animal model using 53 nude rats. RESULTS: Bioconditioned gelatin sponge with live OEhMSCs did not cause cytotoxicity when incubated with immunologically mismatched lymphocytes, and OEhMSCs inhibited lymphocyte expansion in mixed lymphocyte assays. Bioconditioned gelatin sponge with live OEhMSC and BGS+hBM constructs induced profound bone growth at fusion sites in vivo, with a comparable rate of fusion with syngeneic bone graft (negative [0 of 10], BGS alone [0 of 10], bone graft [7 of 10], BGS+OEhMSC [10 of 15], and BGS+hBM [8 of 8]). CONCLUSIONS: Collectively, these studies demonstrate that BGS+OEhMSC constructs possess low immunogenicity and drive vertebral fusion with efficiency matching syngeneic bone graft in rodents. We also demonstrate that BGS serves as a promising scaffold for spine fusion when combined with hBM.

Internal fixation without fusion of a flexion-distraction injury in the lower cervical spine of a three-year-old.

BACKGROUND: Reported surgical treatment of unstable pediatric cervical spine injuries typically involves posterior fusion with internal fixation, usually with posterior wiring. PURPOSE: To discuss management issues in the treatment of an unstable Salter-Harris type I pediatric cervical spine injury and surgical intervention without fusion. STUDY DESIGN: A case report. METHODS: Summary of the management of an unstable flexion-distraction injury in a 3-year-old child is presented with literature review. RESULTS: A rare unstable flexion distraction injury of the pediatric cervical spine was successfully treated with posterior wiring without fusion. The wires underwent fatigue failure and maintenance of motion achieved without instability at 2-year follow-up. CONCLUSIONS: In select physeal injuries of the pediatric cervical spine, internal fixation can provide stability while healing occurs, with avoidance of fusion and maintenance of motion.

Optimization of Scaffolds and Surface-Based Treatments for Orthopedic Applications.

Improving spinal fusion by optimizing scaffold and surface engineering is a topic of interest for both surgeons and researchers. Concerns regarding patient safety with off-label use of bone morphogenetic protein (BMP) have increased, and patients are choosing minimally invasive spine surgery to lessen morbidity by avoiding harvest of bone graft. These trends may be driving studies on how surgeons can avoid issues associated with biologics (e.g., cost, morbidity), while achieving efficacious and safe bone fusion.

The Relationship of Obesity to Increasing Health-Care Burden in the Setting of Orthopaedic Polytrauma.

BACKGROUND: With the rise of obesity in the American population, there has been a proportionate increase of obesity in the trauma population. The purpose of this study was to use a computed tomography-based measurement of adiposity to determine if obesity is associated with an increased burden to the health-care system in patients with orthopaedic polytrauma. METHODS: A prospective comprehensive trauma database at a level-I trauma center was utilized to identify 301 patients with polytrauma who had orthopaedic injuries and intensive care unit admission from 2006 to 2011. Routine thoracoabdominal computed tomographic scans allowed for measurement of the truncal adiposity volume. The truncal three-dimensional reconstruction body mass index was calculated from the computed tomography-based volumes based on a previously validated algorithm. A truncal three-dimensional reconstruction body mass index of <30 kg/m(2) denoted non-obese patients and ≥ 30 kg/m(2) denoted obese patients. The need for orthopaedic surgical procedure, in-hospital mortality, length of stay, hospital charges, and discharge disposition were compared between the two groups. RESULTS: Of the 301 patients, 21.6% were classified as obese (truncal three-dimensional reconstruction body mass index of ≥ 30 kg/m(2)). Higher truncal three-dimensional reconstruction body mass index was associated with longer hospital length of stay (p = 0.02), more days spent in the intensive care unit (p = 0.03), more frequent discharge to a long-term care facility (p < 0.0002), higher rate of orthopaedic surgical intervention (p < 0.01), and increased total hospital charges (p < 0.001). CONCLUSIONS: Computed tomographic scans, routinely obtained at the time of admission, can be utilized to calculate truncal adiposity and to investigate the impact of obesity on patients with polytrauma. Obese patients were found to have higher total hospital charges, longer hospital stays, discharge to a continuing-care facility, and a higher rate of orthopaedic surgical intervention.

Bone regeneration with osteogenically enhanced mesenchymal stem cells and their extracellular matrix proteins.

Although bone has remarkable regenerative capacity, about 10% of long bone fractures and 25% to 40% of vertebral fusion procedures fail to heal. In such instances, a scaffold is employed to bridge the lesion and accommodate osteoprogenitors. Although synthetic bone scaffolds mimic some of the characteristics of bone matrix, their effectiveness can vary because of biological incompatibility. Herein, we demonstrate that a composite prepared with osteogenically enhanced mesenchymal stem cells (OEhMSCs) and their extracellular matrix (ECM) has an unprecedented capacity for the repair of critical-sized defects of murine femora. Furthermore, OEhMSCs do not cause lymphocyte activation, and ECM/OEhMSC composites retain their in vivo efficacy after cryopreservation. Finally, we show that attachment to the ECM by OEhMSCs stimulates the production of osteogenic and angiogenic factors. These data demonstrate that composites of OEhMSCs and their ECM could be utilized in the place of autologous bone graft for complex orthopedic reconstructions.

Mechanical bone strength of the tibial resection surface at increasing distance from the joint line in total knee arthroplasty.

Few articles have addressed the bone strength of the proximal tibia. This study attempts to quantify the compressive strength of bone in the proximal tibia of human cadaveric knees at increasing distance from the joint surface. Sixteen fresh-frozen human cadaveric knees were tested. The proximal tibia was sequentially sectioned into 1-cm slices, starting 2 mm below the chondral surface of the medial tibial plateau. Four slices were obtained from each knee. Each slice was then loaded to failure under an axial load. The proximal slice of bone had a significantly higher average maximum load to failure than the more distal slices. The second, third, and fourth slices of bone withstood 77%, 61%, and 73% of the average load of the proximal slice, respectively. This study was designed to simulate how the proximal tibia is loaded under an uncemented tibial base plate after total knee arthroplasty. The results are in agreement with previous studies that have shown the proximal 1 cm of tibial bone to have the highest resistance to compressive loads. Previous studies on the bone strength of the proximal tibia have focused on more proximal portions of bone than the current study. This study demonstrates that the load to failure of tibial resection surface decreases significantly with increasing distance from the joint line until the 4th cm of bone beneath the joint line is encountered. This information may play a role in surgical decision making and implant design.

Intrawound vancomycin powder reduces surgical site infections in posterior cervical fusion.

STUDY DESIGN: Retrospective comparative study using prospectively collected data. OBJECTIVE: To compare the rate of infection with and without the use of vancomycin powder application during posterior cervical instrumentation. SUMMARY OF BACKGROUND DATA: Surgical site infections (SSI) are a significant source of morbidity in multilevel posterior-instrumented fusions for cervical spondylotic myelopathy (CSM). Local delivery of antibiotics has been associated with decreased rates of SSI in posterior-instrumented fusions, but no study has addressed the effects of these measures on a population composed of exclusively multilevel posterior cervical instrumentation performed with decompression for CSM. METHODS: All patients undergoing multilevel posterior decompression and instrumentation for CSM by a single surgeon from 2003-2011 were included. Post hoc analysis of prospectively collected data was analyzed comparing consecutive patients treated without the use of vancomycin powder with those treated after the initiation of vancomycin powder prophylaxis. Intervention cohort and controls were examined for differences in SSI rate, body mass index, neurological status, comorbidities, and complications. RESULTS: A total of 112 patients were included in the study. Intervention (n = 40) and control (n = 72) groups were statistically similar with regard to age, body mass index, comorbidities, estimated blood loss, and operative time. Univariate analysis showed a significant decrease in infection rate in the intervention group (0%) compared with the control group (15%) in this high-risk population (P = 0.007; power = 81%). No adverse events were noted in the intervention group associated with the use of vancomycin powder. CONCLUSION: The local application of vancomycin was associated with a significant reduction in the risk of SSI in multilevel posterior cervical-instrumented fusions for CSM. This study supports the growing body of evidence that vancomycin powder placed in the wound can reduce the incidence of postoperative wound infections, and is the first that addresses this specific population. LEVEL OF EVIDENCE: 2.

The significance of facet joint cross-sectional area on magnetic resonance imaging in relationship to cervical degenerative spondylolisthesis.

BACKGROUND CONTEXT: Characteristic changes of the facet joints, including synovial cysts, facet joint hypertrophy, and facet joint effusions, on magnetic resonance imaging (MRI) and computed tomography have been associated with lumbar degenerative spondylolisthesis. The cervical facets have not been examined for associations with cervical degenerative spondylolisthesis similar to those seen in the lumbar spine. PURPOSE: To define abnormalities of the facet joints seen on supine MRI that correlate with cervical spondylolisthesis seen on upright radiographs. STUDY DESIGN: Retrospective radiographic review of consecutive patients with a universally applied standard. PATIENT SAMPLE: A total of 204 consecutive patients from a single institution, with both an MRI and upright radiographs, were reviewed. OUTCOME MEASURES: Sagittal plane displacement on upright lateral radiographs was compared with MRI. The total area of the facet joint and the amount of facet joint asymmetry were measured on an axial MRI. METHODS: The data were analyzed to determine a significant association between the cervical degenerative spondylolisthesis and the following: facet joint asymmetry, increased total area of the facet joint, and age. RESULTS: Degenerative spondylolisthesis was seen in 26 patients at C3-C4 and in 27 patients at C4-C5. Upright radiographs identified significantly more degenerative spondylolisthesis than MRIs at levels C3-C4 and C4-C5, 26 versus 6 (p<.001) at C3-C4 and 27 versus 11 (p<.001) at C4-C5. Patients with degenerative spondylolisthesis were more likely to be older, have a larger total facet area, and more facet asymmetry at C3-C4 and C4-C5 (p<.05). CONCLUSIONS: Supine MRIs underestimate sagittal displacement compared with upright lateral radiographs. Asymmetric facet hypertrophy at C3-C4 and C4-C5 is associated with degenerative spondylolisthesis on upright lateral films even in the absence of anterolisthesis on supine MRIs.

Short Term Culture of Human Mesenchymal Stem Cells with Commercial Osteoconductive Carriers Provides Unique Insights into Biocompatibility.

For spinal fusions and the treatment of non-union fractures, biological substrates, scaffolds, or carriers often are applied as a graft to support regeneration of bone. The selection of an appropriate material critically influences cellular function and, ultimately, patient outcomes. Human bone marrow mesenchymal stem cells (BMSCs) are regarded as a critical component of bone healing. However, the interactions of BMSCs and commercial bone matrices are poorly reported. BMSCs were cultured with several commercially available bone substrates (allograft, demineralized bone matrix (DBM), collagen, and various forms of calcium phosphates) for 48 h to understand their response to graft materials during surgical preparation and the first days following implantation (cell retention, gene expression, pH). At 30 and 60 min, bone chips and inorganic substrates supported significantly more cell retention than other materials, while collagen-containing materials became soluble and lost their structure. At 48 h, cells bound to ß-tricalcium phosphate-hydroxyapatite (ßTCP-HA) and porous hydroxyapatite (HA) granules exhibited osteogenic gene expression statistically similar to bone chips. Through 24 h, the DBM strip and ßTCP-collagen became mildly acidic (pH 7.1-7.3), while the DBM poloxamer-putties demonstrated acidity (pH < 5) and the bioglass-containing carrier became basic (pH > 10). The dissolution of DBM and collagen led to a loss of cells, while excessive pH changes potentially diminish cell viability and metabolism. Extracts from DBM-poloxamers induced osteogenic gene expression at 48 h. This study highlights the role that biochemical and structural properties of biomaterials play in cellular function, potentially enhancing or diminishing the efficacy of the overall therapy.

The use of routine thoracoabdominal CT scans in the polytrauma patient to estimate obesity.

OBJECTIVE: To utilize data from routine CT scans to quantify obesity in polytrauma patients without the need to obtain a height and weight. DESIGN AND METHODS: We utilized a comprehensive database including multidetector CT thoracoabdominal images of all polytrauma patients admitted to a Level 1 trauma center. One thousand one hundred seventy-four patients were reviewed from 2006 to 2008 and of these, 162 had previous documentation of Body Mass Index (BMI) or height and weight measurements as an outpatient within 6 months of trauma activation and with a truncal girth smaller than the scanning area of the CT machine. Truncal Adiposity Volume (TAV) was calculated from three dimensional reconstructions (3DRs) of the CT scans of the thorax and abdomen obtained in the emergency department. RESULTS: Statistical analysis yielded a fairly good correlation between TAV and BMI (correlation coefficient = 0.77; p-value < 0.0001). The intra-observer and inter-observer correlations in measuring TAV were high; 0.99 and 0.98 respectively. A linear regression equation of BMI on TAV was estimated and it had a form: 3DR BMI = 20.81+0.00064×TAV. In conclusion, TAV provides a reproducible means of evaluating obesity in trauma patients from routinely obtained CT scans. CONCLUSIONS: The TAV eliminates the often problematic task of obtaining a height and weight in a trauma patient and it correlates fairly well with the most commonly used clinical method of quantifying patient adiposity, BMI. This method may provide a more direct measurement of adiposity than does BMI, and holds promise for improving trauma care and research in the obese patient.

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.

No correlation between stroke specialty and rate of shoulder pain in NCAA men swimmers.

PURPOSE: To established an association between shoulder pain and the stroke specialization among NCAA men swimmers. MATERIALS AND METHODS: All members of the top 25 NCAA men's swim teams were invited to complete the survey. Eleven teams with a total of 187 participants completed the study survey. The teams were mailed surveys that included multiple choice questions regarding their primary stroke and their incidence of shoulder pain. Additionally, the survey included questions about risk factors including distance trained, type of equipment, weight training, and stretching. RESULTS: The analysis showed that there was no significant difference in the rates of shoulder pain among the four strokes and individual medley specialists. The other risk factors did not show a significant correlation with shoulder pain. CONCLUSIONS: This study found no significant correlation between stroke specialty and shoulder pain in male collegiate swimmers. LEVEL OF EVIDENCE: Level 3. CLINICAL RELEVANCE: Descriptive epidemiology study.