Analysis of hip geometry by clinical CT for the assessment of hip fracture risk in elderly Japanese women.

Two case-control studies were designed to investigate the contribution of the geometry and bone mineral density (BMD) of the proximal femur to bone strength in Japanese elderly women. We also investigated whether clinical CT is useful to assess the risk of hip fracture. Subjects in the neck fracture study included 20 Japanese women with neck fracture (age: mean+/-SD; 80.1+/-4.5 years old) and 20 age-matched control women (79.2+/-2.6 years old). Subjects in the trochanteric fracture study included 16 Japanese women with trochanteric fracture (82.6+/-5.0 years old) and 16 age-matched control women (80.8+/-3.8 years old). CT examination of the proximal femur was performed between the date of admission and the date of surgery. The CT scanners used were an Aquillion 16 (Toshiba) and Somatom 64 (Siemens); the scanning conditions including spatial resolution and scanning energy were adjusted, and the same type of reference phantom containing hydroxyapatite was used. QCT PRO software (Mindways) was used to analyze data for BMD, geometry, and biomechanical parameters. Both the neck and trochanteric fracture cases had significantly lower total and cortical BMD, a significantly smaller cortical cross-sectional area (CSA), and a larger trabecular CSA. Both had significantly thinner cortex and smaller distance to center of bone mass, and women with trochanteric fracture had a significantly smaller cortical perimeter in the cross-sectional femoral neck. Women with neck fracture had a longer hip axis length (HAL) and women with trochanteric fracture had a significantly larger neck-shaft angle (NSA). Both groups had significantly lower cross-sectional moment of inertia (CSMI), and only women with neck fracture had a significantly higher buckling ratio (BR) compared to their respective controls. According to the multiple logistic regression analysis, women with neck fracture had a significantly longer HAL, lower CSMI, and higher BR, and women with trochanteric fracture had a significantly smaller cortical CSA of the femoral neck. We conclude that clinical CT may be useful for the assessment of the risk of neck and trochanteric fracture

Variety of the Wave Change in Compound Muscle Action Potential in an Animal Model

Study DesignAnimal study.PurposeTo review the present warning point criteria of the compound muscle action potential (CMAP) and investigate new criteria for spinal surgery safety using an animal model.Overview of LiteratureLittle is known about correlation palesis and amplitude of spinal cord monitoring.MethodsAfter laminectomy of the tenth thoracic spinal lamina, 2-140 g force was delivered to the spinal cord with a tension gage to create a bilateral contusion injury. The study morphology change of the CMAP wave and locomotor scale were evaluated for one month.ResultsFour different types of wave morphology changes were observed: no change, amplitude decrease only, morphology change only, and amplitude and morphology change. Amplitude and morphology changed simultaneously and significantly as the injury force increased (p<0.05) Locomotor scale in the amplitude and morphology group worsened more than the other groups.ConclusionsAmplitude and morphology change of the CMAP wave exists and could be the key of the alarm point in CMAP

Effects of Image Processing Using Honeycomb-Removal and Image-Sharpening Algorithms on Visibility of 27-Gauge Endoscopic Vitrectomy

Endoscopic vitrectomy with small gauge probes has clinical potentials, but intraocular visibility is inherently limited by low resolution and dim illumination due to the reduced number of optic fibers. We investigated whether honeycomb-removal and image-sharpening algorithms, which enable real-time processing of live images with a delay of 0.004 s, can improve the visibility of 27-gauge endoscopic vitrectomy. A total of 33 images during endoscopic vitrectomy were prepared, consisting of 11 original images, 11 images after the honeycomb-removal process, and 11 images after both honeycomb-removal and image-sharpening procedures. They were randomly presented to 18 vitreous surgeons, who rated each image on a 10-point scale. The honeycomb-removal algorithm almost completely suppressed honeycomb artifacts without degrading the background image quality. The implementation of image-sharpening algorithms further improved endoscopic visibility by optimizing contrast and augmenting image clarity. The visibility score was significantly improved from 4.27 &plusmn; 1.78 for the original images to 4.72 &plusmn; 2.00 for the images after the honeycomb-removal process (p &lt; 0.001, linear mixed effects model), and to 5.40 &plusmn; 2.10 for the images after both the honeycomb-removal and image-sharpening procedures (p &lt; 0.001). When the visibility scores were analyzed separately for 10 surgeons who were familiar with endoscopic vitrectomy and 8 surgeons who were not, similar results were obtained. Image processing with honeycomb-removal and image-sharpening algorithms significantly improved the visibility of 27-gauge endoscopic vitrectomy

Low Back Pain in Patients with Lumbar Spinal Stenosis―Hemodynamic and electrophysiological study of the lumbar multifidus muscles

Introduction: Several studies have demonstrated improvement in low back pain (LBP) after decompression surgery for lower extremity symptoms in lumbar spinal stenosis (LSS); however, the influence of neuropathic disorders on LBP is uncertain. Aim of this study is to identify the features of motion-induced and walking-induced LBP in patients with LSS and to assess whether neuropathic LBP develops. Methods: In total, 234 patients with LSS including L4/5 lesion were asked to identify their LBP. Subjects were classified into three groups: walking-induced LBP that aggravated during walking (W group), motion-induced LBP that aggravated during sitting up (M group), and no LBP (N group). Cross-sectional areas of the dural sac, lumbar multifidus, and the erector spinae were measured. Intramuscular oxygenation was evaluated with near-infrared spectrophotometer. Surface electromyography (EMG) and mechanomyography (MMG) were performed on the lumbar multifidus. Morphological, hemodynamic, and electrophysiological differences in the onset of LBP were evaluated. Results: The prevalence of W, M, and control groups was 31.2%, 32.1%, 36.8%, respectively. Concordance between the laterality of LBP and leg symptoms including pain and numbness was 86.3% in the W group and 47.0% in the M group. Dural sac area was lower in the W group than in the M and control groups. In the hemodynamic evaluation, the oxygenated hemoglobin level was significantly lower in the W group than in the M and N groups. In electrophysiological evaluation of lumbar multifidus, the mean power frequency in EMG was significantly higher in the W group than in the N group. Amplitude in MMG was significantly lower in the W group than in the N group. Conclusions: Neurologic disturbance in patients with LSS may be attributed to “neuropathic LBP.” Neuropathic multifidus disorder plays a role in walking-induced LBP

Sarcopenia in elderly patients with chronic low back pain

Objectives: The prevalence of chronic low back pain (CLBP) increases with age and several mechanisms are involved in the development of CLBP, including osteoporosis; however, no associations with sarcopenia have yet been identified. Methods: In total, 100 patients with CLBP and 560 patients without CLBP (nCLBP) aged over 65 years were studied. Skeletal muscle mass index (SMI) and percentage of body fat were evaluated using whole-body dual-energy X-ray absorptiometry. Sarcopenia was diagnosed when the relative SMI was more than 2 standard deviations below the mean in young adults. Thus, the cutoff value for sarcopenia was defined according to Sanada's Japanese population data. Paraspinal muscle cross-sectional areas of the lumbar multifidus and the erector spinae muscles were calculated using magnetic resonance imaging. Results: Forty patients (40.0%) from the CLBP group and 149 (26.6%) from the nCLBP group met the criteria of sarcopenia. SMI was significantly lower and the body fat ratio was significantly higher in the CLBP group compared with the nCLBP group. Sarcopenic obesity was significantly observed in the CLBP group. Lumbar multifidus and the erector spinae muscle cross sectional area were significantly lower in the CLBP group. Conclusions: Elderly patients with CLBP have significantly lower skeletal muscle mass, and age-related mechanisms in sarcopenia are considered to be associated with chronic pain. Therapeutic procedures that are used to treat elderly aging muscle, including muscle strengthening and performance training, can possibly be a treatment for or used to prevent elderly CLBP

Sarcopenia affects conservative treatment of osteoporotic vertebral fracture

Objectives: Sarcopenia and osteoporosis affects activities of daily living and quality of elderly people. However, little is known about its impact on elderly locomotor diseases, such as osteoporotic vertebral fracture (OVF). There is no report investigating the influence of both sarcopenia and osteoporosis on outcomes of OVF. This study aimed to evaluate the clinical outcomes of OVF in elderly patients from sarcopenic perspectives. Methods: This prospective study was conducted with 396 patients, aged 65 years or more, hospitalized for the treatment of OVF (mean age, 81.9 ± 7.1 years; 111 males, 285 females). The primary outcome was the Japanese Orthopaedic Association (JOA) score for lumbar disease (at first visit, hospital discharge, and 1 year after treatment) and Barthel index (at the same time and before hospitalization). The second outcome was living place after discharge. Susceptibility to sarcopenia and osteoporosis were evaluated and clinical results of conservative treatment were compared. Results: Sarcopenia significantly affected Barthel index at first visit and discharge. Sarcopenia patients had significantly higher rate for discharge to nursing home and living in nursing home after 1 year than patients without sarcopenia. Osteoporosis significantly affected the JOA score at the first visit and the Barthel index before hospitalization, at the first visit, discharge, and after 1 year. Osteoporosis did not affect the living place at discharge and after 1 year. Conclusions: Sarcopenia and osteoporosis affected outcomes of conservative treatment for OVF; moreover, sarcopenia affected the living place of OVF patients at discharge and after 1 year. Keywords: Sarcopenia, Vertebral fracture, Conservative treatmen