Association between Postoperative Neck Pain and Intraoperative Transcranial Motor-Evoked Potential Waveforms of the Trapezius Muscles in Patients with Cervical Myelopathy Who Underwent Cervical Laminoplasty

Methods@#A total of 79 patients with cervical myelopathy who underwent cervical laminoplasty at our facility between June 2010 and March 2013 were included in this study. Intraoperative control and final waveform were evaluated based on the trapezius muscle MEPs by measuring the latency and amplitude. A neck pain group comprised patients with higher neck pain Visual Analog Scale scores from preoperative value to 1 year postoperatively. The cross-sectional areas of the trapezius muscles and the MEP latencies and amplitudes were compared between patients with and without neck pain. @*Results@#The latency and amplitude of the control waveforms were not significantly different between groups. The neck pain group had a significantly shorter final waveform latency (neck pain: 23.6±2.5, no neck pain: 25.8±4.5; p =0.019) and significantly larger amplitude (neck pain: 2,125±1,077, no neck pain: 1,630±966; p =0.041) than the no neck pain group. @*Conclusions@#Postoperative neck pain was associated with the final waveform latency and amplitude of the trapezius muscle MEPs during cervical laminoplasty. Intraoperative electrophysiological trapezius muscle abnormalities could cause postoperative neck pain.

Evaluation of the Association between Neck Pain and the Trapezius Muscles in Patients with Cervical Myelopathy Using Motor Evoked Potential: A Retrospective Study

Methods@#The study included 100 patients with cervical myelopathy who underwent surgery at the National Center for Geriatrics and Gerontology in Obu, Japan from June 2010 to March 2013. Before the surgery, neck pain was evaluated using a Visual Analog Scale (a score ≥50 indicated neck pain and a score <50 indicated no neck pain). The preoperative cross-sectional areas of the trapezius muscles were measured with cervical magnetic resonance imaging sagittal T2-weighted images. Cranial stimulation under general anesthesia was used to derive the MEPs, enabling the measurement of latency and amplitude, using preoperative MEPs of the trapezius muscles. @*Results@#The MEP of the trapezius muscle in patients with neck pain had significantly shorter latencies than those in patients who did not have neck pain. However, there was no significant difference in the amplitude between patients with and without neck pain. However, this tended to be greater in patients with neck pain as compared to that in those without neck pain. The cross-sectional area of the trapezius muscle in patients with neck pain was significantly smaller than that in those who did not have neck pain. @*Conclusions@#MEPs revealed electrophysiological abnormalities of the trapezius muscles in patients with neck pain, supporting a relationship of neck pain with the trapezius muscles.

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.

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 wholebody 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.

Neuropathic Pain in Elderly Patients with Chronic Low Back Painand Effects of Pregabalin: A Preliminary Study

STUDY DESIGN: Preliminary study. PURPOSE: To assess the association of neuropathic pain with chronic low back pain (LBP) and the effect of pregabalin on neuropathic pain in the elderly. OVERVIEW OF LITERATURE: Of those with chronic LBP, 37% were predominantly presenting with neuropathic pain in young adults. Pregabalin is effective for pain in patients with diabetic neuropathy and peripheral neuralgia. No study has reported on the effects of pregabalin for chronic LBP in elderly patients yet. METHODS: Pregabalin was administered to 32 patients (age, > or =65 years) with chronic LBP for 4 weeks. Pain and activities of daily living were assessed using the Neuropathic Pain Screening Questionnaire (NePSQ), the pain DETECT questionnaire, visual analog scale, the Japanese Orthopedic Association score, the short form of the McGill Pain Questionnaire and the Roland Morris Disability Questionnaire. Modic change and spinal canal stenosis were investigated using magnetic resonance imaging. RESULTS: Altogether, 43.3% of patients had neuropathic pain according to the NePSQ and 15.6% patients had pain according to the pain DETECT. The efficacy rate of pregabalin was 73.3%. A significant effect was observed in patients with neuropathic pain after 4 weeks of administration. CONCLUSIONS: Neuropathic pain was slightly less frequently associated with chronic LBP in the elderly. Pregabalin was effective in reducing pain in patients with chronic LBP accompanied with neuropathic pain. Lumbar spinal stenosis and lower limb symptoms were observed in patients with neuropathic pain. We recommend the use of pregabalin for patients after evaluating a screening score, clinical symptoms and magnetic resonance imaging studies.

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

STUDY DESIGN: Animal study. PURPOSE: To 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 LITERATURE: Little is known about correlation palesis and amplitude of spinal cord monitoring. METHODS: After 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. RESULTS: Four 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. CONCLUSIONS: Amplitude and morphology change of the CMAP wave exists and could be the key of the alarm point in CMAP.