Study Design. An electrophysiologic and histologic study on nerve roots after mechanical compression and/or local application of nucleus pulposus (NP) was performed. Objective. To assess the effects of mechanical compression and/or chemical irritation caused by NP. Summary of Background Data. It has been shown that application of NP to nerve roots without compression induces histologic and functional changes in nerve roots and the dorsal root ganglia. In clinical situations, however, mechanical compression has also been considered an important factor in disc herniation. Methods. Eighteen dogs (9–15 kg) were used in this study. Four groups were used to assess the effect of each factor: 1) sham group (n = 3); 2) NP group (NP applied under the S1 lamina) (n = 5); 3) comp group (a plastic balloon placed under the S1 lamina) (n = 5); and 4) comp+NP group (a balloon and NP placed under the S1 lamina) (n = 5). Ascending cauda equina action potentials (CEAPs) and cauda equina–sensory nerve conduction velocity (SCV) were recorded before, immediately after, and 1 week after treatment. Histologic changes were also assessed by light microscopy. Results. There were no significant differences in CEAP and SCV among the four groups immediately after the treatment. However, 1 week after treatment, the amplitudes in the NP group, comp group, and comp+NP group were statistically significantly lower compared with those in the sham group. The comp+NP group showed significantly lower amplitude than did the NP group and comp group. Immediately after treatment, SCV in the NP group and comp group did not show significant differences compared with that in the sham group. However, 1 week after treatment, SCV in the comp+NP group was significantly lower compared with that in the sham group. Histologic changes such as intraneural edema, Schwann cell edema, and nerve fiber injury seemed to be more pronounced in the comp+NP group than in the other groups. Conclusions. It was shown that each of the assessed factors induces nerve dysfunction. However, the combination of mechanical compression (mass effect of herniated NP) and chemical irritation (inflammation around nerve root) may induce more nerve root injury than each factor per se.

Therapy for chronic, nonspecific low back pain is mainly conservative: medication and/or exercise. Pharmacotherapy, however, has side effects, and the quantities of concomitant drugs in older persons require attention. Although exercise promises improved function, its use to alleviate pain is controversial. Thus, we compared the efficacy of pharmacotherapy versus exercise for treating chronic nonspecific low back pain. The pharmacotherapy group (n=18: 8 men, 10 women) were prescribed celecoxib monotherapy. The exercise group (n=22: 10 men, 12 women) undertook stretching exercises. Because of drop-outs, the NSAID group (n=15: 7 men, 8 women) and the exercise group (n =18: 8 men, 10 women) were finally analyzed. We applied a visual analog scale, Roland-Morris disability scores, and the 36-Item Short Form Health Survey. We used a paired t-test for within-group analyses and an unpaired t-test for between-group analyses. Pain relief was achieved after 3 months of pharmacotherapy or exercise. Quality of life improved only in the exercise group. Recovery outcomes for the two groups were not significantly different. Efficacy of exercise therapy for strictly defined low back pain was almost equivalent to that of pharmacotherapy and provided better quality of life.

Introduction: Multidisciplinary pain management is a useful method for treating chronic musculoskeletal pain. Currently, few facilities in Japan offer multidisciplinary pain treatment, especially in the inpatient setting. We implemented a multidisciplinary pain management program based on International Association for the Study of Pain recommendations. This study described our initial efforts in implementing the program, and reported 3- and 6-month follow-up results. Materials and methods: Our pain management team included orthopedic surgeons, psychiatrists, nurses, physical therapists, clinical psychologists, pharmacists, and nutritionists. The 3-week inpatient pain management program comprised exercise therapy, psychotherapy, and patient education. We evaluated patients using the Brief Pain Inventory (BPI), Pain Catastrophizing Scale (PCS), Pain Disability-Assessment Scale (PDAS), Hospital Anxiety and Depression Scale (HADS), Pain Self-Efficacy Questionnaire (PSEQ), EuroQol Five Dimensions (EQ-5D), and physical examinations (flexibility, muscle endurance, walking ability, and physical fitness). Statistical analyses were performed using paired t-tests and Wilcoxon matched-pairs signed-rank sum tests with Bonferroni correction after the Friedman test. Results: Data for 23 patients were analyzed before and immediately after the program. Statistically significant improvements were seen in BPI, PCS, PDAS, HADS, PSEQ, EQ-5D, flexibility, muscle endurance, walking ability, and physical fitness. Eight patients were also assessed 3 and 6 months after the program. PCS (rumination and helplessness) scores and flexibility showed significant improvement at 3 and 6 months. Significant improvement was seen in PDAS and HADS (anxiety) scores and muscle endurance at 6 months, and in PSEQ scores immediately and at 3 and 6 months. Conclusion: Our inpatient pain management program can improve patients’ physical function and ability to cope with chronic musculoskeletal pain, which supports improved quality of life. Our program is currently being expanded to better assist patients with chronic musculoskeletal pain.

The gait-loading test is a well known, important test with which to assess the involved spinal level in patients with lumbar spinal stenosis. The lumbar extension-loading test also functions as a diagnostic loading test in patients with lumbar spinal stenosis; however, its efficacy remains uncertain. The purpose of this study was to compare the diagnostic value of the lumbar extension-loading test with that of the gait-loading test in patients with lumbar spinal stenosis.

Introduction: Multidisciplinary pain management is a useful method to treat chronic musculoskeletal pain. Few facilities in Japan administer a multidisciplinary pain management program, especially an inpatient program. Therefore, we implemented a multidisciplinary pain management program in our hospital based on biopsychosocial factors guided by the recommendations of the International Association for the Study of Pain. The purpose of this study is to describe our inpatient pain management program for Japanese patients, which uses the biopsychosocial method of pain self-management. Materials and methods: Fourteen patients with intractable chronic musculoskeletal pain, who were implemented a multidisciplinary pain management program in our hospital, were studied using the evaluation of the pain and associated factors and physical function. Results: Significant improvement in outcomes were seen in the brief pain inventory, the pain catastrophizing scale (rumination, magnification, and helplessness), the pain disability assessment scale, the hospital anxiety and depression scale (anxiety and depression), the pain self-efficacy questionnaire, the EuroQol five dimensions questionnaire, and muscle endurance and physical fitness. We found no statistically significant differences in static flexibility or walking ability. Conclusion: We developed an inpatient chronic pain management program for Japanese patients. Our results suggest that our program improves chronic musculoskeletal pain coping mechanisms, and that the program can improve patients’ quality of life and some physical function. This inpatient pain management program is being expanded to better help intractable chronic musculoskeletal pain patients.

The pathological mechanisms of lumbar spinal stenosis are unclear. Family doctors in the primary care setting may perform medical examinations of patients with lumbar spinal stenosis. Our aim was to use the painDETECT questionnaire to quantify the pathological mechanisms of low back pain and/or leg pain caused by lumbar spinal stenosis. We enrolled 102 patients (37 men, 65 women) who had been newly diagnosed with lumbar spinal stenosis at 2 facilities. The patients’ conditions were evaluated using the painDETECT questionnaire, Numerical Rating Scale, Roland-Morris Disability Questionnaire, Japanese Orthopaedic Association Back Pain Evaluation Questionnaire, and 36-Item Short-Form Health Survey. The pathological mechanisms of low back pain and/or leg pain caused by lumbar spinal stenosis were classified based on results of the painDETECT questionnaire as nociceptive pain, neuropathic pain, or unclear type of pain (mixed pain). Statistical analyses were performed using the Kruskal–Wallis test. A value of p < 0.05 was considered to indicate statistical significance. The mean age of all patients in this study was 70.3 ± 2 years. The male:female distribution was 37:65 (36.3:63.7 %). In all, 72 (70.6 %) patients had chronic pain (duration of ≥3 months), and 30 (29.4 %) had subacute or acute pain (duration of <3 months). The pain was classified as nociceptive in 59 patients (57.9 %), neuropathic in 18 (17.6 %), and unclear in 25 (24.5 %). The neuropathic pain group had a significantly lower quality of life (p < 0.05) than did the other groups. Patients with neuropathic back and/or leg pain caused by lumbar spinal stenosis may have lower physical and/or psychological quality of life than patients with such pain caused by other mechanisms.