阿部 幸喜

BACKGROUND: The Japanese Orthopedic Association launched the Japanese Orthopedic Association National Registry (JOANR), Japan's first large-scale nationwide musculoskeletal disease registry, in 2020. The World Health Organization released the International Classification of Health Interventions (ICHI) Beta-3 version in the same year. This concurrence served as an impetus to examine the relationship between domestic and international classification for orthopedic interventions. Our objective was to evaluate the possibility of utilizing JOANR for international comparison and the potential usage of ICHI in the domestic medical fee reimbursement system. This study is a novel attempt at mapping a domestic orthopedic scheme to the ICHI. METHODS: We mapped 149 codes out of 581 orthopedic surgical codes, on JOANR's registration form, to the ICHI, and then classified the nature of JOANR codes' relationship, to both ICHI single stem codes and stem codes accompanied by other additional stem codes, extension codes, and International Classification of Diseases for Mortality and Morbidity Statistics (ICD) codes, into five categories: Equivalent (exact match), Narrower (compared to ICHI; can be smoothly incorporated into ICHI), Broader (compared to ICHI), Slipped (combination of both Narrower and Broader), and None (no appropriate code). Finally, debatable issues that arose during the mapping operation were noted. RESULTS: The domestic codes' relationship to ICHI single stem code by category were Equivalent: 27 (18.1%) and Narrower: 65 (43.6%), respectively. Further, the rate of Equivalent rose to 120 (80.5%) on adding other stem codes, extension codes, and ICD codes. Additionally, certain domestic titles, which were unsuitable for classification as they included diagnostic information, and arthroscopic surgeries without corresponding ICHI codes, were recoded. CONCLUSIONS: JOANR can be converted to an international comparison standard via ICHI to a certain extent, and ICHI accompanied by ICD codes has potential for deployment in the domestic medical fee reimbursement system.

Introduction Advanced glycation end-products (AGEs) have the potential to serve as biomarkers of aging and metabolic diseases; however, how their expression relates to clinical symptoms is not well defined. In this study, we sought to determine whether the accumulation of pentosidine, one type of AGE, at the peripheral nerve is associated with cutaneous pain or hypersensitivity caused by ovariectomy (OVX). Methods We assigned 12-week-old female Sprague Dawley rats into either the OVX group (n = 6) or the sham group (n = 6). Cutaneous hindpaw sensitivity to mechanical stimuli was measured with von Frey filaments, using Chaplan's adapted method, and the 50% withdrawal threshold was calculated. Then, the accumulation of pentosidine, which represents AGEs, was measured in sciatic nerve fibers after staining with an anti-pentosidine antibody. Results OVX rats showed significantly increased plantar hypersensitivity to mechanical stimuli compared to sham rats 8 weeks after OVX (P = 0.017). Pentosidine-positive sciatic nerves were detected at a higher rate in OVX rats than in sham rats (P = 0.035). The pentosidine positivity rate in sciatic nerve fibers showed a negative correlation with withdrawal threshold (P < 0.001). Conclusions This study showed that higher levels of pentosidine in sciatic nerve fibers are associated with higher plantar hypersensitivity. Accumulation of pentosidine at the sciatic nerve, caused by OVX, may result in cutaneous hindpaw hypersensitivity.

STUDY DESIGN: A retrospective observational study. PURPOSE: To compare two conservative treatments for acute osteoporotic vertebral fractures (OVFs). OVERVIEW OF LITERATURE: Several studies have reported conservative treatments for OVFs in terms of using a brace, rehabilitation, and bed rest. However, there is no consensus about the conservative treatment for OVFs. METHODS: We evaluated 68 patients with acute OVF treated in our hospital from 2007 to 2011. Thirty-four patients treated in prolonged bed rest (PBR) regimen underwent rehabilitation wearing a Jewett's brace after three weeks of bed rest. In contrast, the other 34 patients underwent rehabilitation wearing a Jewett's brace as soon as possible, which we called a stir-up (SU) regimen. We compared two treatment groups for medical costs, hospital length of stay (LOS), pain according to the numeric rating scale (NRS), the activities of daily living (ADL), and imaging studies. RESULTS: The average hospital LOS was significantly shorter in patients treated by the SU regimen, which resulted in the medical costs reduction. There was no significant difference in the NRS through 6 months between the two groups. Although many patients in both groups experienced at least one level reduction in ADL at 6 months after the injury, patients in the SU group tended to maintain their pre-injury ADL, which almost agrees with past reports. In terms of imaging studies, patients in the PBR group showed milder vertebral compression rate over time. Pseudoarthrosis occurred in 2 patients in the SU group, who presented with mild pain, which had little influence on their daily lives. CONCLUSION: We compared two conservative treatments for OVFs. Early rehabilitation was useful treatment for OVFs to minimize the risk for disuse syndrome, maintain pre-injury ADL status, and reduce the medical costs.

BACKGROUND: When treating cancer patients, the progression of symptoms is accompanied by the deterioration of systemic conditions and motor function. From a risk-benefit perspective, a certain level of physical function must be maintained to continue cancer treatment. Recently, outpatient cancer treatment has become more common. Motor function is important to determine the feasibility of continuing cancer treatment. The study aimed to evaluate the motor function of patients with visceral cancer using locomo tests established by Japanese Orthopaedic Association. METHODS: Locomo tests were performed, and the results were compared with data from non-cancer individuals. Background data were matched by propensity score matching. Data from 53 cancer patients (group C) were compared with that of 75 non-cancer patients (group N). RESULTS: The average score in the two-step test of group C was lower than that of group N (1.27: 1.37, p = 0.004). The average function in the stand-up test of group C was worse than that of group N (p = 0.001). The average score in the 25-question geriatric locomotive function scale (GLFS) of group C was significantly higher than that of group N (19.92: 5.29, SE 2.21, p < 0.001). Higher 25-question GLFS scores indicate reduced mobility. The proportion of the locomo stage 2 in group C was significantly higher than in group N (51%: 13%, p < 0.001). The results of the two field tests revealed a clinically minimal difference between the two groups, but a statistically significant difference. Locomo tests may be detect potential motor dysfunction in outpatient cancer patients with apparently maintained motor function. CONCLUSIONS: Even in cancer patients who attend outpatient clinics, their motor functions could be potentially impaired. Therapeutic interventions to maintain and enhance motor function for cancer patients could be useful for continuing cancer treatment, and furthermore, improving prognosis.

The aim of this study was to determine whether advanced glycation end products (AGEs) revealed by skin autofluorescence (SAF), serum and urine pentosidine level, and serum homocysteine level can serve as a biomarker for sarcopenia in older women. The participants were 70 elderly women. The AGEs pentosidine, homocysteine, and SAF were measured as aging markers. This study shows that among the biomarkers for aging, serum pentosidine correlates with a loss of appendicular lean mass and can serve as a biomarker for sarcopenia. Moreover, SAF and homocysteine values exhibited a positive correlation with age and correlated with each other.Abbreviations: AGEs: advanced glycation end products; BIA: bioelectrical impedance analyzer; BMD: bone mineral density; DLS: degenerative lumbar scoliosis; DXA: dual-energy X-ray absorptiometry; ELISA: enzyme-linked immunoassay; HHcy: hyperhomocysteinemia; RIA: radioimmunoassay; SAF: skin autofluorescence; SMI: skeletal muscle mass index; T2DM: type 2 diabetes patients.

OBJECTIVES: To examine improvement in acute low back pain (LBP) using ultrasound-guided hydrorelease of the multifidus muscle. METHODS: This prognostic cohort study was conducted in a private clinic on samples of 75 patients with acute LBP diagnosed based on physical and imaging findings. Hydrorelease of the multifidus muscle was performed at the L4/5 level. The LBP visual analog scale (VAS) scores (cm) before and 5 minutes after hydrorelease were statistically evaluated. We defined improvement rate (%) as {LBP VAS scores (cm) immediately before hydrorelease - LBP VAS scores (cm) 5 minutes after hydrorelease} × 100 / LBP VAS scores (cm) immediately before hydrorelease and examined the correlation of the Heckmatt score and average age with the improvement rate. RESULTS: LBP VAS scores (cm) before and 5 minutes after hydrorelease were 7.19 ± 1.01 (mean ± SD) and 2.85 ± 1.25, respectively (p < 0.05). No significant correlations were noted between the LBP improvement rate and the Heckmatt score or age. There were no gender variations in the improvement rate. CONCLUSIONS: Ultrasound-guided hydrorelease of the multifidus muscle led to considerable LBP VAS score improvement at the outpatient level. The improvement rate showed no correlations with the Heckmatt score or age, and there were no significant gender variations in the improvement rate. Therefore, fatty degeneration of muscles and change in muscle echogenicity due to age and gender may not be associated with muscular LBP. These findings suggest that multifidus muscle hydrorelease could be useful in the diagnosis and treatment of acute LBP.

STUDY DESIGN: Retrospective observational study. PURPOSE: Lumbar spinal stenosis (LSS) has traditionally been evaluated morphologically, there is a paucity of literature on quantitative assessment of LSS. The purpose of this study was to investigate whether intraspinal diffusion tensor imaging (DTI) parameters such as apparent diffusion coefficient (ADC) and fractional anisotropy (FA) are useful for assessing LSS. OVERVIEW OF LITERATURE: Quantitative assessment of LSS is challenging. METHODS: Study participants comprised five healthy volunteers (mean age, 27.2 years) and 27 patients with LSS (mean age, 58.4 years) who were individually assessed using 3.0 Tesla magnetic resonance imaging. Intraspinal ADC and FA values of 10 intervertebral discs from healthy volunteers and 52 intervertebral discs from LSS patients were measured. Also, intraspinal canal area, Schizas classification (A: normal, B: mild stenosis, C: severe stenosis) and correlations with symptoms were investigated. Clinical symptoms were checked for the presence of low back pain (LBP), intermittent claudication (IMC), and bladder and bowel dysfunction (BBD). RESULTS: Compared to healthy individuals, LSS patients had significantly lower ADC (p<0.05) and significantly higher FA values (p<0.01). In Schizas classification, stenosis worsened from A to C. ADC values decreased significantly while FA values increased significantly in that order (p<0.05). A positive correlation was found between intraspinal canal area and ADC values (r=0.63, p<0.01) and a negative correlation between intraspinal canal area and FA values (p=-0.61, p<0.01). No correlations were noted between LBP and ADC or FA values. On the other hand, ADC values were significantly lower (p<0.05) and FA values were significantly higher (p<0.05) in patients with IMC or BBD. CONCLUSIONS: Intraspinal DTI parameters such as ADC and FA values were associated with the Schizas classification, intraspinal canal area, and clinical symptoms, suggesting that ADC and FA may be useful for quantitative assessment of LSS.

OBJECTIVE: Laminoplasty is an effective procedure for treating cervical spondylotic myelopathy. We conduct myovascular preserving open-door laminoplasty (MPLP) in combination with a laminoplasty plate to improve the stability of the enlarged lamina. We compare the details of the MPLP technique with conventional open-door laminoplasty. METHODS: We compared 25 cases of MPLP (mean age = 70.5, mean follow-up period = 19 months) with 15 controls who received conventional open-door laminoplasty using hydroxyapatite spacers (mean age = 74, mean follow-up period = 53 months). Regarding surgical outcomes, blood loss, operative time, Japanese Orthopaedic Association score, and postoperative visual analog score for neck pain were measured. Regarding image analysis, preoperative and postoperative range of motion (ROM), C2-7 angle, implant back out, hinge bone fusion time, presence or absence of hinge bone union failure, and posterior neck fat infiltration rate were evaluated. RESULTS: Operative time was significantly shorter for MPLP, and postoperative neck pain was significantly decreased. In image evaluation, %ROM was significantly increased in MPLP, but no difference in C2-7 angle existed between the 2 groups. Implant back out was not recognized in either group. In MPLP, the hinge union period was significantly shortened, and the postoperative fat infiltration rate was significantly decreased. CONCLUSIONS: We were able to reduce neck pain after surgery by an approach entailing longitudinal splitting of the spinous processes. We were able to ensure shorter operation times due to cervical plates and better hinge bone fusion times due to initial stability. LEVEL OF EVIDENCE: 4.

STUDY DESIGN: Observational study. PURPOSE: To evaluate healthy volunteers and patients with spinal canal lesions using apparent diffusion coefficient (ADC) maps with diffusion-weighted imaging. OVERVIEW OF LITERATURE: Decompression surgery for lumbar spinal stenosis (LSS) is selected on the basis of subjective assessment and cross-sectional magnetic resonance imaging (MRI). However, there is no objective standard for this procedure. METHODS: We performed 3T MRI in 10 healthy volunteers and 13 patients with LSS. The ADC values in the spinal canal were evaluated at 46 vertebrae (L4/5 and L5/S1 for each participant), and the reduced and conventional fields of view were compared. RESULTS: The ADC values were 2.72±0.12 at L4/5 in healthy volunteers, 2.76±0.19 at L5/S1 in healthy volunteers, 1.77±0.58 at L4/5 in patients with LSS, and 2.35±0.29 at L5/S1 in patients with LSS. The ADC value at L4/5 in patients with LSS was significantly lower than that at L5/S1 in patients with LSS and that at L4/5 and L5/S1 in healthy volunteers (p <0.05). With an ADC cutoff value of 2.46 to identify LSS, this approach provided an area under the curve of 0.81, sensitivity of 0.92, and specificity of 0.76 (p <0.05). CONCLUSIONS: Preoperative examination using ADC maps permits visualization and quantification of spinal canal lesions, thus proving the utility of ADC maps in the selection of decompression surgery for LSS.

BACKGROUND: Lumbar spinal disease causes disabilities in performing daily activities. Operative treatments are aimed at pain relief and rapid return to routine activity. Patient-based outcome measures are used to evaluate pathologies and therapeutic effects associated with lumbar spinal disease. Nevertheless, it remains unknown as to how much such treatment improves activity levels. The purpose of the current study was to measure changes in activity levels before and after lumbar spinal surgery using a wearable activity tracker and to analyze the differences between results and patient-based outcomes. METHODS: Sixty patients who underwent lumbar surgery were studied. The physical activity of participants was objectively evaluated using a wearable Micro-Motion logger system (Actigraph). We measured the amount of activity before and at 1, 3, 6, and 12 months after the surgery to evaluate postoperative changes. The Japanese Orthopaedic Association Back Pain Evaluation Questionnaire, Oswestry Disability Index, Roland-Morris Disability Questionnaire and visual analog scale were used to assess patient-based outcomes of pain and activities of daily living-related scores; we analyzed the relationships between scores and actual activity levels. RESULTS: The amount of actual activity decreased significantly 1 month after the surgery compared to that during the preoperative period, which then improved after 3 months postoperatively (p < 0.01). Furthermore, there was a significant improvement 6 months after the surgery compared to that during the preoperative period (p < 0.05). The changes in activity for each period were strongly correlated, regardless of the period. In contrast, a significant improvement was observed at 1 month after the surgery in almost all items of the patient-based questionnaires (p < 0.05). CONCLUSIONS: The objective activity tracker demonstrated that lumbar surgery results in the amount of activity decreasing 1 month just after surgery followed by gradual postoperative recovery within 3 months. By contrast, patient-based outcomes showed improvement in 1 month that was significantly different from the change in actual activity, indicating a gap between patient-oriented clinical scores and their actual activities.

Introduction: There are several reports about invasive muscle injury during posterior spinal surgery. However, few reports have evaluated the association between the clinical symptoms and changes in the physical properties of the psoas major after oblique lateral interbody fusion (OLIF). Therefore, the current study aimed to investigate the relationship between the clinical symptoms and changes in the psoas major muscle before and after OLIF. Methods: Twenty-seven patients who underwent single-level OLIF following the diagnosis of degenerative lumbar disease were included in the study. The cross-sectional areas (CSAs) of the psoas major on the approaching and contralateral sides were measured in the axial computed tomography view of the surgical intervertebral space preoperatively and postoperatively at 1 week and 3, 6, and 12 months. The preoperative and postoperative changes in the CSAs were compared. Muscle degeneration was evaluated using axial magnetic resonance images at the same level as that in the CSA evaluation preoperatively and at 12 months postoperatively. Additionally, the relationship between these parameters and postoperative lower limb symptoms was investigated. Results: Significant swelling of the psoas major on the approach side was observed 1 week postoperatively (p < 0.05). No postoperative muscle degeneration was observed. Three cases of paresthesia in the front of the thigh were observed, but no association was found with changes in CSA in any of the cases. Conclusions: The OLIF approach caused swelling of the psoas major 1 week postoperatively with no more muscle degeneration in the mid-term. Although numbness of the lower limbs was found in some cases, no association was found with changes in CSA. Our study findings suggest that the OLIF approach causes temporary injury or swelling of the psoas major, but the long-term damage to the muscle is not significant.

STUDY DESIGN: Controlled laboratory study. PURPOSE: This study aimed to evaluate the in vitro pharmacological activity of growth factors (GFs) in freeze-dried platelet-rich plasma (FD-PRP) after storage for 4 weeks. OVERVIEW OF LITERATURE: Freshly prepared PRP is a rich source of many GFs. We reported that FD-PRP stored for 8 weeks accelerated bone union in a rat posterolateral fusion model equally well as fresh-PRP. However, the pharmacological activity of FD-PRP after longterm storage has not been shown in vitro. METHODS: Immediately after preparation, as well as 4 weeks after freeze-dried storage, the platelet count was measured. Human osteoblasts were treated with fresh-PRP and FD-PRP, respectively. Western blotting was used to assess the phosphorylation of the platelet-derived growth factor (PDGF) receptor (PDGFR) and its downstream target, extracellular signal-regulated kinase (ERK). The proliferation rates of osteoblasts were investigated by immunocytochemistry and MTT cell viability assays. Furthermore, we used western blotting to evaluate the effect of PDGFR knockdown on the phosphorylation of ERK stimulated with fresh-PRP and FD-PRP. RESULTS: Platelet counts in both the fresh-PRP and FD-PRP samples were approximately 10-fold higher than in peripheral blood samples. The phosphorylation and activation of the PDGFR and ERK were evenly induced by fresh-PRP and FD-PRP stimulation. Both freshPRP and FD-PRP significantly induced osteoblast proliferation in MTT cell viability assays. Furthermore, osteoblast PDGFR knockdown attenuated the downstream ERK activation by fresh PRP and FD-PRP. CONCLUSIONS: We demonstrated the pharmacological activity of PDGF in FD-PRP in vitro after 4 weeks of storage.

PURPOSES: To evaluate whether a relationship exists between patient-based scoring systems and the activity level of patients with low back pain (LBP) by using wearable activity trackers, and to determine whether activity level was affected by patient factors. METHODS: The subjects were 66 patients with LBP. The physical activity of participants was objectively evaluated using the Micro-Motion logger (Actigraph). The activity level was analyzed with the mean active count of the proportional-integrating mode (PMAC) and zero-crossing mode. Clinical symptoms were evaluated using the Japanese Orthopaedic Association Back Pain Evaluation Questionnaire (JOABPEQ), Roland-Morris Disability Questionnaire, the Oswestry Disability Index, and visual analog scale (VAS). The relationships between each item of the patient-based questionnaire and activity level, and the influence of individual factors (age, sex, body mass index [BMI], low back pain, and muscle mass) on the activity level were evaluated. RESULTS: In each domain of the JOABPEQ, lumbar spine dysfunction and social life dysfunction were correlated with PMAC (r = 0.327 and 0.321, respectively). The low back pain VAS scores were correlated with PMAC (r = - 0.246). Multiple regression analysis shows that individual factors affecting the activity level of patients with LBP were sex, BMI, low back pain, and muscle mass in PMAC (p < 0.01). CONCLUSIONS: Some domains of the questionnaires were correlated with activity level, but others were not. Additionally, the activity level of patients with LBP was affected by sex, BMI, LBP, and skeletal muscle mass index. These slides can be retrieved under Electronic Supplementary Material.

PURPOSE: We investigated the involvement of sarcopenia in middle-aged and elderly women with degenerative lumbar scoliosis (DLS). METHODS: A total of 971 women (mean age 70.4 years) were included in our study. These included 87 cases of DLS (mean 73.8 years) and 884 controls (69.8). Lumbar and femur BMD was measured for all participants using dual-energy X-ray absorptiometry. We used a bioelectrical impedance analyzer to analyze body composition, including appendicular skeletal muscle mass index (SMI; appendicular lean mass (kg)/(height (m))2. We determined bone density and skeletal muscle mass in both groups and determined the prevalence of sarcopenia. We examined the correlation between bone density and appendicular muscle mass in both groups. We also examined factors related to scoliosis using logistic regression analysis. RESULTS: The DLS group showed significantly higher lumbar BMD, lower femur BMD, lower lean mass arm, and lower lean mass leg, and lower lean mass trunk (p < 0.05). Sarcopenia prevalence (SMI < 5.75) was 59.8% in DLS subjects and 42.8% in controls, revealing a high prevalence in DLS (p < 0.05). In both groups, lumbar and femur BMD were positively correlated with appendicular muscle mass. By logistic regression analysis, trunk muscle mass was detected as a risk factor for DLS independent of age (p < 0.05). CONCLUSIONS: In middle-aged and elderly women, prevalence of sarcopenia was 59.8% in DLS cases and 42.8% in controls, which revealed a high prevalence in DLS. A decrease in trunk muscle was a significant risk factor for DLS that was independent of age. These slides can be retrieved under Electronic Supplementary Material.

Manganese-enhanced magnetic resonance imaging (MEMRI) enables tract tracing to follow neural pathways through axonal transport. However, the method is problematic because of the high local concentrations of Mn2+ involved. We developed a tetrananogel containing a dextran-manganese complex (Dex-Mn-Gel) and applied this nanogel to rats. MnCl2 (n = 5), Dex-Mn-Gel (n = 5), or saline control (n = 3) was injected into the left knee joint of the rats (n = 13). Inflammation and tissue alterations in the knee joint were also evaluated histologically. T1-weighted images were obtained on a 7 T MRI system 24 hours after the administration and compared across groups. The sciatic nerve in both legs and the surrounding musculature were used as regions of interest (ROI). No swelling was found in the knee joint infused with Dex-Mn-Gel, although prominent swelling of the knee joint was observed with MnCl2. White blood cells inside the knee joint tissue infused with the Dex-Mn-Gel were significantly less abundant (45%, P < .05) compared with the knee joints infused with MnCl2. Visualization of the sciatic nerve was significantly enhanced in rats treated with both forms of Mn2+ compared with controls (P < .01). This study is the first to attempt intra-articular administration of a manganese contrast agent into joint-capsule and demonstrate tract visualization. The Dex-Mn-Gel can be taken up by the nerve endings and reduce Mn2+ toxicity. Dex-Mn-Gel will provide a minimally invasive method for visualizing nerve tracts in vivo.

BACKGROUND: Giant cell tumor is known to be a benign neoplasm that arises most commonly in the long bones, while cases in the spine are rare. Recently, denosumab, a monoclonal antibody that inhibits receptor activator of nuclear factor-kappa β ligand, has been used to treat patients with giant cell tumor. However, there are few reports of total en bloc spondylectomy being used for paravertebral giant cell tumor lesions following denosumab therapy. CASE PRESENTATION: Our patient was a 20-year-old Japanese woman with a 4-month history of lower back pain. A spinal computed tomography scan and magnetic resonance imaging of her lumbar spine revealed an osteolytic lesion involving the L3 vertebral body, and the tumor extended toward the left side of the paravertebral soft tissue and into the left pedicle. The lesion was diagnosed as a giant cell tumor by needle biopsy. Denosumab treatment calcified the paravertebral giant cell tumor lesion and the tumor vertebral body was removed completely by total en bloc spondylectomy. CONCLUSION: This case report describes a patient with a paravertebral giant cell tumor who was successfully treated by preoperative denosumab injection followed by total en bloc spondylectomy.

STUDY DESIGN: A basic study using a rodent model of sarcopenia. OBJECTIVE: To elucidate the contribution of oxidative stress to muscle degeneration and the efficacy of antioxidant treatment for sarcopenia using an animal model of neurogenic sarcopenia. SUMMARY OF BACKGROUND DATA: Oxidative stress has been reported to be involved in a number of pathologies, including musculoskeletal disorders. Its relationship with sarcopenia, one of the potential origins of lower back pain, however, is not yet fully understood. METHODS: Myoblast cell lines (C2C12) were treated with H2O2, an oxidative stress inducer, and N-acetyl-L-cysteine (NAC), an antioxidant. Apoptotic effects induced by oxidative stress and the antioxidant effects of NAC were assessed by western blotting, immunocytochemistry, and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) cell viability assays. An animal model of sarcopenia was produced via axotomy of the sciatic nerves to induce muscle atrophy. Twenty-four male Sprague-Dawley rats were divided into sham, sham+NAC, axotomy, and axotomy+NAC groups. Rats were provided water only or water containing NAC (1 g/L) for 4 weeks. The gastrocnemius muscle was isolated and stained with hematoxylin and eosin (H&E) 2 weeks after axotomy, from which muscle cells were harvested and protein extracted for evaluation. RESULTS: Mitogen-activated protein kinases (MAPKs) were significantly activated by H2O2 treatment in C2C12 cells, which was ameliorated by NAC pretreatment. Furthermore, H2O2 induced apoptosis and death of C2C12 cells, which was prevented by NAC pretreatment. The weight of the gastrocnemius muscle was reduced in the axotomy group, which was prevented by NAC administration. Lastly, although muscle specimens from the axotomy group showed greater reductions in muscle fiber, the oral administration of NAC significantly inhibited amyotrophy via antioxidant effects. CONCLUSION: The current in vitro and in vivo study demonstrated the possible involvement of oxidative stress in sarcopenic pathology. NAC represents a potential anti-sarcopenic drug candidate, preventing amyotrophy and fatty degeneration. LEVEL OF EVIDENCE: 4.

STUDY DESIGN: A retrospective observational study was performed. PURPOSE: We investigated the prevalence of sarcopenia in dropped head syndrome (DHS), and the relationship between biochemical markers, including major advanced glycation end products (AGEs), pentosidine, and DHS in older women. OVERVIEW OF LITERATURE: AGEs have been implicated in the pathogenesis of sarcopenia. METHODS: We studied 13 elderly women with idiopathic DHS (mean age, 77.2 years) and 20 healthy volunteers (mean age, 74.8 years). We used a bioelectrical impedance analyzer to analyze body composition, including appendicular skeletal muscle mass index (SMI; appendicular lean mass [kg]/[height (m)]2). Cervical sagittal plane alignment, including C2-C7 sagittal vertical axis (C2-C7SVA), C2-C7 angle, and C2 slope (C2S), was measured. Biochemical markers, such as serum and urinary pentosidine, serum homocysteine, 1, 25-dihydroxyvitamin D, and 25-hydroxyvitamin D, were measured. The level of each variable was compared between DHS and controls. The relationship between biochemical markers and DHS was examined. RESULTS: Sarcopenia (SMI <5.75) was observed at a high prevalence in participants with DHS (77% compared to 22% of healthy controls). Height, weight, femoral bone mineral density, appendicular lean mass, total lean mass, and SMI all had significantly lower values in the DHS group. Serum and urinary pentosidine, and serum homocysteine were significantly higher in the DHS group compared to controls. Analysis of cervical alignment revealed a significant positive correlation of serum pentosidine with C2-C7SVA and C2S. CONCLUSIONS: Sarcopenia was involved in DHS, and high serum pentosidine levels are associated with severity of DHS in older women.

OBJECTIVEThe purpose of this study was to determine the relationship between vertebral bodies, psoas major morphology, and the course of lumbar nerve tracts using diffusion tensor imaging (DTI) before lateral interbody fusion (LIF) to treat spinal deformities.METHODSDTI findings in a group of 12 patients (all women, mean age 74.3 years) with degenerative lumbar scoliosis (DLS) were compared with those obtained in a matched control group of 10 patients (all women, mean age 69.8 years) with low-back pain but without scoliosis. A T2-weighted sagittal view was fused to tractography from L3 to L5 and separated into 6 zones (zone A, zones 1-4, and zone P) comprising equal quarters of the anteroposterior diameters, and anterior and posterior to the vertebral body, to determine the distribution of nerves at various intervertebral levels (L3-4, L4-5, and L5-S1). To determine psoas morphology, the authors examined images for a rising psoas sign at the level of L4-5, and the ratio of the anteroposterior diameter (AP) to the lateral diameter (lat), or AP/lat ratio, was calculated. They assessed the relationship between apical vertebrae, psoas major morphology, and the course of nerve tracts.RESULTSAlthough only 30% of patients in the control group showed a rising psoas sign, it was present in 100% of those in the DLS group. The psoas major was significantly extended on the concave side (AP/lat ratio: 2.1 concave side, 1.2 convex side). In 75% of patients in the DLS group, the apex of the curve was at L2 or higher (upper apex) and the psoas major was extended on the concave side. In the remaining 25%, the apex was at L3 or lower (lower apex) and the psoas major was extended on the convex side. Significant anterior shifts of lumbar nerves compared with controls were noted at each intervertebral level in patients with DLS. Nerves on the extended side of the psoas major were significantly shifted anteriorly. Nerve pathways on the convex side of the scoliotic curve were shifted posteriorly.CONCLUSIONSA significant anterior shift of lumbar nerves was noted at all intervertebral levels in patients with DLS in comparison with findings in controls. On the convex side, the nerves showed a posterior shift. In LIF, a convex approach is relatively safer than an approach from the concave side. Lumbar nerve course tracking with DTI is useful for assessing patients with DLS before LIF.

The incidence of spinal fusion surgery and associated adjacent segment disease (ASD) is steadily increasing. We report three cases of ASD after posterior fixation, treated by oblique lateral interbody fusion (OLIF). All cases had a good postoperative course. Altogether, OLIF surgery may be a viable option for treating ASD.

INTRODUCTION: To investigate the risk of epidural hematoma after spinous process-splitting laminectomy (SPSL). METHODS: A total of 137 cases (mean age, 72.4 years; 68 men) of SPSL were included. Of these, there were instances (3.7%; mean age, 70.5 years; all male) of postoperative development of new neurologic deficit due to epidural hematoma requiring reoperation. The 133 subjects (72.5 years; 64 men) with normal postoperative course were used as controls, and comparisons were made between both groups using chi-squared and Student's t-tests. Regarding our investigation of risk factors for epidural hematoma, logistic regression was conducted with presence or absence of hematoma as our primary outcome variable, and age, gender, disease duration, number of laminectomies, which levels were decompressed, blood loss, length of case, drain output, coagulopathy, and whether or not there was an intraoperative dural tear were our explanatory variables. RESULTS: All cases of hematoma were single-level laminectomies; there was one case of T9-10 and 3 cases of L2-3. In our direct comparison of both groups (hematoma versus control), the proportion of men was significantly higher in the hematoma group (100% versus 48%, p < 0.05); levels decompressed were also significantly higher (p < 0.05) in the hematoma group, and drain outputs were significantly lower (113 mL versus 234 mL, p < 0.05). From our logistic regression analysis, the levels were significantly higher (χ2 = 15, p = 0.0001) and the drain outputs were smaller (χ2 = 4.6, p = 0.03) in the hematoma group. CONCLUSIONS: Single-level decompression higher than the L2-3 level and reduced drain output were risk factors for spinal epidural hematoma. With this method of spinous process suturing and reconstruction there is less decompression compared with more conventional methods; therefore, the effect of hematoma may be more pronounced at higher vertebral levels with reduced canal width, and drain failure may also occur with this limited space.

INTRODUCTION: Limb muscle mass measurement using dual-energy X-ray absorptiometry (DXA) is considered the gold standard for the diagnosis of sarcopenia. Moreover, bioelectrical impedance analysis (BIA) is also recognized as a beneficial tool considering its high correlation with DXA. However, it remains to be elucidated whether DXA and BIA can accurately measure trunk lean mass. The aim of this study was to investigate the correlation between DXA and BIA measurements of trunk muscle mass and the cross-sectional area (CSA) of trunk muscles measured using magnetic resonance imaging (MRI) and to compare measures of trunk muscle mass obtained using DXA and BIA in patients with low back pain (LBP). METHODS: In total, 65 patients participated in the study. The correlation between DXA and BIA measurements and the CSA of trunk and paraspinal muscles at the L4-5 level were calculated. In addition, the correlation between DXA and BIA measurements of trunk muscle mass and the differences between these two measurements were determined. RESULTS: The correlation coefficient between DXA and BIA trunk muscle mass measurement and trunk muscle CSA was 0.74 and 0.56 for men and 0.69 and 0.44 for women, respectively. DXA and BIA measurement values showed a significantly moderate correlation with the CSA of the erector spinae (ES) and psoas major (PM). The multifidus (MF) CSA did not correlate with measurements of DXA and BIA in both men and women. Although DXA and BIA measurements were significantly correlated, a significant difference between these two measurements was found. BIA overestimated the trunk muscle mass significantly compared with DXA. CONCLUSIONS: Trunk muscle mass measured with DXA and BIA was correlated with the CSA of most trunk muscles. Although the measurement of DXA and BIA showed a high correlation, BIA overestimated trunk muscle mass compared with DXA. Both DXA and BIA are beneficial for measuring trunk muscle mass.

INTRODUCTION: Wearable accelerometers can be used to evaluate waking and sleeping movements. Although a correlation between accelerometer data captured at the wrist and waist has been reported, it has not been evaluated in patients with low back pain. Therefore, this study aimed to evaluate correlations between movement measured at the wrist and waist, using wearable accelerometers, in patients with low back pain. METHODS: Twenty patients with chronic low back pain and 20 healthy volunteers were enrolled. Two identical accelerometers were simultaneously worn by each participant, one on the nondominant wrist and the other at the waist, for 1 week. We compared the mean number of active movements and mean total amount of movement between the wrist and the waist to evaluate daytime and sleep activities. During sleep, we also evaluated sleep efficiency and time awake after sleep onset. RESULTS: In daytime activity, the mean number of active movements and mean total amount of movement was greater for the wrist than for the waist, and the amount of waist movements relative to wrist movements was significantly lower in patients with low back pain than in healthy volunteers (p < 0.05). Despite these differences, the mean number of active movements and mean total amount of movement at the wrist and waist were strongly correlated in both groups. During sleep, although there was no difference in either measured sleep efficiency at the wrist or waist or time awake after sleep onset, measurements were strongly correlated in both groups. CONCLUSIONS: A strong correlation between movement data at the wrist and waist during both daytime activities and sleep was identified in patients with low back pain. Therefore, a wearable accelerometer worn on the wrist can reliably measure the movement of patients with low back pain, simplifying data capture for clinical and research purposes and improving patient comfort.

INTRODUCTION: Thus far, few reports have described the time series histological variations in injured paravertebral muscle tissues for long durations, considering the type of pain. The purpose of this study is to evaluate histological changes in injured paravertebral muscles and dominant nerves considering the type of pain. METHODS: We used 59 eight-week-old male Sprague-Dawley rats. A 115-g weight was dropped from a height of 1 m on the right paravertebral muscle. Fluoro-Gold (FG), a sensory nerve tracer, was injected into this muscle. Hematoxylin and eosin (HE) staining and nerve growth factor (NGF) immunostaining of the muscle were performed for histological evaluation. L2 dorsal root ganglia (DRG) on both sides were resected, and immunohistochemical staining was performed for calcitonin gene-related peptide (CGRP, a pain-related neuropeptide) and for activating transcription factor 3 (ATF3, a neuron injury marker). Each examination was performed at 3 days, 1-3 weeks, and 6 weeks after injury. RESULTS: HE staining of the paravertebral muscle indicated infiltration of inflammatory cells and the presence of granulation tissue in the injured part on the ipsilateral side at 3 days and 1 week after the injury. Fibroblasts and adipocytes were present at 2-3 weeks. At 6 weeks, the injured tissue was almost completely repaired. NGF was detected at 2-3 weeks post injury and appeared to colocalize with fibroblasts, but was not observed at 6 weeks post injury. The percentage of cells double-labeled with FG and CGRP in FG-positive cells of the primary muscle was significantly higher in the injured side at 3 days and 1-3 weeks post injury (P < 0.05). However, at 6 weeks, no significant difference was observed. No significant expression of ATF3 was observed. CONCLUSIONS: These results suggest that sensitization of the dominant nerve in the DRG, in which NGF may play an important role, can protract pain in injured muscles.

STUDY DESIGN: A retrospective study. OBJECTIVE: The aim of this study was to determine the publication rate and impact factors (IFs) among all abstracts presented at the 2010 and 2012 meetings of the International Society for the Study of Lumbar Spine (ISSLS). SUMMARY OF BACKGROUND DATA: The publication rate of abstracts presented at overseas meetings was reported to be around 50%. However, the publication rate and IFs of oral and poster presentations made at ISSLS meetings were unclear. Moreover, whether the publication rates and IFs differed for papers associated with oral or poster presentations at ISSLS meetings was unknown. METHODS: We investigated all 1126 abstracts (oral, special posters, general posters) presented at ISSLS meetings held between 2010 and 2012. PubMed was searched to identify publications and IFs were determined using journal citation reports. We also compared the publication rates and IFs between oral and poster presentations. RESULTS: The overall publication rate was 50.1% for three ISSLS meetings (564 publications/1126 abstracts). The overall publication rate for oral presentations, special posters, and general posters given in the 2010 to 2012 meetings was 62.0%, 48.3, and 46.6%, respectively. Overall, papers related to oral presentations had significantly higher publication rates than those of special and general posters (P = 0.0002). The average IFs of publications associated with abstracts presented at three ISSLS meetings was 2.802 for oral presentations, 2.593 for special posters, and 2.589 for general posters. There were no significant differences in average IFs between oral and poster presentations (P > 0.05). CONCLUSION: The publication rate for abstracts presented at ISSLS meetings was high and similar to publication rates for abstracts presented at other meetings concerning orthopedic and spine research. However, there was no significant difference in IFs between oral and poster presentations, suggesting that abstract evaluations cannot predict IFs of the eventual publication. LEVEL OF EVIDENCE: 4.

STUDY DESIGN: Cross-sectional observational study. PURPOSE: To compare measurements of appendicular skeletal muscle mass (ASMM) and whole fat mass (WFM) obtained using dualenergy X-ray absorptiometry (DXA) and bioelectrical impedance analysis (BIA) among patients with low back pain (LBP). Moreover, the study investigated the correlation between BIA-based ASMM and DXA-based bone mineral density (BMD). Overview of the Literature: If reliable, BIA may be a useful alternative to DXA as a screening tool for sarcopenia and osteoporosis among patients with LBP. METHODS: Measurements were performed in 130 patients, including BMD of the lumbar spine and femoral neck. The correlation between DXA and BIA as well as between BIA-ASMM and BMD were evaluated. RESULTS: BIA and DXA were highly correlated in both male and female patients (r =0.73-0.90, p <0.0001). However, BIA consistently overestimated ASMM by 1.5-2.5 kg on an average (p <0.0001) and underestimated WFM (-4.0 to -2.7 kg) on an average (p <0.0001). BIA-based ASMM correlated with BMD of the lumbar spine in both male and female patients (r =0.28-0.37, p ≤0.02) and that of the femoral neck (r =0.34-0.51, p ≤0.005). Regarding the calculated skeletal muscle index (SMI: ASMM/height [m2]) used as a criterion for sarcopenia, BIA-based SMI correlated with BMD of the lumbar spine in male patients (r =0.44, p =0.0004) and that of the femoral neck in female patients (r =0.33, p =0.009). CONCLUSIONS: BIA may be a favorable alternative to DXA as a screening tool for sarcopenia and osteoporosis among patients with LBP. Considering the overestimation of BIA-based ASMM and SMI, we recommend using the cutoff values for sarcopenia of 7.9 kg/m2 for males and 6.1 kg/m2 for females.

type:text [要旨] 【目的】ラット筋損傷モデルを用いて圧迫，冷却療法による治療効果を比較した。 【方法】8 週齢雄性SDラットを用いdrop mass 法にてモデル作成し，損傷後3 時間にゴムで損傷部を30分圧迫した圧迫群（n＝36），氷で損傷部を30分冷却した冷却群（n＝36），未治療群（n＝36）の3 群について比較を行った。損傷後3 ， 6 ，18，24時間， 3 日， 1 週， 2 週の腓腹筋をHE染色で評価した。損傷後3 ，6 ，18，24時間の腓腹筋をELISA法にてTNF-α の定量評価を行った。損傷部にフルオロゴールド(FG）を留置し，損傷後3 日のL4 後根神経節でCGRP（疼痛関連ペプチド）による免疫組織化学染色を行った。 【結果】組織では未治療群と比し，圧迫群は損傷後6 時間以降で出血や浮腫が少ない傾向にあった。冷却群は，損傷後6 時間で出血や浮腫は減少するも，損傷後18時間以降で増強した。損傷後1週で未治療群は筋組織の壊死が残存するも，圧迫群，冷却群は筋線維修復が認められた。サイトカインは，圧迫群は未治療群と比し損傷後3 ， 6 ，18時間共に低値を示した。特に損傷後6 時間で有意に低値であった（P＜0.05）。冷却群は未治療群と比し損傷後3 ，6 時間で一過性な上昇を示すも，損傷後18時間では有意に低下した（P＜0.05）。L4 後根神経節でのFG 陽性細胞中のFG とCGRP で二重標識される細胞の割合は，圧迫群，冷却群ともに未治療群と比し有意に低かった（P＜0.05）。 【考察】圧迫，冷却療法は筋組織修復を促進し，疼痛の遷延化を予防するが，急性期では異なる経時的変化を示し，組織修復過程に差異がある可能性が示唆された。 [SUMMARY] Purpose. To compare compression and ice treatments in a rat model of muscle injury. Methods. A model of muscle injury was made in 108 eight-week-old Sprague Dawley male rats by dropping a weight onto their right gastrocnemius muscle. We compared compression and ice treatments after the contusion injury with no treatment. We evaluated the injuries using histology andan enzyme-linked immunosorbent assay for tumor necrosis factor α. We used Fluoro-Gold to traceneural afferents from the region of the contusion injury. The proportion of calcitonin gene-related peptide-immunoreactive neurons in all Fluoro-Gold-labeled neurons was determined to evaluate pain. Results. In the compression treatment group, the injured muscle tended to have less hemorrhage and edema at ? 6 h after the injury. Tumor necrosis factor α levels were lower, and the local acutephase in flammatory reaction was milder than in untreated rats. We found less necrosis of muscle tissue on the third day after injury and the replacement of granulation tissue and regeneration of muscle fibers 1 week after the injury. The proportion of calcitonin gene-related peptide-immunoreactive Fluoro-Gold-labeled neurons in total Fluoro-Gold-labeled neurons was significantly lower than in untreated rats. In the ice treatment group, although injured muscle had decreased hemorrhage and edema 6 h after the injury, hemorrhage and edema increased ?18 h after injury. Tumor necrosis factor α levels were transiently increased compared with those in untreated rats（ 3 h and 6 h after contusion）. On the third day after contusion injury, necrosis of muscle was severe. We observed the replacement of granulation tissue and regeneration of muscle fibers 1 week after the injury. The proportion of calcitonin gene-related peptide-immunoreactive Fluoro-Gold-labeled neurons was significantly lower than in untreated rats. Conclusion. In our study, compression may promote muscle tissue repair by preventing hematoma formation during the repair phase and preventing prolonged pain. On the other hand, ice therapy may prevent prolonged pain through pain relief from the stimulation of cold receptors, enabling animals to proceed with an early range of motion exercise, suppressing hypoactivity and promoting muscle tissue repair during the recovery phase. Overall, our current study indicated that there was a difference between compression and ice treatments during the acute and repair phases of muscle injury.

OBJECTIVE: To validate the relationship between residual walking ability and monthly care cost as well as long-term care insurance (LTCI) certification level in elderly patients after surgical treatment for hip fractures in Japan. METHODS: Elderly patients aged >75 years who underwent surgical treatment for hip fractures in our hospital were included. The preand post-surgical (6-month) walking ability and LTCI certification and the presence or absence of dementia was determined from medical records and questionnaires. Walking ability was classified into 6 levels used in our daily medical practice. Based on these data, we correlated the relationship between walking ability and the LTCI certification level. Further, based on the official statistics pertaining to the average monthly costs per person at each LTCI certification level, we evaluated the relationship between walking ability and monthly care cost. RESULTS: A total of 105 cases (mean age, 80.2 years; 16 men; 39 patients with dementia) were included. The correlation between walking ability and average monthly cost per person as well as LTCI certification level at 6 months postoperatively (r=0.58) was demonstrated. The correlation was found in both groups with and without dementia. CONCLUSION: The ability to walk reduced the cost of care in elderly patients who experienced hip fracture, regardless of the presence of dementia.

慢性腰痛の病態は多因子からなり、疼痛機序の観点からは全体で約30%の患者に神経障害性疼痛の関与が考えられる。下肢痛や臀部痛のある症例ではその割合は高く、慢性腰痛における特徴の一つと考えられる。また、腰痛患者の活動量の実態をより正確に把握するため行った日常活動度のデータ蓄積と解析によると、特に急性期での睡眠障害の具現化が示唆された。慢性腰痛の病態を検証するうえでは、今後は活動度も含んだより多面的な検証が有用であると考えられる。(著者抄録)