稲毛 一秀

Abstract Diclofenac etalhyaluronate (DF‐HA) sustained diclofenac release with the effects of hyaluronic acid (HA), offering long‐term analgesia in osteoarthritis. In this study, the effects of DF‐HA on pain improvement and osteoarthritis were evaluated in a rat knee monoiodoacetate‐induced osteoarthritis model compared to HA. Eight rats per group had been injected with monoiodoacetate (2.0 mg) or saline in the right knee for 4 weeks and were injected with either DF‐HA (1.25 mg/kg; 0.5 mg), HA (0.5 mg), vehicle which was a substrate without DF‐HA (50 μL), or saline and followed for 4 weeks. Mechanical plantar skin sensitivity was assessed weekly using the von Frey assay. Osteoarthritis changes were monitored with Larsen scores via CT imaging at every 2 weeks. The articular cartilage was analyzed using OARSI scores through H&E, Safranin‐O staining at 8 weeks. The percentage of Iba‐1 positive microglia in the spinal dorsal horn and of FG + CGRP‐labeled cells among FG‐positive cells in the dorsal root ganglion were evaluated by immunohistochemical staining. TNF‐α and IL‐6 mRNA expression levels in the knee synovium were evaluated by PCR. The DF‐HA showed significantly improved pain hypersensitivity compared with the HA at 6–8 weeks. The percentage of Iba‐1‐positive microglia was significantly lower than that in the vehicle and the percentage of FG + CGRP/FG was significantly lower than that in the HA. OARSI scores did not differ among treatment groups, Larsen scores indicated lower in the DF‐HA than in the vehicle. DF‐HA was as effective as HA in joint protection and significantly improved inflammatory pain compared to HA.

Co-administration of mirogabalin besylate and nonsteroidal anti-inflammatory drugs is effective for neuropathic pain; however, mechanism of its action remains unknown. We aimed to evaluate the mechanism of this synergistic effect of the concomitant administration for neuropathic pain using chronic constriction injury model rats. Fifty male Wister rats of 7-week-old were used. Right sciatic nerve ligation was performed in 40 rats and they were sub-divided into four groups: vehicle, mirogabalin, diclofenac sodium and co-administration of them. Ten rats underwent sham surgery. Fluorogold was attached to sciatic nerve during surgery. Von Frey filament and weight bearing tests were performed on postoperative Day 6 as behavioral assessments and drug was administrated intraperitoneally. Half rats in each group underwent behavioral assessment and perfusion fixation using 4% paraformaldehyde on postoperative Day 7 and remaining on postoperative Day 14. Subsequently, dorsal root ganglion at L4 to L6 was collected and examined immunohistochemistry for calcitonin gene-related peptide, and their immunoreactivity in fluorogold-labeled neurons was measured. Spinal cord at lumbar swelling was resected, immunostained for ionized-calcium-binding adapter molecule-1 and glial fibrillary acidic protein, and immunoreactive neurons in dorsal horn of spinal cords were calculated as the occupancy of them. Mirogabalin suppresses the neuropeptide-release from presynaptic afferent neuron directly and it resulted in suppressing glia cells activation. Diclofenac sodium inhibits cyclooxygenase-2 and prostaglandin production, related to allodynia. These effects of mirogabalin and diclofenac sodium, respectively, inhibited glia cells strongly, which is presumed to be one of the mechanisms for the effectiveness of their co-administration for neuropathic pain.

BACKGROUND: This study aimed to validate alterations in the gene expression of DNA methylation-related enzymes and global methylation in the peripheral blood mononuclear cell (PBMC) and synovial tissues of animal hip osteoarthritis (OA) models. METHODS: Animals were assigned to the control (no treatment), sham (25 µL of sterile saline), and OA (25 µL of sterile saline and 2 mg of monoiodoacetate) groups. Microcomputed tomography scan, histopathological assessment and pain threshold measurement were performed after induction. The mRNA expression of the DNA methylation machinery genes and global DNA methylation in the PBMC and hip synovial tissue were evaluated. RESULTS: The OA group presented with hip joint OA histopathologically and radiologically and decreased pain threshold. The mRNA expression of DNA methyltransferase (Dnmt 3a), ten-eleven translocation (Tet) 1 and Tet 3 in the synovial tissue of the OA group was significantly upregulated. Global DNA methylation in the synovial tissue of the OA group was significantly higher than that of the control and sham groups. CONCLUSIONS: The intra-articular administration of monoiodoacetate induced hip joint OA and decreased pain threshold. The DNA methylation machinery in the synovial tissues of hip OA was altered.

INTRODUCTION: Platelet-rich plasma obtained by centrifuging peripheral blood can promote osteogenesis owing to its abundant growth factors but has drawbacks, including rapid growth factor loss and inconsistent effects depending on donor factors. To overcome these issues, we were the first in the world to use freeze-dried human induced pluripotent stem cell-derived megakaryocytes and platelets (S-FD-iMPs) and found that they have osteogenesis-promoting effects. Since turbulence was found to activate platelet biogenesis and iPS cell-derived platelets can now be produced on a clinical scale by a device called VerMES, this study examined the osteogenesis-promoting effect and safety of clinical-scale FD-iMP (V-FD-iMPs) for future human clinical application. METHOD: We administered either S-FD-iMPs, V-FD-iMPs, or saline along with artificial bone to the lumbar spine of 8-week-old male Sprague-Dawley rats (n = 4 each) and evaluated bone formation by computed tomography (CT) and pathology. Next, we administered V-FD-iMPs or saline along with artificial bone to the lumber spines of 5-week-old male New Zealand White rabbits (n = 4 each) and evaluated the bone formation by CT and pathology. Rats (n = 10) and rabbits (n = 6) that received artificial bone and V-FD-iMPs in the lumbar spine were also observed for 6 months for adverse events, including infection, tumor formation, and death. RESULTS: Both V-FD-iMPs and S-FD-iMPs significantly enhanced osteogenesis in the lumber spines of rats in comparison with the controls 8 weeks postoperatively, with no significant differences between them. Furthermore, V-FD-iMPs vigorously promoted osteogenesis in the lumber spines of rabbits 8 weeks postoperatively. In rats and rabbits, V-FD-iMPs showed no adverse effects, including infection, tumor formation, and death, over 6 months. CONCLUSION: These results suggest that V-FD-iMPs promote safe osteogenesis.

PURPOSE: MIXTURE is a simultaneous morphological and quantitative imaging sequence developed by Philips that provides high-resolution T2 maps from the imaged series. We aimed to compare the T2 maps of MIXTURE and SHINKEI-Quant (S-Q) in the cervical spine and to examine their usefulness in the functional diagnosis of cervical radiculopathy. METHODS: Seven healthy male volunteers (mean age: 31 ± 8.0 years) and one patient with cervical disc herniation (44 years old, male) underwent cervical spine magnetic resonance imaging (MRI), and T2-mapping of each was performed simultaneously using MIXTURE and S-Q in consecutive sequences in one imaging session. The standard deviation (SD) of the T2 relaxation times and T2 relaxation times of the bilateral C6 and C7 dorsal root ganglia (DRG) and C5/6 level cervical cord on the same slice in the 3D T2-map of the cervical spine coronal section were measured and compared between MIXTURE and S-Q. RESULTS: T2 relaxation times were significantly shorter in MIXTURE than in S-Q for all C6, C7 DRG, and C5/6 spinal cord measurements. The SD values of the T2 relaxation times were significantly lower for MIXTURE in the C5/6 spinal cord and C7 DRG. In cervical disc herniation, MRI showed multiple intervertebral compression lesions with spinal canal stenosis at C5/6 and disc herniation at C6/7. CONCLUSION: MIXTURE is useful for preoperative functional diagnosis. T2-mapping using MIXTURE can quantify cervical nerve roots more accurately than the S-Q method and is expected to be clinically applicable to cervical radiculopathy.

OBJECTIVE: The goal of this study was to evaluate, using computed tomography (CT) and magnetic resonance imaging (MRI), patients who underwent oblique lateral interbody fusion (OLIF) using either expandable or static interbody spacers. METHODS: Thirty-five patients with degenerative disc disease were surgically treated with one-level OLIF and were followed up for more than 6 months. The Static group consisted of 22 patients, and 13 patients were in the Expandable group. Intraoperative findings included operative time (min), blood loss (ml), and cage size. Low back pain, leg pain, and leg numbness were measured using the Japanese Orthopedic Association score, visual analogue score, and the Roland-Morris Disability Questionnaire. Radiologic evaluation using computed tomography (CT) and magnetic resonance imaging (MRI) allowed measurement of cage subsidence, cross-sectional area (CSA) of the dural sac, disc height, segmental lordosis, foraminal height, and foraminal CSA preoperatively and 6 months postoperatively. RESULTS: The Expandable group had significantly larger cage height and lordosis than the Static group (P < 0.05). The Expandable group also had greater dural sac area expansion and enlargement of the intervertebral foramen, as well as better correction of vertebral body slip (P < 0.05). Cage subsidence was significantly lower in the Expandable group (P < 0.05). JOA and VAS scores for leg numbness were significantly better in the Expandable group (P < 0.05). CONCLUSIONS: Compared with static spacers, expandable spacers significantly enlarged the dural sac area, corrected vertebral body slippage, expanded the intervertebral foramen, and achieved good indirect decompression while reducing cage subsidence, resulting in improvement in clinical symptoms.

PURPOSE: To investigate longitudinal changes in bone mineral density (BMD) in middle-aged female patients who underwent spinal fusion for adolescent idiopathic scoliosis (AIS). METHODS: The study subjects were 229 female patients who were diagnosed with AIS and underwent spinal fusion between 1968 and 1988. A two-step survey study was conducted on 19 female AIS patients. BMD, Z-scores, T-scores, and the prevalence of osteoporosis and osteopenia were compared between the initial (2014-2016) and second (2022) surveys. Correlations between the annual changes in Z-scores and T-scores with radiographic parameters, body mass index (BMI), and the number of remaining mobile discs were analyzed. RESULTS: BMD decreased significantly from the initial (0.802 ± 0.120 g/cm2) to the second survey (0.631 ± 0.101 g/cm2; p < 0.001). Z-scores decreased from 0.12 ± 1.09 to - 0.14 ± 1.04, while T-scores decreased significantly from - 0.70 ± 1.07 to - 1.77 ± 1.11 (p < 0.001). The prevalence of osteopenia and osteoporosis increased significantly from 36.8% to 89.5% (p = 0.002), but the increase in osteoporosis alone was not statistically significant (5.3% to 26.3%; p = 0.180). Moderate negative correlations were found between annual changes in Z-scores and both main thoracic (MT) curve (r = - 0.539; p = 0.017) and lumbar curve (r = - 0.410; p = 0.081). The annual change in T-scores showed a moderate negative correlation with the MT curve (r = - 0.411; p = 0.081). CONCLUSION: Significant reductions in BMD and an increased prevalence of osteopenia and osteoporosis were observed in middle-aged female AIS patients who had undergone spinal fusion. The decline in Z-scores in patients with AIS suggested that there was an accelerated loss of BMD compared with the general population. Larger residual curves could pose an added osteoporosis risk. Further research is needed to understand if the onset of osteoporosis in AIS patients is attributable to the condition itself or the surgical intervention.

INTRODUCTION: Low-back pain causes sleep disorders, which impairs the quality of life (QOL) of patients. Sleep disorders are associated with lumbar spinal stenosis (LSS); however, the postoperative effects of LSS surgery on sleep disorders are unknown. This study aimed to assess sleep disorders in patients with LSS using wearable activity trackers and determine whether surgery improves sleep quality. METHODS: A total of 39 patients scheduled for LSS surgery (mean age 71.1±8.7 years; 22 men and 17 women) were studied. Sleep disorders in the participants were objectively evaluated using a wearable Motionlogger Micro system. Sleep efficiency (SEf), mean active count (MAC), and wake after sleep onset (WASO) were measured before and 6 months following surgery. Furthermore, the patient-based outcomes of pain and QOL-related scores were measured and compared with those of healthy participants. The group with improved SEf following surgery was designated as "nonpoor sleepers," whereas the group that did not exhibit improvements was designated as "poor sleepers." The two groups were compared based on patient factors, patient-based questionnaires, and sleep disorder measurements. RESULTS: The SEf and WASO were significantly worse in patients with LSS compared with healthy participants (P<0.05). Furthermore, the SEf in patients with LSS was associated with the Oswestry Disability Index scores. No improvement was observed in the SEf, MAC, and WASO before and after surgery. Evaluation of each case revealed 21 and 12 cases of nonpoor and poor sleepers, respectively. Preoperative low-back pain was significantly associated with improvement in postoperative sleep quality. CONCLUSIONS: Sleep disorders in patients with LSS were evaluated, and improvement in sleep disorders following surgery was associated with the intensity of preoperative low-back pain. Sleep disorders are associated with QOL disorders, suggesting that focusing on the treatment of sleep disorders is important in the management of patients with LSS.

Platelet-rich plasma (PRP) promotes bone union through osteoinduction. We investigated whether adding demineralized bone matrix (DBM), derived naturally from biomaterial and with various growth factors, for osteoconductivity and bone marrow fluid for osteogenesis results in different bone unions. Eight-week-old male Sprague-Dawley rats were divided into four groups of five based on transplantation material: sham control (C group); DBM alone (D group); DBM + PRP (DP group); and DBM + PRP + bone marrow fluid (DPB group). After posterolateral fusion at L3-5, postoperative weekly CT imaging determined average number of bone union in facet joints (4 joints × 5 animals = 20 joints) and bone formation. Pathological evaluation and bone strength were assessed using 3-point bending two weeks postoperatively. Facet joint bone union at four weeks postoperatively was 4/20 (20%, DP group) and 8/20 (40%, DPB group) joints. Six weeks postoperatively, it was 7/20 (35%, D group), 12/20 (60%, DP group), and 16/20 (80%, DPB group). Eight weeks postoperatively, it was 13/20 (65%, D group), 17/20 (85%, DP group), and 20/20 (100%, DPB group), suggesting that DPB > DP > D > C. Bone formation and bone strength showed a similar DPB > DP > D > C group trend. Adding PRP and bone marrow fluid to DBM promotes bone union and strength.

STUDY DESIGN: Retrospective study. PURPOSE: To compare the radiographic risk factors for decreased cervical lordosis (CL) after laminoplasty, focusing on the difference between cervical spondylotic myelopathy (CSM) and cervical ossification of the posterior longitudinal ligament (C-OPLL). OVERVIEW OF LITERATURE: A few reports compared the risk factors for decreased CL between CSM and C-OPLL although these two pathologies have their characteristics. METHODS: This study included 50 patients with CSM and 39 with C-OPLL who underwent multi-segment laminoplasty. Decreased CL was defined as the difference between preoperative and 2-year postoperative neutral C2-7 Cobb angles. Radiographic parameters included preoperative neutral C2-7 Cobb angles, C2-7 sagittal vertical axis (SVA), T1 slope (T1S), dynamic extension reserve (DER), and range of motion. The radiographic risk factors were investigated for decreased CL in CSM and C-OPLL. Additionally, the Japanese Orthopedic Association (JOA) score was assessed preoperatively and 2 years postoperatively. RESULTS: C2-7 SVA (p =0.018) and DER (p =0.002) were significantly correlated with decreased CL in CSM, while C2-7 Cobb angle (p =0.012) and C2-7 SVA (p =0.028) were correlated with decreased CL in C-OPLL. Multiple linear regression analysis revealed that greater C2-7 SVA (B =0.22, p =0.026) and small DER (B =-0.53, p =0.002) were significantly associated with decreased CL in CSM. By contrast, greater C2-7 SVA (B =0.36, p =0.031) was significantly associated with decreased CL in C-OPLL. The JOA score significantly improved in both CSM and C-OPLL (p <0.001). CONCLUSIONS: C2-7 SVA was associated with a postoperative decreased CL in both CSM and C-OPLL, but DER was only associated with decreased CL in CSM. Risk factors for decreased CL slightly differed depending on the etiology of the condition.

Background In recent years, advances in the treatment of malignant tumors have improved life expectancy and diversified treatment options. However, maintaining high activities of daily living in patients is essential for appropriately treating the primary disease, and interventions for patients with impaired motor function will lead to improved quality of life. Here, we compared the muscle mass of malignant tumor patients who are visiting bone metastasis outpatient clinics with that of healthy subjects. Methods We compared the muscle mass of 61 malignant tumor patients with an Eastern Cooperative Oncology Group (ECOG) performance status ≤ 2 (mean 66.3 ± 12.0 years; 30 males and 31 females) attending our bone metastasis outpatient clinic since 2018 with that of 315 healthy subjects (mean 65.0 ± 17.7 years; 110 males and 205 females). Body mass index, skeletal muscle mass, and body fat percentage were assessed by bioimpedance analysis, and the skeletal muscle mass index (SMI) was calculated. Results To eliminate age bias in the malignant tumor patients and healthy subjects, 1:1 propensity score matching was performed separately for males and females. There was no significant difference in right upper limb, left upper limb, right lower limb, or left lower limb mass or SMI between the two groups, whereas trunk muscle mass and muscle mass were significantly higher in the healthy females compared with malignant tumor females. Conclusion There was no significant difference in the SMI measured by bioimpedance analysis between the two groups in either males or females, while muscle mass and trunk muscle mass were significantly lower in female malignant tumor patients than in healthy subjects. These results suggest that even malignant tumor patients whose performance status was maintained enough to allow outpatient visits still had impaired motor function.

Sarcopenia is defined as decreasing in muscle strength and mass, and dynapenia is defined as decreasing in muscle strength and maintained muscle mass. This study elucidated the prevalence and characteristics of sarcopenia and dynapenia and evaluate in elderly spinal disorders patients. 1039 spinal disorders patients aged ≥ 65 years were included. We measured age, grip strength, muscle mass, spinal sagittal alignment parameters, low back pain (LBP) scores and health-related quality of life (HR-QoL) scores. Based on the previous reports, patients were categorised into normal group: NG, pre-sarcopenia group: PG, dynapenia group: DG, and sarcopenia group: SG. Pre-sarcopenia, dynapenia, and sarcopenia were found in 101 (9.7%), 249 (19.2%), and 91 (8.8%) patients, respectively. The spinal sagittal alignment parameters, trunk muscle mass, LBP, and HR-QoL scores were significantly worse in DG and SG compared with those in PG and NG. Spinal alignment, trunk muscle mass, and clinical outcomes, including LBP and HR-QoL scores, were maintained in the PG and poor in the DG and SG. Thus, intervention for muscle strength may be a treatment option for changes of spinal sagittal alignment and low back pain.

OBJECTIVE: This study aimed to examine whether preoperative severity and location of lumbar intervertebral disc vacuum phenomenon (VP) influence surgical outcomes after single-level transforaminal lumbar interbody fusion. METHODS: We included 106 patients (age, 67.4 ± 10.4 years; 51 male/55 female) with lumbar degenerative diseases, who were treated with single-level transforaminal lumbar interbody fusion. Severity of VP (SVP) score was measured preoperatively. SVP score at fused disc was used as SVP (FS) score and at nonfused discs was used as SVP (non-FS) score. Surgical outcomes were assessed using the Oswestry Disability Index (ODI) and visual analog scale (VAS; low back pain (LBP), lower extremity pain, numbness, LBP in motion, in standing, and in sitting). The patients were divided into severe VP (FS or non-FS) and mild VP (FS or non-FS) groups, and surgical outcomes were compared between the 2 groups. Correlations between each SVP score and surgical outcomes were analyzed. RESULTS: There were no differences in surgical outcomes between the severe VP (FS) and mild VP (FS) groups. Postoperative ODI, VAS score for LBP, lower extremity pain, numbness, and LBP in standing were significantly worse in the severe VP (non-FS) group than in the mild VP (non-FS) group. SVP (non-FS) scores significantly correlated with postoperative ODI, VAS score for LBP, lower extremity pain, numbness, and LBP in standing; however, SVP (FS) scores did not correlate with any surgical outcomes. CONCLUSIONS: Preoperative SVP at fused disc is not associated with surgical outcomes; however, SVP at nonfused discs is correlated with clinical outcomes.

STUDY DESIGN: Retrospective study. OBJECTIVE: The aim was to clarify the health-related quality of life (QOL) of patients who had adolescent idiopathic scoliosis (AIS) at a minimum of 40 years after surgery. SUMMARY OF BACKGROUND DATA: The postoperative health-related QOL of middle-aged patients with AIS has been reported to be good, but that of middle-aged and older patients with AIS has yet to be completely explored. MATERIALS AND METHODS: We included 179 patients with AIS who underwent spinal fusion(s) between 1968 and 1982. We conducted three surveys in 2009, 2014, and 2022. Patients self-administered both the Scoliosis Research Society-22 and the Roland-Morris Disability questionnaires three times (in 2009, 2014, and 2022) and the Oswestry Disability Index (ODI) questionnaire was self-administered in 2014 and 2022. We considered patients who responded to all three surveys in 2009, 2014, and 2022. RESULTS: For the Scoliosis Research Society-22 questionnaires, no significant differences were detected among the three time points (2009, 2014, and 2022) for total scores, function domain, pain domain, self-image domain, mental domain, or satisfaction domain. The results of the Roland-Morris Disability Questionnaire were also not significantly different among the surveys over time. The ODI questionnaires revealed a significant worsening of the 2022 results compared with the 2014 results. Eight patients (29.6%) who had an ODI deterioration of 10% or more had numerically fewer mobile lumbar disks than those with <10% deterioration of the ODI, although the difference did not reach statistical significance. CONCLUSION: Among patients with AIS who underwent spinal fusion(s) between 1968 and 1982, we found health-related QOL to be maintained over the last 13 years. Relatively good QOL was appreciated in this population of patients who are now middle-aged and older.

STUDY DESIGN: A retrospective analysis of magnetic resonance imaging (MRI). OBJECTIVE: The study aimed to evaluate the performance of a convolutional neural network (CNN) to differentiate spinal pyogenic spondylitis from Modic change on MRI. We compared the performance of CNN to that of four clinicians. SUMMARY OF BACKGROUND DATA: Discrimination between pyogenic spondylitis and spinal Modic change is crucial in clinical practice. CNN deep-learning approaches for medical imaging are being increasingly utilized. METHODS: We retrospectively reviewed MRIs from pyogenic spondylitis and spinal Modic change patients. There were 50 patients per group. Sagittal T1-weighted (T1WI), sagittal T2-weighted (T2WI), and short TI inversion recovery (STIR) MRIs were used for CNN training and validation. The deep learning framework Tensorflow was used to construct the CNN architecture. To evaluate CNN performance, we plotted the receiver operating characteristic curve and calculated the area under the curve. We compared the accuracy, sensitivity, and specificity of CNN diagnosis to that of a radiologist, spine surgeon, and two orthopedic surgeons. RESULTS: The CNN-based area under the curves of the receiver operating characteristic curve from the T1WI, T2WI, and STIR were 0.95, 0.94, and 0.95, respectively. The accuracy of the CNN was significantly greater than that of the four clinicians on T1WI and STIR (P<0.05), and better than a radiologist and one orthopedic surgeon on the T2WI (P<0.05). The sensitivity was significantly better than that of the four clincians on T1WI and STIR (P<0.05), and better than a radiologist and one orthopedic surgeon on the T2WI (P<0.05). The specificity was significantly better than one orthopedic surgeon on T1WI and T2WI (P<0.05) and better than both orthopedic surgeons on STIR (P<0.05). CONCLUSION: We differentiated between Modic changes and pyogenic spondylitis using a CNN that interprets MRI. The performance of the CNN was comparable to, or better than, that of the four clinicians.

INTRODUCTION: Preoperative difference in lumbar lordosis (DiLL) was associated with surgical outcomes after single-level transforaminal lumbar interbody fusion (TLIF). Patients with DiLL>0 (DiLL (+)) tended to show worse clinical outcomes and postoperative greater restoration of lumbar lordosis (LL). However, some patients with DiLL (+) showed relatively good outcomes and no postoperative LL restration. This study aimed to elucidate whether the lumbar intervertebral disc vacuum phenomenon (VP) influences clinical course after single-level TLIF in patients with DiLL (+) and DiLL (-). METHODS: Patients with lumbar spinal stenosis and degenerative spondylolisthesis treated with single-level TLIF were included. Pre- and postoperative LL were measured, and postoperative LL improvement was calculated. Preoperative DiLL was calculated as preoperative supine LL minus standing LL. Severity of VP at the non-fused discs (SVP (non-FS)) was evaluated using preoperative reconstructed computed tomography imaging. Clinical outcomes were assessed using the Oswestry disability index, visual analogue scale (VAS; low back pain (LBP), lower-extremity pain, numbness, and the Japanese Orthopaedic Association Back Pain Evaluation Questionnaire. Patients were stratified by the median preoperative SVP (non-FS) score into severe and mild VP groups in patients with DiLL (+) or DiLL (-), and their surgical outcomes were compared. RESULTS: Overall, 89 patients were included. In patients with DiLL (+) (n = 37), patients with severe VP showed worse clinical outcomes, particulary for LBP and DiLL (+) patients with mild VP showed greater LL improvement (6.5° ± 10.0°). In patients with DiLL(-) (n = 52), patients with severe VP showed worse clinical outcomes, particularly for LBP and no differences in preoperative, postoperative, and improvement of LL were observed between two groups. CONCLUSION: Patients with DiLL (+) and DiLL (-) showed different clinical courses depending on VP severity at the non-fused discs after single-level TLIF.

OBEJECTIVE: To perform a magnetic resonance imaging T2-mapping of the ligamentum flavum in healthy individuals and patients with lumbar spinal stenosis scheduled for surgery and compare the T2 relaxation times. SUBJECTS AND METHODS: The T2 relaxation time of the ligamentum flavum was compared among 3 groups, healthy young individuals (H group (age< 50)), healthy middle-aged and older individuals (H group (age≥50)), and patients with lumbar spinal stenosis (L group). Additionally, the thickness of the ligament was measured in the axial image plane, and the occupied area ratio of each fiber was measured by staining the surgically obtained ligament, and each was correlated with the T2 relaxation time. We also evaluated the adhesion of the ligamentum flavum with the dura mater during the surgery. RESULTS: The T2 relaxation times were significantly prolonged in H group (age ≥50) and L group (P < 0.001) compared to H group (age<50). The relationship between collagen fiber and T2 relaxation times was significantly positive (r = 0.720, P < 0.001). Moreover, the relaxation times were significantly prolonged in those with adhesion of the ligamentum flavum with the dura mater (P < 0.05). The cut-off for the relaxation time was 50 ms (sensitivity: 62.50%, false positive rate: 10.8%). CONCLUSION: Healthy middle-aged and older individuals and patients with lumbar spinal stenosis and adhesion of the ligamentum flavum with the dura mater have prolonged T2 relaxation times. Hence, the adhesion between the ligamentum flavum and dura mater should be considered in cases with a relaxation time ≥50 ms.

PURPOSE: Spinal cord segmentation is the first step in atlas-based spinal cord image analysis, but segmentation of compressed spinal cords from patients with degenerative cervical myelopathy is challenging. We applied convolutional neural network models to segment the spinal cord from T2-weighted axial magnetic resonance images of DCM patients. Furthermore, we assessed the correlation between the cross-sectional area segmented by this network and the neurological symptoms of the patients. METHODS: The CNN architecture was built using U-Net and DeepLabv3 + and PyTorch. The CNN was trained on 2762 axial slices from 174 patients, and an additional 517 axial slices from 33 patients were held out for validation and 777 axial slices from 46 patients for testing. The performance of the CNN was evaluated on a test dataset with Dice coefficients as the outcome measure. The ratio of CSA at the maximum compression level to CSA at the C2 level, as segmented by the CNN, was calculated. The correlation between the spinal cord CSA ratio and the Japanese Orthopaedic Association score in DCM patients from the test dataset was investigated using Spearman's rank correlation coefficient. RESULTS: The best Dice coefficient was achieved when U-Net was used as the architecture and EfficientNet-b7 as the model for transfer learning. Spearman's rs between the spinal cord CSA ratio and the JOA score of DCM patients was 0.38 (p = 0.007), showing a weak correlation. CONCLUSION: Using deep learning with magnetic resonance images of deformed spinal cords as training data, we were able to segment compressed spinal cords of DCM patients with a high concordance with expert manual segmentation. In addition, the spinal cord CSA ratio was weakly, but significantly, correlated with neurological symptoms. Our study demonstrated the first steps needed to implement automated atlas-based analysis of DCM patients.

PURPOSE: Thoracolumbar spine injury is frequently seen with high-energy trauma but dislocation fractures are relatively rare in spinal trauma, which is often neurologically severe and requires urgent treatment. Therefore, it is essential to understand other concomitant injuries when treating dislocation fractures. The purpose of this study is to determine the differences in clinical features between thoracolumbar spine injury without dislocation and thoracolumbar dislocation fracture. METHODS: We conducted an observational study using the Japan Trauma Data Bank (2004-2019). A total of 734 dislocation fractures (Type C) and 32,382 thoracolumbar spine injuries without dislocation (Non-type C) were included in the study. The patient background, injury mechanism, and major complications in both groups were compared. In addition, multivariate analysis of predictors of the diagnosis of dislocation fracture using logistic regression analysis were performed. RESULTS: Items significantly more frequent in Type C than in Non-type C were males, hypotension, bradycardia, percentage of complete paralysis, falling objects, pincer pressure, accidents during sports, and thoracic artery injury (P < 0.001); items significantly more frequent in Non-type C than in Type C were falls and traffic accidents, head injury, and pelvic trauma (P < 0.001). Logistic regression analysis showed that younger age, male, complete paralysis, bradycardia, and hypotension were associated with dislocation fracture. CONCLUSION: Five associated factors were identified in the development of thoracolumbar dislocation fractures. LEVEL OF EVIDENCE: III.

BACKGROUND: Diclofenac etalhyaluronate (DF-HA) is a recently developed analgesic conjugate of diclofenac and hyaluronic acid that has analgesic and anti-inflammatory effects on acute arthritis. In this study, we investigated its analgesic effect on osteoarthritis, using a rat model of monoiodoacetate (MIA). METHODS: We injected MIA into the right knees of eight 6-weeks-old male Sprague-Dawley rats. Four weeks later, rats were randomly injected with DF-HA or vehicle into the right knee. Seven weeks after the MIA injection, fluorogold (FG) and sterile saline were injected into the right knees of all the rats. We assessed hyperalgesia with weekly von Frey tests for 8 weeks after MIA administration. We took the right knee computed tomography (CT) as radiographical evaluation every 2 weeks. All rats were sacrificed 8 weeks after administration of MIA for histological evaluation of the right knee and immunohistochemical evaluation of the DRG and spinal cord. We also evaluated the number of FG-labeled calcitonin gene-related peptide (CGRP)-immunoreactive(ir) neurons in the dorsal root ganglion (DRG) and ionized calcium-binding adapter molecule 1 (Iba1)-ir microglia in the spinal cord. RESULTS: Administration of DF-HA significantly improved pain sensitivity and reduced CGRP and Iba1 expression in the DRG and spinal cord, respectively. However, computed tomography and histological evaluation of the right knee showed similar levels of joint deformity, despite DF-HA administration. CONCLUSION: DF-HA exerted analgesic effects on osteoarthritic pain, but did not affect joint deformity.

INTRODUCTION: Post-operative urinary retention is a common complication of posterior spine surgery for lumbar spinal stenosis. However, it can result in considerable difficulty for the patient, especially when it is severe, as in cases of complete retention. Therefore, it is crucial to consider its risk factors. This report provides a retrospective review of cases with severe post-operative urinary retention with the aim of elucidating its possible risk factors. CASE PRESENTATION: Data of five patients with post-operative urinary retention after posterior spine surgery for lumbar spinal stenosis, operated in our facility from 2013 to 2020, were analyzed. Their age, preoperative Japanese Orthopaedic Association (JOA) score, presence of pre-operative bladder and bowel disorders (BBD), presence of pre-operative muscle weakness, the mean number of vertebral levels operated on, complications such as intraoperative dural tear and hematoma, operative time, estimated blood loss, JOA score in the early post-operative period, and the recovery period for the urinary retention symptoms were examined. The mean pre-operative JOA score was 8.4, and the mean number of operated levels was 2.8. The incidence of pre-operative BBD, pre-operative muscle weakness, intraoperative dural tears, and post-operative hematoma was two each. The mean operative time was 242 min, mean estimated blood loss was 352 g, and the mean JOA score in the early post-operative period was 5.8. The recovery period for urinary retention ranged from 4 days to 9 months postoperatively; one patient also had cervical and thoracic spinal stenosis and underwent decompression of all stenotic levels for relief from complete urinary retention. CONCLUSION: In our retrospective review of cases with severe post-operative urinary retention after lumbar spinal stenosis surgery, all patients had severe pre-operative symptoms and spinal stenosis at multiple levels. An awareness of potential risk factors and carefully and gently performing the intraoperative procedures can facilitate lesser damage to the spinal nerve.

The emergency department is an environment with a potential risk for diagnostic errors during trauma care, particularly for fractures. Convolutional neural network (CNN) deep learning methods are now widely used in medicine because they improve diagnostic accuracy, decrease misinterpretation, and improve efficiency. In this study, we investigated whether automatic localization and classification using CNN could be applied to pelvic, rib, and spine fractures. We also examined whether this fracture detection algorithm could help physicians in fracture diagnosis. A total of 7664 whole-body CT axial slices (chest, abdomen, pelvis) from 200 patients were used. Sensitivity, precision, and F1-score were calculated to evaluate the performance of the CNN model. For the grouped mean values for pelvic, spine, or rib fractures, the sensitivity was 0.786, precision was 0.648, and F1-score was 0.711. Moreover, with CNN model assistance, surgeons showed improved sensitivity for detecting fractures and the time of reading and interpreting CT scans was reduced, especially for less experienced orthopedic surgeons. Application of the CNN model may lead to reductions in missed fractures from whole-body CT images and to faster workflows and improved patient care through efficient diagnosis in polytrauma patients.

Abstract The lifetime prevalence of low back pain is 83%. Since there is a lack of evidence for therapeutic effect by cognitive behavioral therapy (CBT) or physical therapy (PT), it is necessary to develop objective physiological indexes and effective treatments. We conducted a prospective longitudinal study to evaluate the treatment effects of CBT, PT, and neurofeedback training (NFT) during alpha wave NFT. The early-chronic cases within 1 year and late-chronic cases over 1 year after the diagnosis of chronic low back pain were classified into six groups: Controls, CBTs, PTs, NFTs, CBT-NFTs, PT-NFTs. We evaluated the difference in EEG, psychosocial factors, scores of low back pain before/after the intervention. Therapeutic effect was clearly more effective in the early-chronic cases. We found that the intensity of alpha waves increased significantly after therapeutic intervention in the NFT groups, but did not have the main effect of reducing low back pain; the interaction between CBT and NFT reduced low back pain. Factors that enhance therapeutic effect are early intervention, increased alpha waves, and self-efficacy due to parallel implementation of CBT/PT and NFT. A treatment protocol in which alpha wave neurofeedback training is subsidiarily used with CBT or PT should be developed in the future.

Although most patients who undergo transforaminal lumbar interbody fusion (TLIF) show favorable surgical results, some still have unfavorable results for various reasons. This study aimed to investigate the influence of differences in lumbar lordosis (LL) between the standing and supine positions (DiLL: supine LL-standing LL) on minimum 5-year surgical outcomes after short-segment TLIF. Ninety-one patients with lumbar degenerative disease who underwent short-segment TLIF (1-2 levels) were categorized based on preoperative differences in LL as DiLL (+) and DiLL (-). Comparison and correlation analyses were performed. The incidence of adjacent segment disease (ASD) by radiology (R-ASD) and symptomatic ASD (S-ASD), bony fusion rates, and pre- and postoperative clinical scores (visual analog scale [VAS]; Japanese Orthopaedic Association [JOA] score; Oswestry disability index (ODI); and Nakai's score) were evaluated. Postoperatively, VAS for low back pain (LBP) in the sitting position, JOA scores for LBP, lower leg pain, intermittent claudication, ODI, and Nakai's score were significantly worse in the DiLL (+) group than in the DiLL (-) group. DiLL values were significantly correlated with VAS for LBP, ODI, and Nakai's score, postoperatively. Positive DiLL values were associated with poorer postoperative outcomes. DiLL is a simple and useful method for predicting mid-term outcomes after TLIF.

We investigated the analgesic effects of tramadol and the arthritic changes following tramadol administration in the rat hip osteoarthritis (OA) model using mono-iodoacetate (MIA). The right hip joints of male Sprague-Dawley rats (n = 5 rats/group) in the Sham group were injected with 25 μl of sterile saline and 1% of fluorogold (FG) retrograde neurotracer. In the MIA + Vehicle and MIA + Tramadol groups, FG and 25 μl of sterile saline with 0.5 mg of MIA were injected into the right hip joint. The MIA + Vehicle and MIA + Tramadol groups were administered daily for 4 weeks, either sterile saline (10 mg/kg, intraperitoneal [i.p.]) or tramadol (10 mg/kg, i.p.). We assessed hyperalgesia every week after MIA administration. Histopathological changes and immunoreactive neurons for calcitonin gene-related peptide (CGRP) in dorsal root ganglia (DRG) were evaluated after 4 weeks of treatment. MIA injection into the hip joint led to mechanical hyperalgesia (p < 0.01), which was significantly reduced by tramadol administration (p < 0.01). Furthermore, daily i.p injection of tramadol significantly suppressed CGRP expression in DRG (p < 0.0001). MIA + Vehicle and MIA + Tramadol groups showed significant cartilage reduction and degeneration compared to the Sham group (p < 0.0001). Interestingly, OA changes significantly progressed in the MIA + Tramadol group compared to the MIA + Vehicle group (p < 0.0001).

INTRODUCTION: We report two cases that required revision surgery with thoracotomy for massive hematoma after anterior kyphorectomy surgery. CASE REPORT: A woman with significant thoracolumbar kyphosis due to L1 vertebral fracture showed associated vertebral instability and pain resistant to conservative treatment.She underwent surgery for a one-stage anterior kypholectomy with spinal fusion. We performed an extrapleural approach. On the 4th post-operative day, the patient developed respiratory distress with decreased SpO2. Contrast-enhanced computed tomography (CT) revealed a left hemothorax with active bleeding. Revision surgery was performed to arrest the bleeding, and a large hematoma in the thoracic cavity was observed around the intercostal artery just below the skin incision, not around the surgical site.A man suffered from impaired activities of daily living caused by postural abnormalities due to severe kyphosis from vertebral fractures at the L1 and L2 vertebrae. Thus, we performed two-stage kypholectomy surgery. First, we performed posterior fixation with posterior facet resection. Then, corpectomy of the 1st and 2nd lumbar vertebrae through an anterior extrathoracic approach was performed. A CT scan on the 2nd post-operative day showed a massive hemopneumothorax, indicating persistent bleeding, and we performed a revision surgery to open the chest for additional hemostasis. Intraoperative findings showed a large hematoma, including reactive pleural effusion in the subcutaneous, retroperitoneal, and intrathoracic cavities. CONCLUSION: We experienced two patients who required thoracotomy hematoma removal after anterior spinal surgery. Intraoperative patronage and adequate hemostasis are necessary to avoid post-operative complications such as hemothorax and hemopneumothorax.