Safety and feasibility of intravenous administration of a single dose of allogenic-Muse cells to treat human cervical traumatic spinal cord injury: a clinical trial.

INTRODUCTION: Spinal cord injury (SCI) is a devastating injury and remains one of the largest medical and social burdens because of its intractable nature. According to the recent advances in stem cell biology, the possibility of spinal cord regeneration and functional restoration has been suggested by introducing appropriate stem cells. Multilineage-differentiating stress enduring (Muse) cells are a type of nontumorigenic endogenous reparative stem cell. The positive results of Muse cell transplantation for SCI was shown previously. As a first step for clinical application in human SCI, we conducted a clinical trial aiming to confirm the safety and feasibility of intravenously injected donor-Muse cells. METHODS: The study design of the current trial was a prospective, multicenter, nonrandomized, nonblinded, single-arm study. The clinical trial registration number was JRCT1080224764. Patients with a cervical SCI with a neurological level of injury C4 to C7 with the severity of modified Frankel classification B1 and B2 were included. A primary endpoint was set for safety and feasibility. Our protocol was approved by the PMDA, and the trial was funded by the Life Science Institute, Tokyo, Japan. The present clinical trial recruited 10 participants (8 males and 2 females) with an average age of 49.3 ± 21.2 years old. All 10 participants received a single dose of allogenic CL2020 (a total of 15 × 106 cells, 2.1-2.7 × 105 cells/kg of body weight), which is a Muse cell-based product produced from human mesenchymal stem cells, by an intravenous drip. RESULTS: There were two reported severe adverse events, both of which were determined to have no causal relationship with Muse cell treatment. The change in the ISNCSCI motor score, the activity of daily living and quality of life scores showed statistically significant improvements compared to those data at the time of CL2020 administration. CONCLUSION: In the present trial, no safety concerns were identified, and Muse cell product transplantation demonstrated good tolerability. Future clinical trials with appropriate study designs incorporating a control arm will clarify the definitive efficacy of single-dose allogenic Muse cell treatment with intravenous administration to treat SCI. TRIAL REGISTRATION: jRCT, JRCT1080224764. Registered 03 July 2019, https://jrct.niph.go.jp/latest-detail/jRCT1080224764 .

Development of a novel approach for restoration of the meniscus using silk-elastin in a rabbit meniscus injury model.

BACKGROUND: Limited healing potential of the meniscus remains a burden for the successful repair of meniscus injuries in the orthopaedic fields. Silk-elastin (SE) is a novel recombinant protein with favorable properties for wound healing. This proof-of-concept study aimed to investigate the therapeutic effect of silk-elastin in a rabbit meniscal defect model. METHODS: A migration assay using rabbit meniscus and synovial cells with various concentrations of SE in a culture medium was conducted to investigate the mechanism of meniscal healing by SE. Additionally, cylindrical defects with a 1.5 mm diameter were created at the anterior horn of the medial meniscus of rabbits. The animals were divided into three groups: 1) the Blank group; defect only, 2) the Col I group; implantation of type I atelocollagen sponge, and 3) the SE group; implantation of SE (150 mg/ml) sponge. Whole medial menisci were harvested at 4, 8, 12, and 24 weeks after surgery. Histological analyses including immunohistochemical staining were performed to assess meniscal healing. RESULTS: In vitro study, Migration assay demonstrated a significantly higher number of migrated cells only in synovial cells. Especially, the SE concentration of 10 µg/mL demonstrated the highest number of migrated cells compared with other concentrations. In vivo study, the SE group exhibited significantly higher Ishida scores than other groups at all time points. Furthermore, the SE group showed higher synovial coverage scores than the Col I group at 4 and 8 weeks. Immunohistochemical staining demonstrated higher type II collagen staining in the SE group compared to other groups at 12 weeks. Implanted SE was efficiently replaced by safranin-O staining positive tissue within 8 weeks. CONCLUSIONS: SE could effectively repair a meniscal defect by inducing coverage of synovial cells. SE has the potential to be a useful material for meniscal repair.

Differentiation of the Intradural Extramedullary Spinal Tumors, Schwannomas, and Meningiomas Utilizing the Contrast Ratio as a Quantitative Magnetic Resonance Imaging Method.

BACKGROUND: Schwannomas and meningiomas are the most common intradural extramedullary spinal tumors; however, differentiating between them using magnetic resonance imaging (MRI) is a frequent challenge. In this study, we aimed to investigate the use of the contrast ratio (CR) as a quantitative MRI method in the differentiation of schwannomas and meningiomas. METHODS: We analyzed the data of patients with intradural extramedullary spinal tumors who underwent surgery and were diagnosed with either schwannomas or meningiomas by histopathological analysis. Regions of interest were set for the entire spinal tumor on T2-weighted sagittal MRI. To obtain the CR values of spinal tumors (CRtumor), we used the signal intensity (SI) values of the tumor (SItumor) and spinal cord (SIcord) according to the following formula: [CRtumor = (SItumor-SIcord)/(SItumor+SIcord)]. RESULTS: The study included 50 patients (23 males and 27 females) with a mean age of 61.5 years old (11-85 years old). Histopathological analysis revealed that 33 and 17 patients were diagnosed with schwannomas and meningiomas, respectively. The mean CR values of the schwannomas and meningiomas were 0.3040 ± 0.1386 and 0.0173 ± 0.1929, respectively. The CR value of the schwannomas was statistically significantly higher than that of meningiomas (P < 0.01). The cutoff CR value obtained from the receiver operating characteristic curve was 0.143, with a specificity and sensitivity of 90.9% and 88.2%, respectively. Furthermore, the value for the area under the receiver operating characteristic curve was 0.925 (95% confidence interval: 0.852-0.998). CONCLUSIONS: The evaluation of CRs by using MRI to distinguish between schwannomas and meningiomas is a beneficial quantitative tool.

Short-segment spinal fusion for chronic low back pain with bone marrow edema adjacent to the vertebral endplate in adult spinal deformity.

PURPOSE: Corrective long spinal fusion is a widely accepted surgical method for patients with adult spinal deformities. However, instrumented long fusion is associated with a significant risk of complications. Therefore, we aimed to assess the success of short-segment spinal fusion, particularly for bone marrow edema (BME) adjacent to the vertebral endplate, in patients with low back pain (LBP) and spinal deformity. METHODS: A prospective study was performed at multiple hospitals wherein we monitored patients with spinal deformities and accompanying LBP. Patients aged ≥ 50 years with a minimum LBP severity score of 40 mm on the visual analog scale (VAS) were included in the study. We also included patients with lumbar BME on magnetic resonance imaging. Short spinal fusion was performed on segments with BME. Clinical evaluations of LBP on VAS and Oswestry Disability Index (ODI), and radiological parameters for sagittal vertical axis (SVA), pelvic incidence (PI), lumbar lordosis (LL) and pelvic tilt (PT) were carried out. RESULTS: Overall, 35 patients (22 men and 13 women), with a mean age of 66.7 years and a mean follow-up period of 32 months, were included in the study. The mean VAS and ODI scores were 72.4 mm and 49.0% before surgery and 25.5 mm and 29.9% at the final follow-up, respectively; these parameters significantly improved after surgery. The SVA, PI-LL, and PT scores were 70.1 mm, 20.9°, and 22.8° before surgery and 85.4 mm, 13.8°, and 22.7° at the final follow-up, respectively. The spinal alignment parameters did not change significantly after surgery. CONCLUSIONS: Short-segment spinal fusion is effective for treating LBP and spinal deformity with BME adjacent to the vertebral endplate without spinal correction.

Intradiscal Condoliase Injection Therapy for Recurrent Lumbar Disc Herniation: Case Series and Literature Review.

Background and objectives: Although chemonucleolysis with condoliase for lumbar disc herniation (LDH) has become common, few reports have described its application in the treatment of recurrent LDH. Therefore, this study aimed to evaluate the safety and efficacy of condoliase treatment in six patients with recurrent LDH and review the available literature on condoliase treatment for LDH. Materials and Methods: Six patients (four men and two women; mean age, 64.7 years) with recurrent LDH who were treated with condoliase at our hospital between 2019 and 2022 were included. The clinical records and images of the patients were retrospectively evaluated. In addition, the available English literature on condoliase treatment for LDH was retrieved and reviewed. Results: Among the six patients included in the study, three showed >50% improvement in leg pain after treatment, which is a lower efficacy rate than that in previous reports. In addition, two patients required surgery after treatment, which is a higher rate than that in previous reports. The mean intervertebral disc height significantly decreased from 8.4 mm before treatment to 6.9 mm after treatment, consistent with the results of previous studies. None of the cases showed Modic type I changes on magnetic resonance imaging. Conclusions: Although the efficacy of condoliase treatment for recurrent LDH may be lower than that for primary LDH, this treatment was found to be safe and applicable for recurrent LDH.

Sacral Stress Fracture in Athletes With Overuse: A Clinical Series of 11 Patients and Literature Review.

STUDY DESIGN: This was a narrative review. OBJECTIVES: The purpose of this study was to report the physical and radiologic characteristics of sacral stress fractures in 11 athletes and to review the current literature on sacral stress fractures. SUMMARY OF BACKGROUND DATA: Sacral stress fractures are rarely reported as a cause of low back pain in athletes. PATIENTS AND METHODS: We retrospectively analyzed 11 athlete patients with sacral stress fractures and low back pain. All patients received conservative treatments, such as rest from sporting activities and physical therapy. Clinical data, such as age, sex, athletic activity, region of tenderness, and duration of low back pain, and radiologic data, such as information from plain radiographs and fracture lines on magnetic resonance imaging (MRI), were evaluated. RESULTS: The study included 11 athlete patients (5 males and 6 females) with sacral stress fractures, and their mean age was 18.7 years (range, 15-38 y). The sports that caused the stress fractures were baseball, badminton, and basketball in 2 patients each and football, judo, marathon, volleyball, and dance in 1 patient each. All patients had tenderness on the sacrum. The mean duration of low back pain was 1.8 weeks (range, 1-4 wk). Fracture lines on MRI were observed only in the caudal-ventral part of the sacrum in 7 patients and extended from the inferolateral angle of the sacrum to the superior lateral sacral alar in 4 patients. CONCLUSIONS: The study findings demonstrated that MRI and tenderness were useful for detecting the presence of sacral stress fractures in athletes. Moreover, fracture lines in the sacrum may progress from the caudal-ventral part of the sacrum to the cranio-dorsal direction.

Vertebral osteomyelitis due to Mycobacterium abscessus subsp. massiliense with paravertebral abscess: A case report and review.

The incidence of vertebral osteomyelitis (VO) caused by non-tuberculosis mycobacteria (NTM) without immunocompetence is extremely rare. Herein, we reported on a case of VO caused by NTM. A 38-year-old man was admitted to our hospital with persisting low back and leg pain which had lasted for a year. Before coming to our hospital, the patient was treated with antibiotics and iliopsoas muscle drainage. The biopsy confirmed the presence of a NTM, Mycobacterium abscessus subsp. massiliense. Several tests were conducted which showed the infection had progressively increased, such as vertebral endplate destruction on plain radiography, computed tomography scan, and epidural and paraspinal muscle abscesses on magnetic resonance imaging. The patient underwent radical debridement, anterior intervertebral fusion with bone graft, and posterior instrumentation with antibiotic administration. A year later, the patient's low back and leg pain was relieved without any analgetic. VO due to NTM is rare but can be treated with multimodal therapy.

Balancing ability of patients with lumbar spinal canal stenosis.

PURPOSE: To determine the relationship between postural sway and the severity of lumbar spinal canal stenosis as well as the effect on postoperative improvement. METHODS: Stabilometry was performed before and 6 months after surgery in 52 patients (29 men and 23 women; mean age, 74.1 ± 7.8 years) who underwent decompression surgery for lumbar spinal canal stenosis. The environmental area (EA; the area surrounding the circumference of the stabilogram) and locus length per EA (L/EA) were evaluated. The patients were divided into moderate (n = 22) and severe (n = 30) groups according to the severity of canal stenosis. Patient characteristics and parameters were compared between the groups before and after surgery, including the visual analog scale (VAS) score for leg pain, Oswestry Disability Index (ODI), EA, and L/EA. In addition, factors affecting EA and L/EA were evaluated using multiple regression analysis. RESULTS: Age (p = 0.031), preoperative EA (p < 0.001), preoperative L/EA (p = 0.032), and sagittal vertical axis (p = 0.033) were significantly different between groups. The VAS score and ODI significantly improved postoperatively in both groups (p < 0.001). The EA significantly improved postoperatively only in the severe group (p < 0.001), whereas the L/EA did not significantly improve in either group. Multiple regression analysis showed that only the severity of canal stenosis was significantly associated with preoperative EA (p = 0.030), whereas age (p = 0.040) and severity of canal stenosis (p = 0.030) were significantly associated with preoperative L/EA. Diabetes was significantly associated with postoperative EA (p = 0.046) and L/EA (p = 0.030). CONCLUSION: The severity of canal stenosis affected abnormal postural sway, which improved after decompression surgery.

Prognostic factors of balloon kyphoplasty for osteoporotic vertebral fractures with diffuse idiopathic skeletal hyperostosis.

OBJECTIVE: The authors aimed to determine the poor prognostic factors of balloon kyphoplasty for the treatment of fractures of the most distal or distal-adjacent vertebrae in ankylosing spines with diffuse idiopathic skeletal hyperostosis (DISH). METHODS: Eighty-nine patients with fractures of the most distal or distal-adjacent vertebrae of ankylosing spines with DISH were included and divided into two groups: those with (n = 51) and without (n = 38) bone healing 6 months postoperatively. Clinical evaluation included age, sex, time from onset to surgery, the visual analog scale score for low-back pain, and the Oswestry Disability Index (ODI). The VAS scores and ODI were measured both preoperatively and at 6 months postoperatively. Radiological evaluations included bone density; wedge angles of the fractured vertebrae in the supine and sitting positions on lateral radiographs; differences in the wedge angles (change in wedge angle); and the amount of polymethylmethacrylate used. RESULTS: The preoperative ODI, vertebral wedge angles in the supine and sitting positions, change in wedge angle, and amount of polymethylmethacrylate were significantly different between the two groups and were significantly associated with delayed bone healing in univariate logistic regression analysis. Multivariate logistic regression analysis showed that only a change in the wedge angle was significantly associated with delayed healing, with a cutoff value of 10°, sensitivity of 84.2%, and specificity of 82.4%. CONCLUSIONS: Treatment with balloon kyphoplasty alone should be avoided in patients with a difference ≥ 10° in the wedge angle of the fractured vertebrae between the supine and sitting positions.

Differentiating Neurodegenerative Disease from Compressive Cervical Myelopathy Using Motor Evoked Potentials.

STUDY DESIGN: A retrospective case-control study. OBJECTIVE: To differentiate neurodegenerative diseases from compressive cervical myelopathy (CCM) using motor evoked potentials (MEPs). SUMMARY OF BACKGROUND DATA: When considering surgery for CCM, it may be necessary to differentiate the condition from a neurodegenerative disease. METHODS: A total of 30 healthy volunteers, 52 typical CCM patients with single-level compression of the spinal cord at C4-5 or C5-6, seven patients with amyotrophic lateral sclerosis (ALS), and 12 patients with demyelinating disease of the central nervous system (DDC), including 11 patients with multiple sclerosis and one patient with neuromyelitis optica spectrum disorder, formed our study population. MEPs were recorded from the bilateral abductor digiti minimi (ADM) and abductor hallucis (AH) muscles using transcranial magnetic stimulation and electrical stimulation of the ulnar and tibial nerves. Central motor conduction time (CMCT), peripheral conduction time, amplitude of MEPs, and frequency of F-waves were evaluated. Receiver operating characteristic (ROC) curve analysis was used to determine the cut-off value for distinguishing between CCM and ALS. RESULTS: Significant differences were observed in the amplitude of MEPs and frequency of F-waves evoked by peripheral nerve stimulation between patients with CCM and ALS. The MEP amplitude of AH was more accurate in differentiating between the two diseases compared to ADM (cut-off value, 11.2mV, sensitivity, 87.5%; specificity, 85.7%). All seven patients with ALS showed reduced frequency of F waves from ADM or AH, but none of the healthy volunteers or patients with other diseases demonstrated this finding. Moreover, there were no significant differences between CCM and DDC in any of the assessments. CONCLUSION: The amplitude of MEPs and frequency of F waves evoked by peripheral nerve stimulation could be helpful in differentiating ALS from CCM.

Microcervical Foraminotomy for Cervical Juxtafacet Cysts: Case Series and Literature Review.

BACKGROUND: Juxtafacet cysts are located near or contiguous with the facet joints, and their occurrence is rare in the cervical spine. We report 4 cases of cervical juxtafacet cysts operated by microcervical foraminotomy (MCF) or a combination of MCF and laminoplasty. We simultaneously review previously reported cases in terms of location, clinical findings, and surgical technique. METHODS: Among the patients who underwent spine surgery at our hospital from 2015 to 2019, 4 had cervical juxtafacet cysts. The images and clinical records of the patients were retrospectively assessed. Relevant previous English literature was searched and reviewed using PubMed. RESULTS: In our series, all 4 patients presented with unilateral upper extremity muscle weakness preoperatively. Two patients underwent MCF, and the other 2 underwent a combination of MCF and laminoplasty with resection of the cyst. All showed improvement in muscle strength. In previously reported cases, the rate of muscle weakness was high. A review of previous cases showed that 75 of 139 patients had cysts at C7-T1. The most common surgical techniques consisted of a hemilaminectomy or laminectomy with the addition of posterior fusion in 28 patients. The number of male patients was twice that of female patients; however, the male-to-female ratio was almost the same in patients with cysts in C7-T1. On pathological diagnosis, there were 3 times more synovial cysts than ganglion cysts. The percentage of synovial cysts was higher in patients with radiculopathy, and the percentage of ganglion cysts was higher in patients with myelopathy. CONCLUSIONS: Cervical juxtafacet cysts tend to occur in C7-T1 and cause muscle weakness. Surgical therapy is strongly recommended due to good postoperative improvement. CLINICAL RELEVANCE: The results of this study suggest that microcervical foraminotomy for cervical juxtafacet cysts can provide favorable symptomatic improvement.

Foramen Magnum Decompression with Outer Dura Matter Layer Resection for Chiari Type I Malformation: Factors Correlated with Syrinx Reduction.

STUDY DESIGN: A retrospective cohort study. PURPOSE: We aimed to investigate the surgical results of foramen magnum decompression (FMD) to identify the potential factors associated with syrinx reduction in Chiari malformation type I (CMI). OVERVIEW OF LITERATURE: The predictive value of preoperative factors for syrinx reduction in patients with CMI remains debatable. METHODS: We enrolled patients who underwent microscopic FMD with outer dural layer resection for CMI. The distance from the tip of the cerebellar tonsil to the C2 vertebral endplate on sagittal magnetic resonance imaging (MRI) was defined as the tonsillar distance (TD). Patients who showed a >20% syrinx diameter reduction on the 1-year follow-up MRI were defined as the syrinx reduction group while the others were categorized in the syrinx nonreduction group. Patients with syringomyelia were categorized into the clinically improved and unimproved groups using the Chicago Chiari Outcome Scale. The imaging and clinical parameters were evaluated pre- and postoperatively. RESULTS: This study included 25 patients of whom 19 (76.0%) had syringomyelia. At the 1-year follow-up, the syrinx diameter had decreased in 11 patients (57.8%). The increased TD significantly differed between the syrinx reduction and nonreduction groups. At the 1-year follow-up, 12 and seven patients with syringomyelia were categorized into the clinically improved and unimproved groups, respectively. The clinically improved and unimproved groups showed significant differences in the mean age and increased TD. CONCLUSIONS: Postoperative syrinx reduction was significantly correlated with the upward shifting of the cerebellar tonsil in patients with CMI. Our quantitative evaluation of the alterations in hindbrain position after FMD was easily performed and reflects the clinical outcomes.

Comparison of the electrophysiological characteristics of tight filum terminale and tethered cord syndrome.

PURPOSE: This study aims to characterize tight filum terminale (TFT) in motor evoked potential (MEP) testing by comparing TFT patients with both tethered cord syndrome (TCS) patients and healthy subjects. METHODS: Fifty TFT patients, 18 TCS patients, and 35 healthy volunteers participated in this study. We recorded MEPs following transcranial magnetic stimulation from the bilateral abductor hallucis muscles as well as compound muscle action potentials and F-waves evoked by electrical stimulation of the tibial nerve from the bilateral abductor pollicis brevis muscles. The peripheral conduction time (PCT) was calculated from the latency of the compound action potential and F-wave. Furthermore, the central motor conduction time (CMCT) was calculated by subtracting PCT from MEP latency. RESULTS: TFT and TCS patients had a significantly longer MEP latency than healthy subjects. PCT in TFT patients was significantly longer than those in TCS patients or healthy subjects. Using the cutoff values for PCT, we were able to diagnose patients with TFT patients with a sensitivity of 72.0% and a specificity of 91.4%. CONCLUSION: Prolonged PCT in the MEP test may be a useful indicator for TFT and suggests that MEP may be used as an adjunct diagnostic tool for TFT.

Spinous Process Fractures in Osteoporotic Vertebral Fractures: A Cross-Sectional Study.

Introduction: The purpose of this study was to assess radiological features and clinical scores of osteoporotic vertebral fracture (OVF) accompanied by spinous process fracture (SPF). Methods: We included painful patients with single-level OVF with intravertebral cleft. SPF was detected using magnetic resonance imaging (MRI) and/or computed tomography (CT). The plain radiographs of the vertebral fractures were evaluated based on the wedging angle of the fractured vertebrae and vertebral instability. We investigated the clinical parameters of age, gender, visual analog scale (VAS) score for low back pain (LBP), Oswestry Disability Index (ODI), and the period from the onset of acute fracture. Results: MRI and/or CT indicated among 195 patients of OVF with LBP, 41 patients (20.5%) had SPFs. SPFs were observed one level above the fractured vertebral body in 35 patients (85.4%) and at the same level as the fractured vertebral body in 6 patients (14.6%). The prevalence of vertebral fracture of thoracic spine in the SPF-positive group was significantly greater than that in the SPF-negative group. There were no significant differences in age, gender, VAS, ODI, the time period from the onset of acute LBP, wedging angle, and vertebral instability between the presence or absence of SPFs. Conclusions: SPFs occurred in 20.5% of patients with OVF and LBP. In addition, SPFs often occurred one level above the fractured vertebra, and SPFs with OVF tended to be located in the thoracic spine.

Radiographic Factors for Adjacent Vertebral Fractures and Cement Loosening Following Balloon Kyphoplasty in Patients with Osteoporotic Vertebral Fractures.

Introduction: Balloon kyphoplasty (BKP) is a minimally invasive surgical approach for the treatment of osteoporotic vertebral fractures (OVF). Some risks have been reported after treatment with BKP; therefore, it is necessary to determine when BKP does not work. Thus, in this study, we aim to clarify the radiographic predictors of secondary vertebral fractures and cement loosening after BKP for OVF. Methods: This study enrolled patients with single-level OVF at the thoracolumbar junction (T11-L2) who underwent BKP for the first time between January 2011 and March 2014. The clinical outcomes were evaluated using the visual analog scale (VAS) and a modified Oswestry Disability Index (ODI) at 1 week and 1, 3, 6, and 12 months after surgery. Radiographic assessments were performed preoperatively and within 1 year after BKP using plain radiography and computed tomography. Results: The 85 patients who met the inclusion criteria underwent BKP. The average age of participants (21 men, 64 women) was 77.8 years (range, 57-92 years). Postoperative VAS and ODI scores were all significantly better than preoperative scores. Polymethyl methacrylate (PMMA)-cement leakage was observed in 18 patients (21.2%) but was asymptomatic in all cases. Secondary vertebral fractures were detected in 20 patients (23.5%), including adjacent levels in 15 patients (17.6%) and non-adjacent levels in 5 patients (5.9%). Rostral bridging osteophyte formation was found to be significantly associated with the occurrence of adjacent vertebral fractures (odds ratio 12.746; p=0.010). PMMA-cement loosening was observed in three patients (3.5%). A high prevalence (100%) of bridging osteophytes, vacuum clefts, and spinous process fractures was observed in patients with PMMA-cement loosening. PMMA-cement loosening was found in 3 out of 10 patients with all three of these factors. Conclusions: Rostral bridging osteophyte formation was determined to be a risk factor for both adjacent vertebral fractures and PMMA-cement loosening.Level of Evidence: 3.

Development of a rat model with lumbar vertebral endplate lesion.

PURPOSE: Vertebral endplate lesion (EPL) caused by severe disc degeneration is associated with low back pain. However, there is no suitable animal model to elucidate the pathophysiology of EPL. This study aimed to develop a rat model of EPL and evaluate rat behavior and imaging and histological findings. METHODS: The L4-5 intervertebral discs of Sprague-Dawley rats were transperitoneally removed, except for the outer annulus fibrosus and cartilage endplate, in the EPL group. The L4-5 discs were not removed and simply exposed in the sham group. Changes around the vertebral endplate on magnetic resonance imaging (MRI) and computed tomography (CT) were evaluated. Additionally, pain-related behavioral and histological assessments were performed. RESULTS: In the EPL group, a low-signal area around the vertebral endplate was observed on T1-weighted and T2-weighted fat-saturated MRI at 8 weeks or later after surgery. In the same group, CT showed osteosclerosis around the vertebral endplate at 12 weeks after surgery. The sham group did not show abnormal imaging features on the MRI and CT. Behavioral evaluation showed that the EPL group had a significantly longer grooming time than the sham group. Conversely, the 12-week postoperative locomotion time and the 1- and 12-week postoperative standing times were significantly shorter in the EPL group than in the sham group. Histological evaluation showed a high degree of vertebral endplate degeneration and an increased number of osteoclasts and proportion of nerve fibers expressing calcitonin gene-related peptide in the EPL group compared to those in the sham group. CONCLUSION: Our rat EPL model showed pain-related behavioral patterns and an increased expression of pain-related neuropeptide. This model could contribute to the study of the pathophysiology of EPL and will help in the treatment of low back pain in the future.

Prognostic factors for spontaneous spinal epidural hematoma: a multicenter case-control study.

BACKGROUND: To determine the optimal treatment for spontaneous spinal epidural hematoma (SSEH). The aim of this study was to identify factors associated with SSEH. METHODS: In 62 patients with SSEH, several patient-related parameters were analyzed as candidate factors associated with Frankel grade before treatment or at the last follow-up. These parameters were compared between patients with and without surgery. In addition, multivariate ordinal logistic regression analysis was used to identify factors significantly associated with Frankel's grade before treatment or at the last follow-up. RESULTS: There were significant differences in age, location of the hematoma, and Frankel grade before treatment and at the last follow-up between surgical and nonsurgical cases in all patients, but there were no significant differences in any of these parameters when comparing patients with pre-treatment Frankel grade C. The location of the hematoma was significantly associated with the severity of paralysis before treatment. In surgical cases, the time from onset to surgery and the location of the hematoma was significantly associated with the prognosis. When the time from onset to surgery was evaluated using the criteria of 12, 24, and 48 h, 24 and 48 h had a significant impact on the prognosis. In the analysis of nonsurgical cases, only the vertical size of the hematoma was significantly associated with prognosis. CONCLUSION: The time from onset to surgery and the location of the hematoma were prognostic factors in surgical cases, while the vertical size of the hematoma was a prognostic factor in nonsurgical cases.

Vertebral osteomyelitis caused by Mycobacteroides abscessus subsp. abscessus resulting in spinal cord injury due to vertebral body fractures.

Nontuberculous mycobacteria (NTM) rarely cause vertebral osteomyelitis; however, the clinical characteristics of vertebral osteomyelitis caused by NTM are poorly understood due to its rarity. A 74-year-old man with lung cancer was treated with prednisolone for immune checkpoint inhibitor-associated immune-related adverse events. He had been experiencing mild back pain without febrile episodes for five months, and was admitted to the hospital for worsening back pain and progressive paraplegia. Magnetic resonance imaging showed spinal cord compression at T4-5 due to fractures of the T5 and T7 vertebral bodies. The culture of a sample of pus from the T7 vertebral body obtained at the time of spinal fusion surgery yielded the Mycobacteroides abscessus (M. abscessus) complex. The patient was diagnosed with vertebral osteomyelitis caused by M. abscessus complex and treated with clarithromycin, amikacin, and imipenem; clarithromycin was later replaced by sitafloxacin because of inducible macrolide resistance. However, his neurologic deficits were irreversible, and he died due to a deteriorating general condition. The strain was identified up to subspecies level as M. abscessus subsp. abscessus by hsp65 and rpoB sequencing and nucleic acid chromatography. Although vertebral osteomyelitis due to NTM is rare, delayed diagnosis can lead to serious complications or poor outcomes. A prolonged clinical course, less frequent fever, vertebral destruction or spinal deformity, neurological deficits, or immunosuppressed conditions might be suggestive of NTM vertebral osteomyelitis.

Surgical outcomes of cervical myelopathy in patients with athetoid cerebral palsy.

PURPOSE: Surgical treatment for cervical myelopathy with athetoid cerebral palsy remains unestablished. Instrumented fusion is reported to have good clinical results; however, there are no data of decompression surgery for this pathology in recent years. This study aimed to assess the surgical outcomes of laminoplasty with or without posterior instrumented fusion for cervical myelopathy in patients with athetoid cerebral palsy. METHODS: A multi-centre surgical series of patients with cervical myelopathy and athetoid cerebral palsy were enrolled in this study. All patients showed symptoms and signs suggestive of cervical myelopathy and underwent laminoplasty with or without instrumented fusion. The Japanese Orthopaedic Association (JOA) score, Barthel index (BI), and changes in the C2-C7 sagittal Cobb angle in the lateral plain radiograph were analysed. RESULTS: There were 25 patients (16 men and 9 women; mean age, 54.4 ± 10.8 years) with cervical myelopathy and athetoid cerebral palsy who underwent surgical treatment. The mean follow-up period was 41.9 ± 35.6 months. Overall, the BI significantly improved after surgery, whereas the JOA score and C2-C7 angle did not improve postoperatively. The recovery rate of the JOA score in the laminoplasty group was significantly higher than that of the fusion group (P = 0.02). CONCLUSIONS: Cervical laminoplasty with or without instrumented fusion for treating cervical myelopathy due to athetoid cerebral palsy is effective in improving activities of daily living. Cervical laminoplasty may be an effective and less invasive surgical method for selective patients, especially for those with small involuntary movements and no remarkable cervical kyphosis nor instability.