Spinal subdural hematoma with sudden onset of paraplegia in a patient on oral anticoagulant therapy.

Spinal subdural hematoma is uncommon but may become more prevalent with increasing anticoagulant use. Early diagnosis from symptoms like lower back pain and leg paralysis is crucial for timely intervention.

Denosumab vs. bisphosphonates in primary osteoporosis: a meta-analysis of comparative safety in randomized controlled trials.

Denosumab and bisphosphonates for primary osteoporosis are generally well-tolerated, but their comparative safety remains unclear. We aimed to explore the comparative safety of denosumab and bisphosphonates in primary osteoporosis. Databases such as PubMed and Google Scholar were searched for relevant peer-reviewed randomized controlled trials published in English (as of December 2023). Trials comparing adverse events (AE) between denosumab and bisphosphonates in patients with primary osteoporosis were investigated. Data were pooled using a fixed- or random-effects model to determine the risk ratios (RR) and 95% confidence intervals (CIs) for various AEs in patients treated with denosumab in comparison to patients treated with bisphosphonates. Eleven trials (5,545 patients; follow-up period: 12-24 months) were included in this meta-analysis. All trials had a risk of bias (e.g., reporting bias linked to secondary endpoints and selection bias linked to random allocation). In comparison to bisphosphonates, denosumab was significantly associated with less withdrawal due to AEs (RR = 0.49; 95% CI 0.34-0.71), more five-point major adverse cardiovascular events (RR = 2.05; 95% CI 1.03-4.09), more cardiovascular AEs (RR = 1.61; 95% CI 1.07-2.41), more infections (RR = 1.14; 95% CI 1.02-1.27), more upper respiratory tract infections (RR = 1.56; 95% CI 1.08-2.25), less vertebral fractures (RR = 0.54; 95% CI 0.31-0.93), and less abdominal pain (RR = 0.44;95% CI 0.22-0.87). We explored the comparative safety of denosumab and bisphosphonates for primary osteoporosis, some of which could be attributed to their beneficial effects. However, all trials had a risk of bias. Further investigations are required to confirm our results.

A new era in the management of spinal metastasis.

Despite the recent advances in cancer treatment, the incidence of patients with spinal metastases continues to grow along with the total number of cancer patients. Spinal metastases can significantly impair activities of daily living (ADL) and quality of life (QOL), compared with other types of bone metastases, as they are characterized with severe pain and paralysis caused by skeletal-related events. Reduced ADL can also lead to treatment limitations as certain anticancer agents and radiation therapy are not compatible treatments; thus, leading to a shorter life expectancy. Consequently, maintaining ADLs in patients with spinal metastases is paramount, and spine surgeons have an integral role to play in this regard. However, neurosurgeon, orthopedic and spinal surgeons in Japan do not have a proactive treatment approach to spinal metastases, which may prevent them from providing appropriate treatment when needed (clinical inertia). To overcome such endemic inertia, it is essential for 1) spine surgeons to understand and be more actively involved with patients with musculoskeletal disorders (cancer locomo) and cancer patients; 2) the adoption of a multidisciplinary approach (coordination and meetings not only with the attending oncologist but also with spine surgeons, radiologists, rehabilitation specialists, and other professionals) to preemptive treatment such as medication, radiotherapy, and surgical treatment; and 3) the integration of the latest findings associated with minimally invasive spinal treatments that have expanded the indications for treatment of spinal metastases and improved treatment outcomes. This heralds a new era in the management of spinal metastases.

Academic Engagement of Women as Orthopaedic Surgeons at the Annual Meetings of the Japanese Orthopaedic Association From 2012 to 2022.

BACKGROUND: Higher gender diversity correlates with higher patient satisfaction, higher-quality medical education, increased research productivity, and higher revenues. Although the field of Japanese orthopaedic surgery includes the lowest proportion of women and lags in gender diversity, reports on the current gender diversity status in academic activities are scarce. We investigated changes in women's participation in academic activities at the Japanese Orthopaedic Association (JOA) annual meetings over the past 11 years. METHODS: Data on the percentage of women in the JOA membership during 2012-2022 were analyzed to ascertain the proportion of women as first authors of oral and poster presentations, abstract reviewers, invited lecturers, seminar lecturers, general abstract oral chairpersons, symposium chairpersons, and speakers. Regarding the ratio of women among the JOA members during 2012-2022, we relied on data provided by the JOA. Data related to other categories were collected from the abstract book presented at the JOA Annual Meetings between 2012 and 2022. We analyzed the time trend for women's proportions using the Cochran-Armitage trend test. A p-value < 0.05 was considered statistically significant. RESULTS: During 2012-2022, the percentage of female members (4.9-6.7%), poster first authors (2.7-4.3%), abstract reviewers (0-1.5%), general abstract oral chairpersons (0-2.3%), symposium chairpersons (0-3.6%), and symposium speakers (1.6-6.8%) had increased significantly (p < 0.05). Oral first authors (2.2-4.1%), invited lecturers (0-6.8%), or seminar lecturers (0%-6.7%) showed no trend. Women engaged in academic activities at all annual association meetings did not exceed the women's proportion among the association members. CONCLUSION: Although the proportion of women members of the JOA has gradually increased and more women are involved in its annual meetings, the proportion of female presenters, invited speakers, symposiasts, and chairpersons of oral and poster presentations is generally lower than that of women as JOA members. Members should be asked to raise awareness, including more active education of women as physicians in educational institutions and the creation of positive actions to select women as physicians for more important roles (chairpersons, educational speakers, and symposiasts) in the organization of annual meetings.

The Usefulness of Deep Tendon Reflexes in the Diagnosis of Lumbar Spine Diseases: A Narrative Review.

The deep tendon reflex (DTR) is a more objective indicator than sensory and muscle assessments for lumbar spine disorders. Further, unlike sensory and muscle assessments that require patient cooperation, the DTR can be assessed even in patients with impaired consciousness or cognition. Therefore, DTR assessment with a hammer is an essential neurological test for lumbar spinal diseases. However, despite the usefulness of DTR assessment, few reports have described the significance of increased, diminished, or absent deep lower extremity reflexes in lumbar spine diseases. This review outlines the history of DTR of the lower limbs and describes the techniques, evaluation, and interpretation of DTR for the diagnosis of lumbar spine diseases. The patellar tendon reflex (PTR) was the first parameter of lower extremity DTR identified to have clinical usefulness, followed by the Achilles tendon reflex (ATR), pathological reflexes (Babinski reflex), and reflex enhancement (Jendrassik maneuver). They have now become an integral part of clinical examination. To determine whether an increase or decrease in DTR is pathological, it is necessary to determine left-right differences, differences between the upper and lower extremities, and the overall balance of the limb. There are several critical limitations and pitfalls in interpreting DTRs for lumbar spine diseases. Attention should be paid to examiner and patient factors that make the DTR assessment less objective. When there is a discrepancy between clinical and imaging findings and the level of the lumbosacral nerve root disorder is difficult to diagnose, the presence of a lumbosacral transitional vertebra, nerve root malformation, or furcal nerve should be considered. In addition, assessing the DTR after the gait loading test and standing extension loading test, which induce lumbosacral neuropathy, will help provide a rationale for the diagnosis.

Perioperative Cerebrovascular Accidents in Spine Surgery: A Retrospective Descriptive Study and A Systematic Review with Meta-Analysis.

Introduction: Perioperative cerebrovascular accidents (CVAs) related to spine surgery, although rare, can lead to significant disabilities. More studies on spine surgeries are required to identify those at risk of perioperative CVAs. The characteristics and outcomes of patients that experienced CVAs during spine surgery were assessed through a retrospective descriptive study and meta-analysis. Methods: Patients aged ≥18 years who underwent spine surgery under general anesthesia at a hospital between April 2011 and March 2023 were examined. Of the 2,391 initially identified patients, 2,346 were included after excluding 45 who underwent debridement for surgical site infections. Subsequently, a meta-analysis including the present retrospective descriptive study was conducted. Databases such as PubMed and Google Scholar were searched for original peer-reviewed articles written in English. Results: Of the 2,346 patients, 4 (0.17%) (three men, one woman) exhibited perioperative CVAs associated with spine surgery. The CVAs were diverse in nature: one case of cerebral hemorrhage resulting from dural injury during posterior occipitocervical fusion, two cases of cerebral infarctions after lumbar laminectomy and anterior thoracic fusion due to anticoagulant discontinuation, and one case of posterior reversible encephalopathy syndrome following microscopic lumbar discectomy due to gestational hypertension. The subsequent meta-analysis included three studies (n=186,860). It showed several risk factors for perioperative CVAs, including cervical level (pooled odds ratio [OR]=1.33), hypertension (pooled OR=2.27), atrial fibrillation (pooled OR=8.78), history of heart disease (pooled OR=2.47), and diabetes (pooled OR=2.13). Conclusions: It was speculated that the potential risk factors for the four perioperative CVA cases of spine surgery in this retrospective descriptive study were intraoperative dural injury, preoperative anticoagulant discontinuation, and gestational hypertension history. The meta-analysis revealed that cervical spine surgery, hypertension, atrial fibrillation, heart disease, and diabetes increased the CVA risk. This highlights the need for risk assessment, preoperative optimization, and postoperative care to reduce spine surgery-associated perioperative CVAs.

Analyzing lumbar vertebral shape and alignment in female patients with degenerative spondylolisthesis: Comparisons with spinal stenosis and risk factor exploration.

PURPOSE: This study aimed to examine the vertebral body shape characteristics and spondylopelvic alignment in L4 degenerative spondylolisthesis (DS) as well as the risk factors for the development of DS. METHODS: This cross-sectional study compared vertebral morphology and sagittal spinopelvic alignment in female patients with lumbar DS and lumbar spinal stenosis (LSS). The degree of lumbar lordosis (LL), pelvic incidence (PI), cross-sectional area (CSA), and vertebral body height ratio (ha/hp) of the lumbar spine were compared using full-length spine radiographs and computed tomography in 60 females with DS and in 60 women with LSS. RESULTS: No significant differences in age or body mass index were observed between the two groups; however, the DS and LSS groups significantly differed in PI (mean, 58.9±10.8 vs. 47.2±11.6, P < 0.001), L4 CSA (mean, 1,166.2 m2 vs. 1,242.0 m2, P = 0.002) and ha/hp (mean, 1.134 vs. 1.007, P < 0.001). The L4 ha/hp was significantly higher in the DS group than in the LSS group. Additionally, LL values were negatively correlated with vertebral L5 CSA in the DS group (r = -0.28, P < 0.05). The LSS and DS groups demonstrated positive correlations between LL and L2, L3, and L4 ha/hp (r = 0.331, 0.267, and 0.317; P < 0.01, < 0.05, and < 0.05, respectively) and between LL and L4 and L5 ha/hp (r = 0.333, 0.331; P < 0.01, respectively). Multivariate regression analyses revealed that PI and ha/hp ratio may be independent predictors of DS development. CONCLUSION: The DS group had significantly larger LL, PI, and L4 ha/hp and smaller L4 CSA than the LSS group. The lumbar vertebral body shape and sagittal spinopelvic alignment in females might be independent predictors of DS development.

Adjacent vertebral fractures in the lumbar and thoracic spine after balloon kyphoplasty: A finite element analysis.

The purpose of the present study was to mechanically verify after vertebral augmentation (AVA) scores using a finite element method (FEM) with accurate material constants of balloon kyphoplasty (BKP) cement. Representative cases with AVA scores of 1 (case 1), 3 (case 2), and 5 (case 3) among patients with vertebral body fractures who underwent BKP were analyzed. A FEM model consisting of 5 vertebral bodies was created, including the injured vertebral body in each case. The amount of displacement for each load (up to 4000 N) between the upper and lower vertebral bodies of each model was measured. Young modulus of the BKP cement was calculated from actual measurements using the EZ-Test EZ-S (Shimadzu Corporation, Kyoto, Japan). In all cases, the number of shell elements (209,296-299,876), solid elements (1913,029-2417,671), and nodes (387,848-487,756) were similar, indicating that FEM modeling was comparable among the cases. Young modulus of BKP cement, calculated using EZ-Test EZ-S, was 572 MPa. Fractures were detected by compressive forces of 3300 N (upper) and 3300 N (lower), 3000 N (upper) and 3100 N (lower), and 1200 N (upper) and 1200 N (lower) in cases 1, 2, and 3, respectively. The AVA scoring system was mechanically verified using the accurate material constants of BKP cement. A multicenter survey and external validation are therefore required for the clinical implementation of the AVA score.

Conservative management of spontaneous spinal epidural hematoma: A case report with favorable prognosis.

Sudden spinal epidural hematoma (SSEH) is relatively rare. Sudden pain from the neck to the back and subsequent extremity paralysis necessitate immediate head and cervical magnetic resonance imaging or computed tomography, keeping SSEH in mind. Although surgery is recommended for progressive paralysis, conservative treatment is indicated for mildly symptomatic cases.

Biomechanical Effect of Distal Tibial Oblique Osteotomy: A Preliminary Finite-Element Analysis.

BACKGROUND: The biomechanical effect of distal tibial oblique osteotomy (DTOO) on osteoarthritic ankles has not been investigated. Using finite element (FE) models, we aimed to elucidate the effect of DTOO on the ankle contact pressure (CP) distribution. METHODS: This study included two patients with ankle osteoarthritis who underwent DTOO and one asymptomatic control. Patient-specific FE models were reconstructed by matching standing radiographs with supine computed tomography scans. The joint contact area (CA) and maximum CP on the articular surface of the talus were calculated before and after DTOO and compared with those of the control. RESULTS: In the control, the CA was 584 mm2 and the maximum CP was 2.6 MPa. In case 1, the CA increased by 125% from 166 mm2 preoperatively to 375 mm2 postoperatively, accompanied by a 36% decrease in the maximum CP from 9.8 MPa to 6.3 MPa. Similarly, in case 2, the CA increased by 46% from 301 mm2 to 439 mm2, accompanied by a 27% decrease in the maximum CP from 6.7 MPa to 4.9 MPa. CONCLUSIONS: This study suggests DTOO improves the biomechanics of the ankle, but not sufficiently compared to the control. This analytical approach may enhance understanding of ankle pathophysiology and assist in the design of the ideal corrective osteotomy.

Infected charcot spine.

Patients with an infected charcot spine (ICS) may experience little or no back pain despite severe vertebral destruction. Understanding the pathophysiology underlying ICS and its differential diagnoses is crucial for its accurate diagnosis. Worsening symptoms of chronic charcot spine should raise suspicions of an infection.

Time elapsed from definitive diagnosis to surgery for osteonecrosis of the femoral head: a nationwide observational study in Japan.

OBJECTIVES: This study documents the time elapsed from the diagnosis of osteonecrosis of the femoral head (ONFH) to surgery, exploring the factors that influence ONFH severity. DESIGN: Retrospective observational study of a nationwide database. SETTING: The Kaplan-Meier method with log-rank tests was applied to examine the period from definitive diagnosis of ONFH to surgery using any surgery as the end point. For bilateral cases, the date of the first surgery was the endpoint. PARTICIPANTS: This study included 2074 ONFH cases registered in 34 university hospitals and highly specialised hospitals of the multicentre sentinel monitoring system of the Japanese Investigation Committee between 1997 and 2018. MAIN OUTCOME MEASURE: The primary outcome was the time from diagnosis to surgery. The secondary outcome was the proportion of subjects remaining without surgery at 3, 6 and 9 months, and at 1, 2 and 5 years after diagnosis. RESULTS: The median time to surgery was 9 months (IQR 4-22 months) after diagnosis of ONFH. The time to surgery was significantly shorter in the alcohol alone group and the combined corticosteroid and alcohol group than in the corticosteroid alone group (p=0.018 and p<0.001, respectively), in early stage ONFH with no or mild joint destruction (stages II and III, p<0.001), and with joint preserving surgery (p<0.001). The proportion without surgery was 75.8% at 3 months, 59.6% at 6 months, 48.2% at 9 months, 40.5% at 1 year, 22.2% at 2 years and 8.3% at 5 years. CONCLUSION: ONFH has been considered to be an intractable disease that often requires surgical treatment, but the fact that surgery was performed in more than half of the patients within 9 months from diagnosis suggests severe disease with a significant clinical impact. TRIAL REGISTRATION NUMBER: Chiba University ID1049.

A view on the skin-bone axis: unraveling similarities and potential of crosstalk.

The phrase "skin as a mirror of internal medicine," which means that the skin reflects many of the diseases of the internal organs, is a well-known notion. Despite the phenotypic differences between the soft skin and hard bone, the skin and bone are highly associated. Skin and bone consist of fibroblasts and osteoblasts, respectively, which secrete collagen and are involved in synthesis, while Langerhans cells and osteoclasts control turnover. Moreover, the quality and quantity of collagen in the skin and bone may be modified by aging, inflammation, estrogen, diabetes, and glucocorticoids. Skin and bone collagen are pathologically modified by aging, drugs, and metabolic diseases, such as diabetes. The structural similarities between the skin and bone and the crosstalk controlling their mutual pathological effects have led to the advocacy of the skin-bone axis. Thus, the skin may mirror the health of the bones and conversely, the condition of the skin may be reflected in the bones. From the perspective of the skin-bone axis, the similarities between skin and bone anatomy, function, and pathology, as well as the crosstalk between the two, are discussed in this review. A thorough elucidation of the pathways governing the skin-bone axis crosstalk would enhance our understanding of disease pathophysiology, facilitating the development of new diagnostics and therapies for skin collagen-induced bone disease and of new osteoporosis diagnostics and therapies that enhance skin collagen to increase bone quality and density.

The first case of methotrexate-associated lymphoproliferative disorder in the sacrum: a case report.

Methotrexate (MTX) is a drug used for treating rheumatoid arthritis. Recently, the reported incidence of methotrexate-associated lymphoproliferative disease (MTX-LPD) has increased, especially in Japan. Extranodal involvement is observed in half of MTX-LPD cases. However, only a few spinal lesions have been reported, with none in the sacrum. Additionally, Epstein-Barr virus (EBV) infection has also been implicated in the pathogenesis of MTX-LPD. Herein, we describe the case of a 74-year-old woman with MTX-LPD in the sacral spine who complained of severe back pain and nocturnal pain. Radiographs revealed a tumour on the right wing of the sacrum and a positive EBV immunoglobulin G antibody titre. MTX-LPD was suspected based on imaging findings and a history of MTX administration. A pathological examination was performed on the CT-guided biopsy specimen. The histopathological diagnosis was MTX-LPD, and MTX was discontinued. Three months after MTX administration ended, the tumour tended to shrink, and 1 year later, significant tumour shrinkage was observed. This experience suggests that MTX-LPD can be treated by discontinuing MTX administration. Therefore, early and accurate diagnosis is required, as is avoiding unnecessary treatment such as surgery. MTX-LPD should be considered, especially in spinal origin tumours in EBV-infected patients on MTX.

Insights and preventive approaches of rod erosion in the occipital bone after complex posterior cervical spine surgery for destructive spondyloarthropathy: A case report.

RATIONALE: Complications of rod migration into the occipital bone after upper cervical fusion are very rare. No other cases have been reported, especially when associated with destructive spondyloarthropathy (DSA). The purpose of this case report is to remind clinicians of the risk of rod migration in cervical spine surgery in patients with DSA and to provide information on its causes, countermeasures, and treatment. PATIENT CONCERN: This case report presents the clinical course of a 61-year-old female patient with chronic kidney disease that required hemodialysis. DIAGNOSIS, INTERVENTION, OUTCOMES: The patient was diagnosed DSA involving the cervical spine. Initial treatment involved a halo vest, followed by anterior cervical corpectomy and fusion spanning from C5 to Th1. However, subsequent complications, including C5 fractures, kyphotic cervical alignment, and rod migration into the occipital bone, lead to multistage surgical interventions. This case highlights the challenges in managing DSA, the significance of optimal fixation strategies, and the importance of accounting for potential alignment changes. CONCLUSION: The effective management of occipital bone erosion after posterior cervical spine surgery for destructive spondyloarthropathy necessitates meticulous fixation planning, proactive rod length adjustment, preoperative assessment of the occipital position, and consideration of the compensatory upper cervical range of motion to prevent migration-related issues.

Serum periostin levels correlate with severity of intervertebral disc degeneration.

PURPOSE: Periostin, an extracellular matrix protein closely related to mechanical stress, inflammation, and ageing, has been implicated in intervertebral disc degeneration (IVDD) in basic research. However, it has not been examined in clinical cases. This study aimed to evaluate the association between IVDD severity and serum periostin concentration as well as to analyse potential associations between IVDD and clinical and demographic factors. METHODS: This retrospective cohort study included 198 patients who underwent lumbar disc herniation and lumbar canal stenosis between January 2020 and December 2022. The severity of IVDD was evaluated using the Pfirrmann grading, whereas serum periostin levels were measured using ELISA kits. Clinical demographics, including age, sex, body mass index, comorbidities, psoas muscle index, and spinal disease, were also recorded. RESULTS: This study demonstrated a significant correlation between high serum periostin levels and IVDD severity, as indicated by a high cumulative Pfirrmann score. Serum periostin levels were identified as an independent risk factor for IVDD in a multivariate regression model. Correlation analysis showed a correlation between periostin levels and Pfirrmann grade at each lumbar level (ρ = 0.458-0.550, p < 0.001) and a strong correlation with cumulative Pfirrmann score (ρ = 0.690, p < 0.001). CONCLUSION: The higher the serum periostin level, the higher the cumulative Pfirrmann score. Multivariate analysis showed that serum periostin was an independent risk factor for IVDD. Periostin levels may be a clinically suitable and useful biomarker for diagnosing IVDD, estimating disease progression and activity, providing prognostic information, and evaluating treatment options.

Gender Diversity of the Japanese Society for Spine Surgery and Related Research Annual Meetings from 2013 to 2022.

Introduction: There are no reports that have examined the annual trends of the percentage of women who are members of the Japanese Society for Spine Surgery and Related Research (JSSR) or their roles at annual meetings. Furthermore, the status of gender diversity in the JSSR remains unclear. This study aims to identify gender diversity in the JSSR by quantifying the role of women at annual meetings over the past decade. Methods: We performed a retrospective review to explore gender role in the JSSR annual meeting by examining the meeting programs for 2013-2022. The gender ratios were surveyed each year for the following: (1) first authors of general application abstracts (oral and poster), (2) meeting guest speakers, (3) meeting moderators, and (4) program editors of the abstracts. We also investigated the availability of gender equality symposiums. Results: The percentage of women applying (1.1%-2.1%) and those who were invited as participants [guest speaker (0%-0.9%), moderator (0%-5.8%), and program editor (0%-0.6%)] at the annual JSSR meetings was low, with no significant increase over the past decade. In addition, there has never been a symposium promoting gender equality at the annual JSSR meeting. Conclusions: Our findings suggest that a strong and active role for institutional leaders and senior members to support the scholarly activities of women spine surgeons is important for adopting gender diversity in the JSSR academia. The absence of gender equality symposiums and the few invited women participants at the JSSR annual meeting may be due to a lack of gender diversity awareness among conference organizers or unconscious gender bias. Monitoring the role of women in the JSSR annual meetings may solve the gender diversity problem.