搜索结果：Journal of orthopaedic science : official journal of the Japanese Orthopaedic Association

The size and location of the glenoid defect have been extensively studied in patients with anterior shoulder instability. However, in patients with traumatic posterior instability, little is known regarding the location and size of the bony defect of the glenoid. The purpose of the present study was to clarify the location and extent of the glenoid defect in shoulders with traumatic posterior instability with use of CT images. Forty-three shoulders of 42 patients with traumatic posterior instability treated at 7 hospitals were included. Three-dimensional images of the glenoid reconstructed from computed tomography were assessed using image analysis software. The location and size of the glenoid defect were investigated and described on a clock face of the glenoid. Thirty-eight of 43 shoulders (88 %) had a glenoid bony defect. Eleven shoulders (26 %) had a bony fragment. The defect width of the glenoid was 2.5 ± 1.3 mm (mean ± standard deviation), which was equivalent to 9.1 ± 5.3 % of the glenoid width. The mean orientation of the defect was pointing toward 8:12, at a mean angle of 246° ± 13.2° from the 12-o'clock direction in the right shoulder. The glenoid defects were located between 5:37 and 10:38. The prevalence of the glenoid bony defect in patients with traumatic posterior shoulder instability was as high as that in patients with anterior shoulder instability. However, its size was smaller than the anterior instability and it was located posteroinferiorly. IRB APPROVAL: #2022-1-1168.

Arthroscopic techniques for the knee joint continue to evolve, driven by the global shift toward "save the meniscus" and refinement of anterior cruciate ligament reconstruction technique. The purpose of this study was to evaluate nationwide trends in meniscal surgery and anterior cruciate ligament reconstruction in Japan using three years of data from the Japan Sports Orthopaedic Association registry. This registry-based study analyzed arthroscopic knee procedures performed by Japan Sports Orthopaedic Association member surgeons between April 2021 and March 2024. Extracted data included isolated medial and lateral meniscus procedures, repair techniques, primary and revision anterior cruciate ligament reconstructions, graft selection, and concomitant meniscal treatments. There were 51,074, 52,681, and 54,841 arthroscopic knee surgeries in 2021, 2022, and 2023, respectively. Medial meniscal repair increased annually (37.6%-41.9%), and lateral meniscal repair exceeded resection across all years. Arthroscopic meniscus resection decreased both in medial and lateral meniscus resections over time. The all-inside with anchor device technique was common in medial (43.2%-49.9%) and lateral (37.3%-48.9%) meniscus repairs. The inside-out, outside-in, intra-articular all-inside, and pull-out techniques were also frequently performed. Primary anterior cruciate ligament reconstructions increased from 12,114 to 13,500 cases, with hamstring autografts predominant (>80%), but decreased slightly over time. Quadriceps tendon autografts increased from 1.5% to 3.8%. The number of revision anterior cruciate ligament reconstruction cases was 1,072, 1,669, and 1,084, respectively. Bone-patellar tendon-bone autografts were the most commonly (∼60%) used for revision anterior cruciate ligament reconstructions. Hamstring autografts decreased from 33.6% to 28.4%, with quadriceps tendon graft use increasing from 8.3% to 11.6%. This study provides the first nationwide analysis of arthroscopic knee surgery focusing on meniscus and anterior cruciate ligament procedures in Japan, demonstrating increasing adoption of meniscal repair and changing graft selection patterns in anterior cruciate ligament reconstruction.

This study aimed to determine whether the association of knee extensor strength symmetry and psychological factors with single-leg hop distance (SLHD) differs according to recovery of knee extensor strength after anterior cruciate ligament (ACL) reconstruction with hamstring autograft. Patients who underwent primary ACL reconstruction with knee function test results at 12 months after the surgery were included. Isokinetic knee extensor strength and SLHD were assessed, and the limb symmetry index (LSI) were calculated. Tampa scale for kinesiophobia-11 (TSK-11) score and ACL-Return to Sport after Injury (ACL-RSI) score were measured as psychological factors. The patients were divided into two groups according to the LSI of knee extensor strength: at least 80 % (the High group) or less than 80 % (the Low group). Multivariable liner regression analyses were conducted with the LSI of the SLHD as dependent variable, and the LSI of knee extensor strength and the psychological factors as independent variables for the High and Low groups, respectively. Of the 251 patients, 163 patients were included in the High group, and 88 patients were included in the Low group. In the High group, the psychological factors were significantly associated with the SLHD, whereas the LSI of knee extensor strength was not associated. Conversely, in the Low group, the LSI of knee extensor strength was significantly associated with SLHD, whereas the psychological factors were not associated. The association of knee extensor strength symmetry and psychological factors with SLHD differs according to knee extensor strength recovery after ACL reconstruction.

Sarcomas of bone requiring an intercalary resection of femur are rare and challenging. In the absence of set guidelines, they are variously managed with intercalary prosthesis, cement spacers, allografts, recycled tumor bone, and autografts. We have used recycled tumor bone and/or vascularised fibula over the years for such resections. In this first-of-its-kind study on Indian patients, we aim to analyse the outcome of these procedures in femur. Twenty six patients undergoing an intercalary resection of femur from 2011 to 2024 by a single surgeon were analysed, of which one was excluded. All the patients underwent intercalary resection and reconstruction using recycled tumor and/or vascularised fibula. The demographic and surgical details, time to union, functional outcome and complications were analysed. 21 patients were treated with reimplantation of recycled tumor bone (extracorporeal radiation therapy (ECRT) in 15 and cryotherapy in 6). A vascularised fibula graft was used in 17 patients; as a stand-alone graft in 4 and in combination with recycled tumor bone in 13. After a mean follow up of 61.3 months (3-144 months), all patients showed union. Addition of a vascularised fibula graft to recycled tumor bone reduced the time to union (p = 0.02) without increasing the risk of a complication. Additionally, patients undergoing cryotherapy had shorter time to union (6.83 months) when compared to those who underwent ECRT (14.43 months), with fewer complications. (P = 0.02). Use of a vascularised fibula as a stand-alone graft took the maximum time to union. Resection length did not correlate with complication rates and functional outcome. Biological reconstruction after an intercalary resection of femur gives excellent long term results, with acceptable complication rates. We recommend the addition of a vascularised fibula graft to recycled tumor bone for intercalary resections of femur. Pedicled cryotherapy for recycling of tumor bone, when feasible, leads to fastest rehabilitation to optimal function.

The survivors from crush syndrome are often disabled due to the affected limbs, with excessive fibrosis changes at damaged muscle tissue. We previously reported that a zinc chelator (N,N,N',N'-tetrakis-(2-pyridylmethyl)-ethylenediamine: TPEN) administration to the crush syndrome mice model inhibited neutrophil activation induced by ischemia-reperfusion, alleviating the inflammatory response. In the present study, we investigated the effects of TPEN administration on fibrosis in affected limb muscles. Eight-week-old C57BL/6J mice were subjected to bilateral hindlimb compression using a rubber tourniquet for 2 h to create a crush syndrome model. Compression was then released to allow reperfusion. Gait evaluations and muscle tissue analyses were performed up to 4 weeks post-reperfusion. We investigated the effects of TPEN administration on functional recovery and histopathology of the affected muscles. In the chronic phase of the crush syndrome model, the gait function was impaired owing to muscle tissue fibrosis. The affected muscle tissue sustained sarcolemma hyperpermeability caused by basement membrane disruption and mitochondrial fission, resulting from elevated neutrophil elastase expression. In muscle tissue, PECAM-1-positive vascular endothelial cells co-expressed Notch1 and αSMA, indicating induction of endothelial-to-mesenchymal transition (EndMT) was occurring following persistent mitochondrial fission. TPEN administration reduced neutrophil elastase expression, improving the sarcolemma integrity due to the reduced infiltration of neutrophils. This led to the inhibition of EndMT, which minimized fibrosis and accelerated muscle regeneration, allowing for better functional recovery. This study demonstrates that zinc chelator administration not only alleviates fibrosis in muscle tissues damaged by crush syndrome but also stimulates tissue regeneration in the chronic phase. Our findings provide insight into the mechanism of muscle fibrosis and may represent a breakthrough in the treatment of crush syndrome, potentially minimizing long-term disability in the affected limbs.

In pectoralis minor muscle (PMiM) transfer, the PMiM tendon is typically harvested with a bone chip using a chisel from the medial surface of the coracoid process, as it is primarily composed of muscle tissue. However, variations in the insertion patterns and attachment sites of the PMiM tendon on the coracoid process have been reported, which may affect surgical techniques. This study aimed to investigate the anatomical variations in the attachment site of the PMiM tendon to the coracoid process using cadaveric shoulders. The attachment site of the PMiM tendon to the coracoid process was examined in 22 cadaver shoulders. The coracoid length and width were also measured as indicators of body size. In 11 of the 22 shoulders, the PMiM tendon was attached to the medial surface of the coracoid process. In the remaining 11 shoulders, the tendon was attached to either the superior or medial-to-superior surface, with the tendon extending toward the glenohumeral joint. The mean coracoid length and width were 42.1 &#xb1; 4.2 mm and 17.1 &#xb1; 2.1 mm, respectively, and both measurements were significantly greater in shoulders with medial surface attachments (P < 0.05). The PMiM tendon was attached to the medial surface of the coracoid process in 50 % of the examined shoulders. Shoulders with medial surface attachments exhibited significantly greater coracoid lengths compared with those with superior or medial-to-superior attachments. These anatomical insights may assist in reducing the risk of damaging the muscle-bone junction during PMiM tendon harvesting for surgical transfer.

Hallux valgus, a common deformity of the forefoot, is characterized by lateral deviation of the hallux at the metatarsophalangeal joint, often requiring surgery. Juvenile hallux valgus, defined by its development during childhood or adolescence, has a high postoperative recurrence rate. However, its etiology remains unclear. Several studies have found that the radius of curvature of the first metatarsal head is smaller in individuals with adult hallux valgus than in healthy controls, possibly contributing to progression of deformity or recurrence. However, to our knowledge, no detailed morphological analysis focused on juvenile hallux valgus has been published. In the present study, we aimed to characterize juvenile hallux valgus morphology, emphasizing radius of curvature. The cohort of this retrospective, single-center study comprised patients aged &#x2264;20 years who were allocated to juvenile hallux valgus (53 feet, 32 patients) and typically developing group (56 feet, 56 patients). An adult hallux valgus group (102 feet, 63 patients) was also analyzed. Both juvenile and adult hallux valgus were defined by a hallux valgus angle &#x2265;20&#xb0;. Radius of curvature was measured on weight-bearing radiographs using ImageJ software and normalized by metatarsal length. Additional parameters investigated included hallux valgus angle, M1-M2A, M1-M5A, distal metatarsal articular angle, sesamoid position, round sign, 1:2 metatarsal ratio, epiphyseal line status, cuneiform obliquity, calcaneal pitch, and Meary's angle. Radius of curvature was significantly smaller in the juvenile hallux valgus group than in both typically developing and adult hallux valgus groups (p < 0.001). Logistic regression identified radius of curvature (p = 0.02), distal metatarsal articular angle (p = 0.002), and female sex (p = 0.002) as independent predictors of juvenile hallux valgus. A smaller first metatarsal head radius of curvature may contribute to metatarsophalangeal joint instability and the pathogenesis of juvenile hallux valgus. Level III, comparative study.

Primary spine tumors are rare but can cause pain and neurological symptoms, occasionally requiring surgery. Previous national database studies have primarily focused on malignant spine tumors; however, data on primary intermediate spine tumors (PISTs) and primary benign spine tumors (PBSTs) remain limited. Therefore, we aimed to describe the demographic, clinical, and surgical characteristics of PISTs and PBSTs using the Bone and Soft Tissue Tumor (BSTT) Registry of the Japanese Orthopaedic Association. We analyzed 908 cases of PISTs (n = 118) and PBSTs (n = 790) from the BSTT Registry (2006-2019). We evaluated and stratified the clinical, anatomical, and histological characteristics according to tumor grade, patient age, tumor location, and histological subtype. Surgical data were evaluated using procedure and margin status. Hemangiomas were the most common tumors (48.2 %), followed by giant cell tumor of bone (9.5 %) and Langerhans cell histiocytosis (7.0 %). PISTs were significantly more common in younger patients (p < 0.001), whereas PBSTs showed a bimodal age distribution. The lumbar spine was the most frequently affected site, with no significant difference between patients with PISTs and those with PBSTs (p = 0.521). Imaging-based diagnoses were frequent in patients with PBSTs (p < 0.001). Surgery was performed in 23.2 % of all cases and 63.6 % of patients with PISTs (p < 0.001). Resection was the most common procedure (63.5 %), and intralesional margins predominated (49.3 %), with margin status significantly differing according to tumor grade (p = 0.042). This nationwide registry study provides the largest dataset of PISTs and PBSTs to date, including 908 cases and 22 histological subtypes. Our findings highlight age- and location-specific tumor trends and offer valuable insights into real-world diagnostic and surgical practices. These results support future research and demonstrate the value of large-scale registry data for rare spinal tumors.

In Japan, secondary screening for developmental hip dysplasia has expanded. However, the capacity of screening programs has outpaced the availability of ultrasonography and the number of clinicians who perform and interpret examinations outside tertiary centers. Plain radiography is widely accessible; however, interpreting images in infants can be challenging. This study developed and validated a deep learning-based system to support radiographic diagnosis and test a prespecified two-step triage strategy for clinical use. Overall, 1188 anteroposterior pelvic radiographs of infants aged 2-12 months were retrospectively analyzed. Three non-overlapping test subsets (50 images each) represented routine screening, images without a visible femoral-head ossification center, and images from external hospitals; the remainder were used for training and internal validation. The system generates measurements and the International Hip Dysplasia Institute grades for each radiograph. All test images were independently graded by two pediatric orthopedic surgeons, and the consensus served as a categorical reference. The agreement was summarized using the intraclass correlation coefficient for measurements and quadratic-weighted kappa for grades. The triage strategy was as follows: (1) no further imaging or referral when both hips were grade 1, and (2) high-priority alert when either hip was grade &#x2265;2 and/or the acetabular angle was at least 25&#xb0;. Agreement for the principal measurement between the system and each reader was 0.83-0.84 by intraclass correlation, comparable to inter-reader agreement (0.81), with small biases and acceptable limits of agreement. For grades, quadratic-weighted kappa was 0.63-0.75 across subsets, with disagreements mainly between adjacent categories. With a 25-degree cutoff, the triage strategy achieved sensitivities of 0.75-0.93 and specificities of 0.62-0.95 across subsets. The system supported radiographic screening decisions across diverse images typical of this age range, achieving comparable agreement with clinicians. Therefore, a prospective multicenter evaluation with thresholds adjusted for age and location is required.

Rapid identification of the causative microorganisms of osteoarticular infections is essential for successful treatment. BIOFIRE&#xae; FilmArray&#xae; Joint Infection Panel (JI panel), a fully automated multiplex PCR panel, can rapidly detect pathogens and antimicrobial resistance genes in the synovial joints in patients with acute osteoarticular infections. Accordingly, this study aimed to evaluate the diagnostic method of the JI panel in patients with osteoarticular infections. Synovial fluid samples were collected from patients with suspected osteoarticular infections. Fifty-five samples from 49 patients were analysed. The JI panel results were compared with those obtained using conventional culture methods. The sensitivities of the JI panel and culture for detecting microorganisms were 55 and 61 %, respectively, while the specificities were both 100 %. For patients with osteoarticular infections (n = 23) and positive culture or JI panel, the agreement rate between the JI panel and culture was 65 %. In five samples (22 %), the culture was positive, but the JI panel was negative. In three of the five JI panel-negative specimens (13 %), the bacteria identified in the culture were not included in the panel design. Three culture-negative specimens were JI panel-positive. Significantly higher sensitivity (70 % vs. 55 %; P = 0.008) was observed with the combined JI panel and culture than with the JI panel alone. The JI panel is a useful technique to identify causative bacteria rapidly and automatically, but the combination of the JI panel and culture methods is recommended because some pathogens are not included in the JI panel. Diagnostic level III.

Spontaneous posterior interosseous nerve (PIN) palsy is a rare condition with controversial clinical features. Although this palsy is conventionally treated conservatively, interfascicular neurolysis to release hourglass-like fascicular constrictions has also been recommended. This study aimed to clarify the clinical characteristics and treatment guidelines for this palsy. Fifty-eight limbs with spontaneous PIN palsy receiving conservative treatment or interfascicular neurolysis. The presence of pain as a premonitory symptom and the degree of muscle weakness were investigated. Patients were followed periodically from 3 months after palsy onset to either recovery or &#x2265;36 months afterwards. Limbs recovering to manual muscle testing (MMT) grade 4 or better for both the extensor pollicis longus and extensor digitorum were rated as Good recovery, with all others judged as Poor. Good recovery was achieved in 31 of 34 limbs treated conservatively and 19 of 24 of limbs by interfascicular neurolysis. Younger age at onset was the factor significantly associated with achieving Good recovery in 58 limbs treated by conservatively or interfascicular neurolysis. In the 24 limbs treated by interfascicular neurolysis, early timing of surgery was the factor significantly associated with attaining Good recovery. All 27 limbs with conservative treatment displaying &#x2265;1 grade of MMT improvement within 6 months after onset achieved Good recovery. In the 23 limbs with Poor recovery at 6 months by conservative treatment, Good recovery was attained in 4 of 7 limbs by continuing conservative treatment and in 12 of 16 limbs by subsequent interfascicular neurolysis. Although the latter treatment tended to produce better results, no significant difference was detected. Diverse clinical characteristics of spontaneous PIN palsy are useful for diagnosis. Conservative treatment is advisable within 6 months after onset of palsy. If no improvement is observed, interfascicular neurolysis without delay is a reasonable option.

The prevalence of central neuropathic pain (cNeuP) is increasing, particularly in older patients with spinal cord injury (SCI) without radiographic abnormalities resulting from minor external forces. Preclinical research has shown the effectiveness of gabapentinoid treatment for cNeuP after SCI in the spinal cord without stenosis. However, no studies have reported the efficacy of this treatment in models of spinal cord compressive lesions. To determine the effects of mirogabalin for cNeuP after SCI in a rat model of chronic spinal cord compressive lesions. A model of chronic spinal compressive lesion was created in rats by inserting an expandable water-absorbing polyurethane sheet under the sublaminar space. After 8 weeks, SCI without radiographic abnormalities causing hypersensitivity was induced using an Infinite Horizon Impactor device. The rats with cNeuP were divided into 3 groups: a saline group, a high-dose mirogabalin besylate (MGB) group, and an MGB low-dose group. Pain-related behavior and histology were evaluated for up to post operative 28 days. Compared with rats in the saline-treated group, those in the MGB-treated groups presented an increased pain threshold. Significant improvement was observed in MGB-treated rats for up to 21 days. Histology and mRNA expression revealed reduced expression of Iba-1 and &#x3b1;2&#x3b4;-1 in MGB-treated rats. Administration of MGB decreased Iba-1 and &#x3b1;2&#x3b4;-1 immunoreactivity in the dorsal horns of a rat model of cervical SCI at 4 weeks after injury. The inhibitory effect of MGB on the &#x3b1;2&#x3b4;-1 subunit after SCI may contribute to the analgesic effect on cNeuP.

To investigate the effectiveness of the Modified Kappa-line (mKappa-line) and Modified K-line (mK-line) as prognostic tools in managing ossification of the posterior longitudinal ligament (OPLL)-induced cervical myelopathy, especially in selective laminoplasty (LMP) cases. This retrospective study analyzed 78 patients who underwent LMP for OPLL-induced cervical myelopathy between September 2012 and April 2017. Patients were categorized based on their mKappa-line and mK-line statuses. Radiographic measurements, Japanese Orthopaedic Association (JOA) scores, and Neck Disability Index (NDI) were comprehensively analyzed. Patients in the mKappa-line (-) group exhibited significantly higher OPLL thickness (6.4 &#xb1; 1.7 mm; P < 0.01) and canal occupying ratio (64.4 %; P < 0.01) compared to the mKappa-line (+) group. The mKappa-line (-) group also reported lower postoperative JOA scores at 6 months (11.2 &#xb1; 4.1 vs. 14.5 &#xb1; 2.5; P = 0.01) and at the final follow-up (11.3 &#xb1; 4.0 vs. 14.4 &#xb1; 2.5; P = 0.01). Multivariate analysis highlighted the interval (INT) of mKappa-line as the sole significant predictor of JOA recovery rate (P = 0.037). Receiver operating characteristic (ROC) curve analysis revealed an area under the curve (AUC) of 0.792 for the mKappa-line (P < 0.01) and 0.675 for the mK-line (P < 0.01), with a critical cut-off value of 1.88 mm for the mKappa-line (INT), below which an inferior outcome (JOA RR < 40 %) is associated. The mKappa-line serves as a superior prognostic tool compared to the mK-line, providing enhanced guidance for surgical planning in selective LMP cases. Further research is warranted to confirm these findings and assess their clinical implications.

Posterior decompression for cervical ossification of the posterior longitudinal ligament (OPLL) is commonly performed using laminoplasty (LAMP) or posterior decompression with fusion (PDF). However, the relative benefits and risks of these procedures remain uncertain. This study aimed to compare clinical and radiographic outcomes between LAMP and PDF using a systematic review and meta-analysis. A systematic search of PubMed, Embase, and the Cochrane Library was conducted to identify studies comparing LAMP and PDF for cervical OPLL. Extracted data included neurological function, Neck Disability Index (NDI), neck pain, postoperative complications, and sagittal alignment. Neurological improvement was assessed using the Japanese Orthopaedic Association (JOA) score and recovery rate, with subgroup analyses performed according to K-line status. Meta-analyses were conducted to compare outcomes between procedures. The certainty of evidence was evaluated using the GRADE approach. Seventeen studies were included. Overall neurological recovery was similar between LAMP and PDF. In subgroup analysis, PDF demonstrated significantly greater improvement in patients with K-line (-) OPLL. Neck Disability Index scores did not differ between procedures. Postoperative neck pain was more frequent after PDF, and complication rates were consistently higher with PDF. Sagittal alignment parameters, including C2-7 sagittal vertical axis and C2-7 cervical lordosis angle, were similar between the two procedures. Neurological improvement following posterior decompression for cervical OPLL was similar between LAMP and PDF overall. While PDF showed significantly greater improvement in patients with K-line (-) OPLL, it was associated with higher rates of postoperative neck pain and complications. These findings indicate that PDF was associated with greater neurological improvement in patients with K-line (-) OPLL; however, this finding should be interpreted with caution given the observational nature of the included studies and the very low certainty of evidence, and should be considered hypothesis-generating.

The incidence of cancer and related deaths has increased substantially, with bone commonly serving as a metastatic site. Metastatic spinal tumors severely impair quality of life and activities of daily living. Prognostic scoring systems such as the revised Tokuhashi and Tomita scores are widely used in surgical decision-making for these tumors. However, their accuracy for recent cancer cases is unclear due to advances in cancer therapy. This multicenter, prospective study by the Japan Association of Spine Surgeons with Ambition analyzed 413 surgical cases for metastatic spinal tumors from October 2018 to March 2021. Of these, 272 cases with complete data were included. The Kaplan-Meier method, log-rank test, and statistical analysis were used to assess the association between survival and prognostic scores. Both the revised Tokuhashi and Tomita scores significantly stratified patients by survival (P < 0.01). The revised Tokuhashi score accurately predicted survival in 60.3 % of patients, underestimated it in 33.1 %, and overestimated it in 6.6 %. Significant score differences were found among groups with different survival durations. However, differentiating between <6-month and 6-12-month survival periods was difficult. The revised Tokuhashi and Tomita scores remain valid tools for predicting prognosis in patients undergoing surgery for metastatic spinal tumors. Nonetheless, these systems tend to underestimate survival in recent cases, particularly in short-term prognoses. Updating the scoring criteria may be necessary to reflect advancements in cancer therapy and extended patient survival.

This study examined the effect of improvements in cervical extension function on quality of life (QOL) in patients with dropped head syndrome (DHS) using patient-reported quality of life (PRQOL). A total of 116 DHS patients were divided into three groups according to cervical extension function at the end of outpatient physical therapy: Non-improvement group (unable to sphinx prone position), Improvement group (able to sphinx prone position), and Marked-improvement group (able to sphinx prone position and all-fours position). Disease-specific QOL (DHS-QOL scale) and health-related QOL (EQ-5D-3L) were assessed both before and after physical therapy, and the PRQOL results were compared among groups. The Non-improvement group showed no significant changes in either scale. In contrast, the Improvement group demonstrated moderate gains in both DHS-QOL and EQ-5D-3L, while the Marked-improvement group showed the greatest improvements, with large effect sizes across both measures. These findings indicate that enhancement of cervical extension function was strongly associated with PRQOL improvement. Cervical extensor improvement in DHS patients contributes not only to physical function but also to patient-perceived QOL. Acquisition of cervical extension in the all-fours position may serve as a clinically meaningful goal for improving QOL in DHS patients.

Spinal instrumentation surgery has seen improvements in safety and invasiveness thanks to technological innovations such as navigation systems, robotics, and improved implants, and its indications have expanded. This, combined with an increase in patients from aging population, has led to a global rise in surgical cases, particularly in countries with aging societies. However, Japan previously lacked a nationwide registry, making it difficult to fully understand the epidemiological trends of these surgeries. To address this, the Japanese Society of Spinal Instrumentation (JSIS) developed the web-based, multi-institutional case registration database (JSIS-DB) in 2018. This study analyzed 32,656 confirmed cases registered in the first- and second-generation JSIS-DB between 2018 and 2022. Patient background, implants used, and complications were statistically compared across age groups and surgical procedures. Statistical analysis included Chi-square tests, Wilcoxon rank-sum tests, and logistic regression analysis were used for intergroup comparisons. Regional disparities were observed with a notable concentration of registered cases in metropolitan areas. Patient age showed a bimodal distribution peaking in the teens and seventies. Two-thirds of procedures used posterior approaches. Minimally invasive techniques were significantly more frequent in elderly patients. Revision surgeries showed higher complication rates and more frequent cases without implant use. Systemic and psychiatric complications significantly increased with age. The proportion of patients aged 90 or older undergoing surgery showed a significant annual increase of 0.13 % (p = 0.014). This study presents the first analysis of spinal instrumentation surgery in Japan using a nationwide registry. The results revealed that surgical procedures are being selected based on age and risk factors, ranging from children to the super-elderly. Moving forward, appropriate surgical selection and perioperative management in a super-aged society will become increasingly important. The JSIS-DB is expected to play a significant role as a foundation for future quality improvement and clinical research.

Mild cervical ossification of the posterior longitudinal ligament (OPLL) is often asymptomatic or minimally symptomatic; however, its impact on physical function remains unclear. Locomotive syndrome (LS), a condition involving a decline in mobility due to musculoskeletal disorders, may help predict early functional impairments beyond neurological deficits. This study aimed to assess the severity of LS in patients with mild OPLL using the locomotive syndrome risk test battery. This cross-sectional study included 37 patients with mild OPLL (Japanese Orthopaedic Association score &#x2267;16 points) and 73 propensity score-matched controls with no major comorbidities. All participants underwent three LS assessments: the stand-up test, two-step test, and 25-question Geriatric Locomotive Function Scale (GLFS-25). LS stages were defined according to the Japanese Orthopaedic Association criteria. Group comparisons were performed using Student's t-test and the Chi-Square test. The OPLL group demonstrated significantly lower two-step and stand-up test scores (P < 0.05) and higher GLFS-25 scores (P = 0.0102) than controls. A significantly higher proportion of the OPLL group was classified as having LS stage 2 (32.4 % vs. 15.1 %, P = 0.0017), indicating more advanced locomotor dysfunction. Patients with mild cervical OPLL and preserved neurological function exhibited greater LS severity and subjective disabilities. The GLFS-25 effectively captured functional and psychosocial burden not reflected in traditional neurological scores, suggesting the need for early screening and mindful diagnostic communication.

Hypertension is a common comorbidity among patients undergoing knee arthroplasty and has been associated with postoperative complications; however, its clinical impact in Japanese populations remains unclear. This study evaluated the association between hypertension and in-hospital complications following total knee arthroplasty (TKA) and unicompartmental knee arthroplasty (UKA). A retrospective cohort study was conducted using Japan's nationwide Diagnosis Procedure Combination database (April 2016-March 2023). Postoperative outcomes-including deep vein thrombosis (DVT), pulmonary embolism (PE), cerebrovascular events, surgical site infection, and periprosthetic fracture-were compared between hypertension and non-hypertension groups. Propensity score (PS) matching (1:1) was performed using demographic variables, comorbidities, anesthesia type, and surgical procedure. Multivariate logistic regression was used to identify independent predictors of DVT. Of 257,319 eligible patients, PS matching yielded 77,637 patients per group. Hypertension was associated with a significantly higher incidence of DVT after matching, with an absolute risk difference of 1.82 %. Although hypertension was also associated with an increased relative risk of surgical site infection, the absolute risk difference was modest (0.46 %). Logistic regression identified hypertension (Odds ratio: 1.24; 95 % CI: 1.20-1.29) as an independent risk factor for DVT. Hypertension was also associated with longer hospitalization and greater transfusion volume on the day of surgery. Sensitivity analyses confirmed these findings. Hypertension independently increased the risk of postoperative complications after knee arthroplasty, particularly DVT. Although hypertension increased the relative risk of surgical site infection, the absolute risk difference was modest. These findings highlight the importance of perioperative risk stratification and venous thromboembolism prevention in patients with hypertension.