Introduction: Increased signal intensity (ISI) on T2-weighted magnetic resonance imaging at the vertebral body level in cervical ossification of the posterior longitudinal ligament (OPLL) may reflect dynamic cord compression. This study investigated the prevalence, radiographic characteristics, and surgical outcomes associated with vertebral body-level ISI in patients with OPLL.

Methods: This retrospective study analyzed 95 patients with cervical OPLL who underwent surgery between 2013 and 2022. Patients were categorized on the basis of ISI location: group D (disc level, n=52) and group B (vertebral body level, n=23). Radiographic parameters including cervical alignment, range of motion (ROM), and K-line status were evaluated. Clinical outcomes were assessed using Japanese Orthopaedic Association (JOA) scores at 2-year follow-up.

Results: Vertebral body-level ISI was observed in 24.2% of the entire cohort, accounting for 30.7% of patients with ISI. Group B indicated significantly greater local ROM (10.3±2.2° vs 5.8±2.6°, p<0.0001) and more pronounced flexion kyphosis than did group D, and predominantly anterior cord compression compared with group D. In group B, fusion surgery yielded superior outcomes to decompression alone (JOA recovery rate: 59.9±21.7% vs 18.7±20.9%, p=0.0061), despite most patients being K-line (+).

Conclusions: Vertebral body-level ISI in cervical OPLL is associated with increased segmental mobility and flexion-related dynamic compression. These exploratory findings suggest that vertebral body-level ISI may warrant consideration of fusion surgery, even in K-line (+) cases. Prospective validation in larger cohorts is needed.

Background: Cervical ossification of the posterior longitudinal ligament (OPLL) often requires surgical decompression with fusion. Both anterior decompression and fusion (ADF) and posterior decompression and fusion (PDF) are used; however, comparative evidence regarding their clinical outcomes remains limited and inconsistent. This study aimed to systematically review and synthesize evidence comparing ADF and PDF in patients with cervical OPLL.

Methods: A systematic search of Embase, the Cochrane Library, and MEDLINE was conducted from database inception to November 30, 2024. Randomized controlled trials and cohort studies directly comparing ADF and PDF were included. Outcomes of interest included neurological recovery based on the Japanese Orthopaedic Association score or recovery rate, complication rates, radiographic parameters, pain, reoperation, patient-reported outcome measures (PROMs), and healthcare costs. Pooled analyses were performed using weighted mean differences or odds ratios with 95% confidence intervals. Certainty of evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation framework.

Results: Eleven studies met the inclusion criteria. The overall certainty of evidence was rated as very low. Pooled point estimates favored ADF for neurological recovery compared with PDF, although differences did not reach statistical significance. Similar findings were observed in subgroup analyses of patients with K-line (–) status or high canal-occupying ratios (≥50% to 60%). Perioperative complications were more frequent after ADF, whereas neurological complications occurred more often after PDF; however, neither comparison showed statistically significant differences. No significant differences were identified in pain reduction, radiographic outcomes, reoperation rates, or PROMs. One study reported higher healthcare costs in the PDF group. Substantial heterogeneity was present across most analyses.

Conclusions: Current evidence does not demonstrate a clear advantage of either anterior or posterior fusion strategies for cervical OPLL. Given the substantial heterogeneity and very low certainty of evidence, differences between approaches should be interpreted with caution. Further well-designed comparative studies are required to determine the optimal fusion strategy.

Background: Two-stage, anterior and posterior, cervical spine surgery is often utilized for complex spinal pathologies. The second stage may be performed on the same day or delayed to a separate day. A variety of considerations influence this decision, yet comprehensive and broad analyses examining predictors and outcomes of same-day versus delayed staging remain limited.

Methods: A retrospective cohort study was conducted to investigate the effects of same-day versus delayed staging on complications and surgical outcomes. Adults undergoing two-stage cervical procedures were identified using the Quality Outcomes Database. The primary exposure was delaying the second-stage surgery to a separate day, termed the delayed second stage. Demographic, clinical, and preoperative data were analyzed. Outcomes included patient-reported outcome measures (PROMs) and reoperation rates at 3, 12, and 24 months, as well as the 30-day complication rate.

Results: Among 394 patients (mean age 60.8±10.7, 52.0% male), 27.9% had delayed second-stage surgery, the majority had an anterior approach as the first stage (87.8%), and patients who had delayed second-stage surgery were less likely to have American Society of Anesthesiologists scores ≥3 (43.6% vs. 64.5%, p<0.001). Patients with delayed second-stage surgery had longer operative times (326±37.0 vs. 293±34.0 minutes, p=0.022) and longer hospital stays (4.4±0.79 vs. 3.1±0.54 days, p<0.001), with no significant differences in blood loss, reoperation rates, PROMs at 3, 12, and 24 months, or 30-day complication rates (all p>0.05).

Conclusions: These results suggest that delaying the second stage may be more a question of resource utilization rather than concern for a negative impact on patient outcomes. Surgeons should acknowledge that either staging strategy, same-day or delayed, results in equivalent clinical outcomes with some differences in perioperative outcomes. The choice to delay second-stage surgery should be patient-centered and consider institutional factors.

Introduction: Cervicobrachial symptoms are common causes of disability worldwide, yet the cost-effectiveness of combination therapy versus monotherapy remains unclear. In this nationwide multicenter study, we aimed to compare the economic value of multiple-drug therapy with that of monotherapy for cervicobrachial symptoms.

Methods: This prospective observational study, conducted through the Japanese Society for Spine Surgery and Related Research, included 261 adults with cervicobrachial symptoms across 28 institutions (July 2020 to July 2022). Patients received monotherapy (n=112) or multiple-drug therapy (n=149) using five pre-specified agents: loxoprofen, celecoxib, acetaminophen, tramadol-acetaminophen, and pregabalin. The primary outcome was quality-adjusted life years (QALYs), calculated from monthly EuroQol 5-Dimension 5-Level assessments over six months. The secondary outcomes were drug costs and incremental cost-effectiveness ratios (ICERs), evaluated against Japan's reference threshold of 5,000,000 JPY per QALY.

Results: Mean QALY gains were similar between the monotherapy (0.00267±0.00544) and multiple-drug therapy (0.00284±0.00774) groups, with no statistically significant difference (p>0.05). However, total drug costs were substantially higher with multiple-drug therapy (19,243 JPY vs. 8,275 JPY). ICERs were more favorable for monotherapy (3,093,957 JPY/QALY) than for multiple-drug therapy (6,781,101 JPY/QALY). Among agents used as monotherapy, loxoprofen (744,409 JPY/QALY) and acetaminophen (781,293 JPY/QALY) showed the most favorable cost-effectiveness profiles, whereas tramadol-acetaminophen (6,370,451 JPY/QALY) and pregabalin (10,995,651 JPY/QALY) had the least favorable cost-effectiveness. Most QALY gains occurred during the first three months in both groups.

Conclusions: Multiple-drug therapy approximately doubled pharmaceutical costs without providing additional QALY gains over six months. Monotherapy, particularly with non-steroidal anti-inflammatory drugs or acetaminophen, offers superior cost-effectiveness and should be prioritized as first-line treatment. These findings underscore the need for restraint in polypharmacy and provide real-world evidence to guide clinical decision-making and national healthcare policy.

Introduction: Transforaminal epidural injection (EI) is an effective treatment for lumbar disorders. We used a novel ultrasound (US)-guided approach to identify the lumbar transforaminal epidural space without radiation or electrical stimulation. This technique shows a characteristic "Lambda sign over Horizontal Line (LHL)" view focused on the pars interarticularis. Therefore, we aimed to determine the anatomical background of the intervertebral foramen and clinical outcomes of this technique.

Methods: In one cadaver, indigo carmine was injected into the sacral hiatus, and the L3 vertebra was removed with the L3/4 facet joint. The specimens were sectioned longitudinally along the L3 spinal nerve and examined using hematoxylin-eosin staining. For clinical analysis, 18 individuals with lower limb pain underwent our novel US-guided lumbar transforaminal EI. The Japanese Orthopedic Association Back Pain Evaluation Questionnaire (JOABPEQ) was assessed before and at one, two, and four weeks after the first intervention, and scores for three visual analog scales (VASs) and five domains were compared between baseline and 4 weeks. Additionally, patients were divided into two groups based on the number of injections (single-trial versus multiple-trial), and baseline demographic data were compared between them.

Results: Histological sections revealed oblique ligamentous tissue on the laterodorsal edge of the pars interarticularis, with the epidural space extending laterally. Among 15 complete follow-up cases, VAS scores for low back pain, lower limb pain, and all JOABPEQ domains except mental health improved significantly. Only the diagnosis differed significantly between the single-trial and multiple-trial groups.

Conclusions: Our novel US-guided transforaminal EI approach ("LHL") may improve pain and quality of life. However, multiple trials are required for cases of bony stenosis.

Introduction: Although follow-up is recommended for 2 years after lumbar spinal stenosis (LSS) surgery, some patients fail to complete all follow-up visits. In recent years, the treatment burden on older adults has attracted increasing attention, with particular emphasis on outpatient visits. Thus, we aimed to clarify the clinical characteristics of older adults who discontinued postoperative follow-up between 1 and 2 years after LSS surgery.

Methods: This retrospective study included consecutive patients aged ≥65 years who had undergone surgery for LSS at a single center between April 2020 and June 2023. At follow-up assessments scheduled 1 and 2 years after surgery, patients completed the Japanese Orthopaedic Association Back Pain Evaluation Questionnaire (JOABPEQ) and the Zurich Claudication Questionnaire (ZCQ). The preoperative and 1-year postoperative JOABPEQ and ZCQ scores were statistically compared between patients who did and did not complete follow-up and were adjusted using analysis of covariance or the Poisson regression model.

Results: Among the 330 patients who attended the 1-year follow-up visit, 252 (76.4%) attended the 2-year visit, whereas the remaining 78 (23.6%) did not. Patients who did not complete follow-up exhibited significantly higher rates of dyslipidemia (p=0.022), cardiovascular disease (p=0.005), and frailty (p=0.014), and a lower prevalence of spondylolisthesis (p<0.001) and fusion surgery (p<0.001), than those who completed the follow-up. Furthermore, patients who did not complete follow-up had worse scores in the psychological disorder domain of the JOABPEQ both preoperatively and at 1 year, and worse 1-year scores across all ZCQ domains than those who completed the follow-up.

Conclusions: Several factors were associated with the likelihood of discontinuing postoperative follow-up among older adults with LSS, and their postoperative outcomes were poorer. Therefore, when analyzing data from older adults with LSS at 2 years postoperatively, considering the characteristics of patients who discontinued follow-up is essential.

Background: The Global Alignment and Proportion score has been validated in surgical cohorts as a predictor of mechanical complications in adult spine deformity, but its significance in the general population is poorly understood. We examined the association of the Global Alignment and Proportion score categories with locomotor syndrome and health-related quality of life in community-dwelling middle-aged and older adults to clarify the role of proportionality of sagittal alignment in musculoskeletal function and quality of life.

Methods: Residents of Hokkaido, Japan, who underwent musculoskeletal health screening in 2019 were included in this retrospective cross-sectional study. Based on their Global Alignment and Proportion score classification, participants were divided into three groups: proportioned, moderately disproportioned (moderate), and severely disproportioned (severe). We compared participants' background, bone mineral density, exercise tests, pain levels, locomotor syndrome stage, and Short Form 36-Item Health Survey score data.

Results: The mean age of the 217 participants was 64.0±9.5 years; 127 were female. The mean Global Alignment and Proportion score was 6.1±3.4 points, and the proportioned, moderate, and severe groups comprised 27, 106, and 84 participants, respectively. A statistically significant trend was observed in which the number of participants at high risk for locomotive syndrome increased as the Global Alignment and Proportion risk state worsened. In the Short Form 36 Health Survey domains of bodily pain and physical component summary scores, statistically significant trends toward lower scores were observed across groups with worsening Global Alignment and Proportion risk status.

Conclusions: We identified an association between poorer Global Alignment and Proportion scores and the presence of locomotive syndrome, as well as lower health-related quality of life, among middle-aged and older adults. These findings suggest that the Global Alignment and Proportion score may be a useful indicator for characterizing musculoskeletal alignment in clinical and public health fields.

Introduction: Although fenestrated screws enhance pull-out strength, cement leakage into segmental veins carries a risk of pulmonary embolism. This study aimed to identify factors that contribute to cement leakage during posterior spinal fusion with fenestrated screws.

Methods: We conducted a retrospective analysis of 32 patients who underwent posterior spinal fusion with fenestrated pedicle screws. A total of 147 screws were evaluated using postoperative computed tomography (CT) scans. Risk factors were assessed by measuring vertebral CT values, the volume of injected cement and its ratio to vertebral body volume, and screw positioning parameters, including deviation and distance to the anterior and lateral walls.

Results: Cement leakage occurred in 75% of patients (24 of 32) and in 35% of screws (52 of 147). All leakages were classified as leakage into segmental veins. No symptomatic pulmonary embolism was observed. The thoracic spine exhibited a higher leakage rate than the lumbar spine (47.5% vs. 28.4%, p<0.05). Leakage was significantly associated with shorter distances from the screw tip to the anterior (5.1 mm vs. 7.8 mm) and lateral (4.8 mm vs. 7.3 mm) vertebral walls, as well as a higher cement-to-vertebral-volume ratio (7.1% vs. 4.7%, p<0.01). Leakage also correlated with higher CT values in the posterior vertebral region (126 Hounsfield Unit [HU] vs. 103 HU; p<0.05). Screw deviation showed no association.

Conclusions: Proximity of the screw tip to the anterior and lateral walls, as well as excessive cement injection relative to vertebral body size, significantly increases the risk of leakage. To mitigate this risk, screws should be placed centrally within the vertebral body and at a safe distance from the cortical boundaries. The amount of injected cement should also be determined according to the volume of the individual vertebral body. These findings provide practical guidance for safer screw placement in spinal fusion using fenestrated screws.

Introduction: Trisomy 18 is a chromosomal abnormality with an estimated prevalence of 4.8 per 10,000 births. The condition is associated with scoliosis; however, the nature of this relationship is incompletely understood, as historically the 1-year mortality rate has ranged from 75% to 95%. With modern treatment, many individuals with trisomy 18 are now surviving beyond their first year of life, and consequently treating teams are encountering a greater number of patients with trisomy 18-associated spinal deformity. This case series makes recommendations for the early identification of deformity in patients with trisomy 18.

Methods: The clinical records and spine or chest radiographs of 18 consecutive patients aged at least one year who were diagnosed with trisomy 18 were reviewed. The results of radiological assessment for the presence, prevalence, and time of onset of associated spinal deformity were described.

Results: Seventeen of 18 patients who survived beyond one year from birth demonstrated scoliosis. Eleven patients survived and seven died during follow-up. The average age at diagnosis was 2.1±1.5 years (range: 0.1-6.5), and the average age at final follow-up was 4.4±4.1 years (range: 1.1-19.1). The coronal angular deformity at final follow-up was 35.2°±30.4° (range: 14.0°-141.9°). Five patients were diagnosed with scoliosis before one year of age, two of whom had severe scoliosis greater than 45° at the time of diagnosis. Although one patient was treated with bracing, bracing failed to prevent progression of the coronal deformity. No patients underwent surgical correction due to poor health status.

Conclusions: Individuals with trisomy 18 develop scoliosis with very early onset. Screening for scoliosis from birth is recommended to facilitate early identification and characterization of spinal deformities in patients with trisomy 18.

Introduction: Caregiver satisfaction after neuromuscular scoliosis (NMS) surgery is generally high; however, the relationship between task-specific caregiving burden and global treatment satisfaction remains unclear. This study aimed to identify patient- and caregiver-related determinants of transfer difficulty and global satisfaction in the long-term postoperative period.

Methods: This cross-sectional follow-up study included individuals who underwent posterior spinal fusion for NMS between 2012 and 2020 and were ≥18 years at survey distribution. Caregivers completed a modified Bridwell questionnaire using 0-10 scales. Multivariate linear regression identified determinants of transfer difficulty and global satisfaction, with false discovery rate (FDR) correction applied.

Results: Sixty-two caregivers responded (63% response rate). In the patient-related model, higher adult body weight (β=−0.14, p_FDR=0.077) and greater residual Cobb angle (β=−0.082, p_FDR=0.065) showed trends in transfer difficulty scores, though neither reached the p_FDR<0.05 threshold. Among caregiver-reported domains, difficulty with changing clothes (β=0.75, p_FDR=0.081) demonstrated a similar trend. Global satisfaction was significantly associated with better respiratory status (β=0.36, p_FDR=0.023) and improved swallowing (β=−0.16, p_FDR=0.047). Transfer difficulty showed no association with global satisfaction (β=−0.007, p_FDR=0.90).

Conclusions: These findings represent exploratory associations observed at a single time point in adulthood and do not imply causal relationships. Transfer difficulty in adulthood appears to be primarily associated with body size and residual spinal deformity, whereas global satisfaction is primarily associated with improvements in respiratory and swallowing function. These findings indicate a dissociation between task-specific caregiving burden and global treatment satisfaction, suggesting that caregivers may affirm long-term treatment value despite ongoing physical challenges.

Introduction: The prone position is generally regarded as the standard posture for back extensor strength testing. However, some older adults may have difficulty assuming this position, making alternative approaches more clinically feasible. It remains unclear whether measurements obtained in the sitting and semi-standing positions demonstrate sufficient validity compared with those in the prone position. This study aimed to evaluate the reliability and validity of isometric back extensor strength measurements using hand-held dynamometry (HHD) in the sitting position and the Biodex system in the semi-standing position. The results were compared with measurements in the prone position.

Methods: Thirty-four healthy adults (10 males and 24 females; mean age, 23.8 years) participated. Back extensor strength was assessed using three methods: HHD in the prone, HHD in the sitting position, and the Biodex system in the semi-standing position. Test–retest reliability was evaluated using two sessions. Convergent validity of HHD in the sitting position and the Biodex in the semi-standing position was examined and compared with prone HHD, which served as a reference standard.

Results: The semi-standing Biodex demonstrated excellent reliability and sufficient convergent validity compared with prone HHD, whereas HHD in the sitting position showed acceptable reliability but limited validity. Intraclass correlation coefficients (ICCs) indicated excellent reliability for prone HHD (ICC=0.95) and semi-standing Biodex (ICC=0.92), while sitting HHD showed acceptable reliability (ICC=0.76). Regarding convergent validity, the Biodex in the semi-standing position showed a moderate correlation with prone HHD (r=0.60), whereas sitting HHD showed a weaker correlation (r=0.45).

Conclusions: The Biodex system in the semi-standing position demonstrated excellent reliability and sufficient validity for assessing back extensor strength. In contrast, HHD in the sitting position showed acceptable reliability but limited validity, which may be influenced by the measurement protocol used. Further studies are needed to improve measurement protocols, particularly for use in older adults and clinical populations.

Introduction: This study aimed to evaluate pain outcomes after Neurotropin initiation in individuals with chronic low back pain (CLBP) and to explore factors associated with treatment response.

Methods: This multicenter retrospective observational study included patients with CLBP (duration ≥3 months) who received oral Neurotropin therapy (4 tablets daily) from May 2024 to May 2025. The primary outcome was pain intensity, measured using a visual analog scale (VAS) at baseline and at 2, 4, 8, and 12 weeks. The secondary outcomes were patient characteristics, pain features, simplified Spine painDETECT questionnaire scores, and Brief Scale for Psychiatric Problems in Orthopaedic Patients (BS-POP) scores. Statistical analyses were conducted using paired t-tests with Bonferroni correction, repeated-measures analysis of variance, and multivariate regression.

Results: A total of 106 patients (46 males, 60 females; mean age: 66.5±15.8 years) were included. The baseline VAS score was 6.74±1.12. Neurotropin was associated with significant pain reduction over 12 weeks, with VAS scores decreasing to 5.40±1.42 at 2 weeks, 5.15±1.39 at 4 weeks, 4.95±1.38 at 8 weeks, and 4.73±1.48 at 12 weeks (p<0.01 for all). The mean VAS score improvement was 2.14 points (95% confidence interval: 1.76-2.52) at 12 weeks. The minimal clinically important difference (≥1.5 points) was achieved by 62.3% (66/106) of patients. A BS-POP score ≥11 (indicating psychiatric problems) was significantly associated with reduced treatment response (VAS score improvement: 1.45±1.22 vs. 2.38±1.18 points, p=0.001). Pain duration was negatively correlated with treatment response (r=-0.26, p=0.049). No adverse events were reported.

Conclusions: Neurotropin was associated with significant pain reduction in CLBP in this retrospective observational study, with an excellent safety profile. Psychiatric comorbidities and longer pain duration were associated with reduced treatment response. Neurotropin may be a beneficial therapeutic option for CLBP, particularly in patients considered unsuitable for long-term non-steroidal anti-inflammatory drug therapy, although these findings require confirmation in randomized controlled trials.

Introduction: Anterior sacroiliac joint (SIJ) fusion has been performed for severe SIJ disorders and has demonstrated stable long-term outcomes; however, its relatively high invasiveness remains a significant concern. To overcome this limitation, we developed a posterior fusion using transarticular cylindrical cages combined with posterior instrumentation. This study describes the posterior SIJ fusion technique and evaluates the surgical outcomes.

Technical Note: An S1 pedicle screw is inserted toward the sacral promontory, and two S2 alar-iliac screws are placed in the ilium. All three screws are connected to a rod. One or two cylindrical cages filled with cancellous bone are inserted into the SIJ via a trans-iliac bony channel lateral to the posterior superior iliac spine to promote fusion in the anterior-superior portion of the SIJ while preserving the posterior sacroiliac ligaments. Seventeen patients (20 joints) with SIJ disorders were followed for a mean period of 53±23 months. Bone union was obtained in 93.3% of joints. Postoperative SIJ pain evaluated by the visual analog scale significantly improved from 87±18 to 24±25 mm (p<0.0001), and activities of daily living, assessed by the Denver SIJ Questionnaire, improved from 32±11 to 18±16 (p=0.0002).

Conclusions: The posterior SIJ fusion technique using transarticular cylindrical cages via a trans-iliac bony channel combined with posterior instrumentation resulted in favorable postoperative outcomes in patients with SIJ disorders.