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Introduction:To evaluate the differences in anterior spinal bridging and sagittal spinal parameters between patients with diffuse idiopathic skeletal hyperostosis (DISH) and ankylosing spondylitis (AS) using whole-spine computed tomography (CT).
Methods: This retrospective study included patients with DISH (n = 111) and AS (n = 27). The number of anterior spinal bridges and sagittal spinal parameters was evaluated. The sagittal vertical axis (SVA) evaluated by whole-spine CT was defined as sup-SVA. Patients were further evaluated by matching their age and sex.
Results:Anterior spinal bridging frequently occurred in the thoracic spine in DISH and AS. In AS, bridging occurred in the lumbar spine according to the number of anterior spinal bridges. Sup-SVA and T5-T12 thoracic kyphosis (TK) were significantly greater in AS, and lumbar lordosis (LL) was significantly smaller in AS. TK was greater according to the number of anterior spinal bridges in both DISH and AS. Sup-SVA in DISH was greater according to the number of anterior spinal bridges, especially in the thoracic spine, whereas it was greater according to the lumbar in AS. LL in AS was smaller according to the number of lumbar bridges. Sup-SVA in DISH correlated with TK, whereas it correlated with both TK and LL in AS.
Conclusions: In patients with AS, the spine tends to bridge from the lumbar to the thoracic spine, causing kyphosis in the thoracolumbar spine. In patients with DISH, the spine tends to bridge from the thoracic spine, causing kyphosis in the thoracic spine. Thus, sup-SVA is greater in AS than in DISH.
Background: Low back pain (LBP) is a leading cause of disability worldwide, particularly in aging populations. While the Oswestry Disability Index (ODI) is widely used to assess LBP-related disability, few studies have evaluated its long-term trajectory and predictive factors in general populations.
Methods: This 7-year longitudinal study included 553 community-dwelling adults (mean age 66.3 years) from the Wakayama Spine Study, a population-based sub-cohort of the Research on Osteoarthritis/Osteoporosis against Disability (ROAD) study. Participants completed whole-spine magnetic resonance imaging and responded to the ODI questionnaire at baseline and follow-up. Disability levels were classified as mild (0%-20%), moderate (21%-40%), or severe (41%-60%). Longitudinal transitions in disability categories were analyzed descriptively. Multiple linear regression was used to identify predictors of ODI deterioration.
Results: The mean ODI score significantly increased from 9.6 ± 11.5 at baseline to 12.2 ± 14.2 after 7 years (p < 0.001), although the change did not reach clinical significance. Among participants initially classified as mildly disabled (n = 468), 88.0% remained stable, while 12.0% worsened. Of those with moderate disability (n = 73), 35.6% improved, 44.0% remained unchanged, and 20.5% worsened. No participant with severe disability (n = 40) improved to mild. Female sex, older age, higher body mass index, and vertebral fractures (semiquantitative grade ≥2) were significant predictors of worsening disability (p < 0.05). Higher baseline ODI was inversely associated with deterioration.
Conclusions: In this population-based cohort, LBP-related disability modestly worsened over 7 years. Older adults, women, individuals with obesity, and those with vertebral fractures were at greatest risk. These findings support early intervention and screening strategies to prevent disability progression in at-risk populations.
Background:Surgical decompression is necessary for anterior paradiscal-type thoracic spine tuberculosis with a neurological deficit; nevertheless, if pedicle screw fixation is unsuccessful, laminectomy may result in pan-vertebral instability. No available studies compare traditional anterolateral decompression (ALD) with the convenient, less extensive technique of transpedicular decompression (TPD).
Methods: This randomized comparative study of 20 cases of thoracic spine tuberculosis (T2-T12) used a posterior midline surgical approach with pedicle screw instrumentation. Diseased pedicle removal by eggshell technique (TPD) was compared with decompression by removal of the posterior part of the rib, transverse process, pedicle, and posterolateral part of the diseased vertebral body (ALD).
Results:Both groups had similar lengths of skin incision, intraoperative blood loss, and blood transfusion, but the duration of surgery was significantly less (p -value 0.019) in the TPD (156.5 minutes) than in the ALD group (184.5 minutes). Additional hemi-laminotomy was needed in two cases of TP, in the absence of liquid pus. Both groups showed similar neurological recovery except for one case of multidrug resistance in the ALD group. Improvements in the modified Japanese Orthopedics Association score (p = 0.719); visual analog scale (p = 0.259) and Nurick scale (p = 0.387) had no statistical difference between the two groups. Mean kyphosis correction of 6.64⁰ and 6.45⁰ and mean loss of correction at 2-years were 4.74⁰ and 1.98⁰ in the TPD and ALD groups, respectively. Complications included one case of superficial and deep infection in each group.
Conclusions:Similar outcomes of both approaches. TPD is quicker but may need hemi-laminotomy in the absence of liquid pus. ALD enables thick organized pus removal without compromising lamina in paradiscal-tuberculosis.
Introduction: Endoscopic spine surgery (ESS) presents advantages over traditional microscopic techniques but faces limitations in terms of field of view and depth perception. Virtual reality (VR) devices offer solutions by integrating real-time digital images into the surgical field, enabling magnification and teleproctoring.
Methods:The study was conducted in two phases. In the first phase, 55 surgeons completed a pre-use questionnaire. In the second phase, 19 surgeons participated in cadaveric practical training using the device and completed a post-use survey. Data were analyzed using R software.
Results:Following device use, surgeon confidence in magnification increased significantly (from 21% to 57%), with improved perception of image quality. Acceptance of teleproctoring rose from 33% to 94.7%. The device was considered superior to the operating microscope in both image quality and ergonomics.
Conclusions:VR head-mounted devices enhance visualization in ESS, allow intraoperative access to imaging, and support remote guidance via teleproctoring. Their adoption may contribute to improved training, planning, and surgeon ergonomics. However, additional controlled studies are required to determine their effects on clinical outcomes and operative performance.
Introduction:This study aimed to identify the factors associated with the postoperative deterioration of sagittal balance after surgery for adult spinal deformity (ASD), focusing on preoperative alignment and pelvic incidence (PI).
Methods:We retrospectively reviewed the medical records of 87 patients who underwent corrective surgery for ASD (2017-2020). Sagittal balance was assessed using the sagittal balance classification (SBC). The patients were classified as balanced (maintained SBC grade 1 or 2) or imbalanced (deteriorated to grade 3). Radiographic parameters, clinical outcomes (Japanese Orthopedics Association scores and mechanical complications), and bone mineral density were analyzed.
Results:In 15 patients (17.2%), the sagittal balance deteriorated to grade 3 (imbalanced group). Factors significantly associated with postoperative deterioration of sagittal balance included preoperative grade 3 SBC (73.3% vs. 23.6%, p < 0.001), steroid use (26.7% vs. 2.8%, p < 0.01), pelvic fusion (80% vs. 51.4%, p = 0.049), higher preoperative PI, sacral slope, and sagittal vertical axis. At 2 years, the imbalanced group showed a significantly greater corrective loss of the lumbar spine. Receiver operating curve analysis identified preoperative PI ≥52.1° as predictive of postoperative imbalance (sensitivity 86.7%, specificity 66.7%). The clinical outcomes were similar, but the reoperation rates were higher in the imbalanced group (20.0% vs. 2.8%, p = 0.03).
Conclusions:High preoperative PI, severe sagittal imbalance, steroid use, and pelvic fusion were predictive of postoperative sagittal balance deterioration, underscoring the need for personalized preoperative planning.
Background:Cervical spinal cord injury (CSCI) without major bone injury is increasing among older adults, particularly in aging societies like Japan. The optimal treatment strategies remain unclear, with conservative therapy often preferred, especially for older patients. However, surgery is frequently necessary due to poor improvement or progression of paralysis during conservative treatment. This study investigated the characteristics and outcomes of older patients with CSCI without major bone injury who transitioned from conservative treatment to surgery.
Methods:This nationwide, retrospective study examined data from patients aged ≥65 years with CSCI without major bone injury. The patients were categorized into 3 groups: conservative treatment, planned surgery, and those who switched from conservative treatment to surgery. The study aimed to identify the risk factors for conservative therapy failure that necessitate surgical intervention and to compare the outcomes between patients who had planned surgery and those who required surgery after conservative management failed.
Results:Among 615 patients, 422 (68.6%) received conservative treatment, 193 (31.4%) had planned surgery, and 116 (18.9%) transitioned from conservative to surgical treatment. Transition to surgery was mainly due to poor improvement or progression of neurological deficits. Significant risk factors for transitioning to surgery included younger age, presence of ossification of the posterior longitudinal ligament, and spinal cord signal changes on magnetic resonance imaging. Comparative analysis showed no significant differences in neurological outcomes between patients who had surgery as planned and those who required surgery after failed conservative treatment.
Conclusions:A significant proportion of older patients with CSCI without major bone injury who were initially managed conservatively eventually required surgery due to insufficient neurological improvement. The outcomes of patients who transitioned to surgery were similar to those who had surgery as initially planned, indicating that careful monitoring of conservative treatment followed by surgery, if necessary, may be an effective approach.
Background:The prone transpsoas (PTP) approach is a novel, single-position lumbar fusion technique that enables lateral lumbar interbody fusion (LLIF) entirely in the prone position, allowing simultaneous access to both the anterior and posterior spinal columns. While it offers advantages such as achieving circumferential fusion without repositioning the patient, it also presents challenges, including hemodynamic shifts, pressure-related complications, and technical difficulties in navigating complex anatomical structures. This study describes anatomical shifts relative to the lumbar spine when transitioning from the supine to the prone position.
Methods:This retrospective review included patients who underwent posterior lumbar fusion between 2018 and 2024 and had both preoperative magnetic resonance imaging (MRI) and intraoperative prone computed tomography-guided imaging. Patients with deformity, infection, trauma, prior fusion, or malignancy were excluded. Anteroposterior (AP) and mediolateral (ML) distances (in mm) were measured on axial slices using reference lines aligned to vertebral endplates at each lumbar level. Measurements included AP and ML distances to the abdominal great vessels, psoas major, and intervertebral discs. Dependent samples t-tests and analysis of variance were used to assess anatomical shifts from supine to prone and to compare segmental differences.
Results:Among the 74 patients (47% female), the mean age was 62.7 ± 12.2 years, and the mean body mass index was 29.8 5.8 kg/m2. Significant AP translation was observed at L2-L3 and L3-L4 for the inferior vena cava (p < 0.001) and aorta (p < 0.01), and at L4-L5 for the common iliac arteries (p < 0.001) and right iliac vein (p < 0.05). Symmetric AP excursion of the psoas major muscle was noted at L2-L3 and L4-L5 in the prone position (p < 0.05). No significant differences in mean translation were found across lumbar levels.
Conclusions:Prone positioning induces measurable anterior translation of both the psoas major muscle and great vessels, potentially altering the operative corridor utilized in the PTP approach. These discrepancies between supine MRI and prone intraoperative anatomy emphasize the need to account for positional anatomical changes to minimize neurovascular risk during PTP LLIF.
Introduction: Awareness of the harmful effects of long-term low-dose radiation is increasing. There are few comprehensive reports that accurately evaluate the radiation exposure dose to spinal interventionalists during selective nerve root block (SNRB). The purpose of this study was to evaluate the radiation exposure doses from C-arm fluoroscopy to different body areas of the interventionalist and to assess the effectiveness of lead-equivalent protective gear in reducing radiation exposure during SNRB.
Methods: Seven fresh cadavers were irradiated for 1 and 3 minutes using C-arm fluoroscopy to stimulate the real clinical setting of SNRB. The X-ray source was positioned both under and over the table. Radiation exposure doses were measured using real-time dosimeters. Lead-equivalent protective gear was placed on each body part (crystalline lens, thyroid gland, chest, non-dominant hand, dominant hand, gonads, and foot).
Results:Scatter radiation exposure doses to the upper body of the interventionalist were much higher when the X-ray source was positioned over the table compared to when it was positioned under the table. Use of X-ray protective gear reduced radiation exposure to the interventionalist regardless of the X-ray source position. The direct radiation dose to the hand in the irradiated field was extremely high when the X-ray source was positioned over the table—approximately 85 times higher than when under the table. Notably, hand doses remained extremely high even when the interventionalist wore protective gloves, although X-ray-protective-gear reduced overall radiation exposure.
Conclusion:This is the first report to quantify both scattered and direct radiation doses to each body part, as well as the reduction effect of using X-ray protective gear, in detail using fresh cadavers instead of patients. Spinal interventionalists should preferentially use an under-table X-ray source during SNRB and should consistently wear adequate X-ray-protective gear to minimize occupational radiation exposure.
Introduction:Herniated lumbar intervertebral discs migrate into the rostral or caudal anterior epidural space (AES). Previous studies have reported varying frequencies of migration direction, and the factors influencing the migration direction include patient age, affected disc level, and AES structural differences. However, the relationship between AES volume and migration direction remains unclarified. The purpose of this study was to measure the AES volume using computed tomography (CT) imaging and investigate the factors affecting herniated nucleus pulposus (HNP) migration in the sagittal direction.
Methods:We reviewed 42 patients who were surgically treated for migrated lumbar intervertebral disc herniation between 2014 and 2023. The primary endpoint was the ratio of the AES volume between vertebrae adjacent to the herniated disc. The secondary endpoints were patient demographics, disc level, clinical symptoms, disc degeneration, and lumbar instability. AES volume was measured by calculating the area between the posterior vertebral wall concavity and a line connecting the posterior walls on CT images, with the total volume determined as the sum of the slice areas multiplied by the slice width.
Results:A total of 14 patients exhibited rostral HNP migration, while 28 exhibited caudal HNP migration. Rostral HNP migration was associated with a higher prevalence of double-root involvement (p < 0.05) and a greater superior/inferior ratio of the AES volume (p < 0.01). Multivariate analysis identified the AES volume superior/inferior ratio (odds ratio: 9.551) as a factor significantly associated with the direction of HNP migration.
Conclusions:The HNP tends to migrate toward the direction with a larger AES volume because the herniated material follows the path of least resistance. Clinical presentation of double-root symptoms was strongly indicative of rostral HNP migration.
Introduction: In dropped head syndrome (DHS), the factors contributing to the prognosis due to conservative treatment have been unclear. The purpose of this study was to investigate the effect of spinal malalignment due to pre-existing thoracolumbar vertebral fractures on the improvement rate of conservative treatment of DHS.
Methods: Overall, 90 patients with DHS who visited our hospital and underwent conservative treatment for 6 months were included in the study. Patients were divided into 2 groups, Group F with and Group N without thoracolumbar vertebral fracture, and their improvement rate and spinal parameters were compared and statistically examined.
Results:Group F had a significantly larger sagittal vertical axis (SVA) and pelvic incidence minus lumbar lordosis (PI-LL). Cervicothoracic spine alignment did not differ between Groups F and N. The improvement rate of Group F was significantly lower than that of Group N (Group F: 18.8%, Group N: 54.1%).
Conclusions: DHS with thoracolumbar vertebral fracture has significantly large SVA and PI-LL, which would be a poor prognostic factor of conservative treatment.
Introduction: Degenerative cervical spondylolisthesis is associated with aging, neck pain, and myelopathy. While anterior spondylolisthesis (AS) has been extensively studied in relation to cervical sagittal parameters, posterior spondylolisthesis (PS) remains poorly understood despite its potential to cause myelopathy. This study investigates the association between PS and cervical sagittal parameters to elucidate its pathophysiology.
Methods:This retrospective study included 169 patients who underwent cervical spine surgery to treat cervical myelopathy, classified into 3 groups: PS, AS, and a control group without spondylolisthesis. Variables assessed included age, sex, body mass index, smoking history, T1 slope, sagittal vertical axis C2-C7 (SVA C2-C7), C2-C7 angle, C2-C7 range of motion, C1-C2 angle, and cervical disk degeneration (summed Pfirrmann grades). Logistic regression analysis was conducted to identify factors significantly associated with PS, and comparisons were made between the PS and AS groups.
Results:Of the 169 participants, 58 had PS, 22 had AS, and 89 formed the control group. A T1 slope ≥29° was significantly associated with PS (odds ratio: 1.090, p = 0.005). PS was more common in younger men with mild disk degeneration, while AS was more frequent in older women with severe disk degeneration. Patients with PS exhibited larger C2-C7 angles and smaller SVA C2-C7 compared to those with AS. A high T1 slope appeared to induce a compensatory increase in the C2-C7 angle, generating posterior shear force that may have contributed to the development of PS.
Conclusions:A T1 slope of ≥29° was associated with PS. Our findings suggest that a compensatory mechanism related to a high T1 slope may play a role in the pathophysiology of PS, providing new insights into its development in cervical spinal disorders.
Background: Although spine surgery has a high number of patented technologies, there has been little prior application of bibliometric analyses to effectively evaluate the technological literature in the cervical spine field. The aim of this review is to summarize and identify current patent trends in technologies for the stabilization and surgical management of cervical spine pathologies.
Methods: Multiple databases were systematically queried using Lens.org to identify technology patents designed to stabilize or surgically manage cervical spine injury or disease. The patents were then ordered by forward citation count, and the top 50 unique patents were included and organized into five categories: fusion/stabilization/fixation devices, external brace/supporter devices, arthroplasty implants, surgical instruments, and spacer/expansion devices. Subsequent assessments included patent priority year, publication year, priority region, legal status, and rank.
Results: The search results on March 11, 2024, yielded 440 patents published between 1973 and 2014. Of the top 50 most-cited patents, fusion/stabilization/fixation devices were the most common (27), followed by external brace/support devices (18). Patents for fusion/stabilization/fixation devices were more recent, peaking in 2001. The most common patents in the first to third quintiles were for fusion/stabilization/fixation devices.
Conclusions: Most patents before 1995 were for cervical brace and supporter devices. Since the turn of the 21st century, patented surgical fusion/fixation/stabilization devices have markedly increased. Further analysis of trends in cervical spine device technology can assist in guiding future innovation efforts.
Introduction: Diffuse idiopathic skeletal hyperostosis (DISH) -related fractures have a high frequency of delayed diagnosis and paralysis even if caused by low-energy trauma, which makes diagnosing vertebral fractures (VFs) with DISH challenging. This study compared the clinical and radiologic features of VFs with DISH.
Methods: This study included 252 patients (70 men and 182 women; mean age standard deviation, 81.0 8.6 years) with VFs in this study. Patients were divided into two groups depending on DISH (group D) or not (group N). We measured the sex, age, body mass index, hemoglobin A1c, and bone mineral density. This study also measured the spinopelvic sagittal alignments, local angular motion, inflection point, number of VFs, intervertebral disk (IVD) injury, and signal changes on magnetic resonance image (MRI).
Results: The presence of DISH in VFs was identified in 104 patients (41.3%) (49/70 [70.0%] in men vs. 55/182 [30.2%] in women). Group D was related to male sex, older age, larger thoracic kyphosis, VF at lower lumbar lesion, number of VFs, IVD injury, inflection point at lower lumbar, local angular motion, diffuse low signals on T1 MRI, and high or diffuse low signals on T2 MRI on univariant analysis. Multiple logistic regression analysis showed that the predictive factors for DISH were male sex, angular motion, VF at lower lumbar lesion, IVD injury, inflection point at lower lumbar, and diffuse low signals on T1 MRI.
Conclusions: DISH was related to IVD injury, angular motion, and diffuse low signals on T1 MRI. In addition, VFs with DISH were more frequently found in men at the lower lumbar lesion than in women at thoracolumbar. When physicians detect these factors, attention should be given to VFs with DISH, and whole-spine computed tomography should be considered not to overlook the presence of DISH.
Background:Prolapsed lumbar intervertebral disc (IVD) is a prevalent spinal cause of low back pain associated with radicular pain. Platelet-rich plasma (PRP) has emerged as a potential alternative to epidural steroid injections. This review aimed to compare the efficacy of epidural PRP and epidural steroid injections in treating low back pain due to prolapsed lumbar IVD, assessed using a pain scale and Oswestry' s disability index (ODI).
Methods: A systematic search of 4 databases (PubMed, Scopus, ScienceDirect, and Cochrane Central Register of Controlled Trials) up to July 2024 for randomized controlled trials comparing epidural PRP with steroids. Risk of Bias 2 was used for bias assessment. Pain and ODI mean differences (MDs) were calculated using RevMan v5.4. Heterogeneity was measured using I2, with random or fixed effects applied accordingly. The combined outcome progression of pain and ODI scores were computed using STATA/MP 17.0 software.
Results: Three trials (n = 132) were included. At 1 month, epidural steroid injections showed lower pain scores than PRP (standard MD = 1.04, 95% confidence interval [CI]: 0.63-1.46, p< 0.00001, I2 = 0%). At 6 months, epidural PRP injection demonstrated greater pain relief (MD = −1.51, 95% CI: −1.98 to −1.05,p< 0.00001, I2 = 0%) and lower ODI (MD = −9.71, 95% CI: −16.63 to −2.78, p = 0.006, I2 = 75%). Epidural steroids showed significant worsening in pain score (1 vs 3 months, p = 0.001; 3 vs 6 months, p = 0.003).
Conclusions: Epidural PRP provides sustained and gradual improvement of pain and ODI for patients with prolapsed lumbar IVD over months of follow-up, while steroids provide initial relief at 1 month but are associated with worsening at later follow-ups.
Introduction:The geriatric nutritional risk index (GNRI) has emerged as a useful predictor of surgical risk and postoperative outcomes. This study aimed to explore the utility of GNRI as a semiquantitative tool for predicting systemic and local complications after multilevel thoracolumbar fusion surgery in older patients and to evaluate the broader implications of nutritional status on postoperative recovery and independence.
Methods:This multicenter study included 249 patients aged 65 years or older who underwent thoracolumbar fusion of at least four vertebrae. The nutrition-related risk grades were defined by the GNRI values, and the patients were divided into four groups: risk absent (GNRI > 98), low risk (GNRI 92 to ≤98), moderate risk (GNRI 82 to <92), and major risk (GNRI < 82). The occurrence of systemic complications, surgical site infection (SSI), length of stay in the hospital, place of discharge, and occurrence of proximal junctional kyphosis or failure (PJK/PJF) within 2 years after surgery were examined.
Results:The risk-absent group consisted of 165 patients, the low-risk group of 40, the moderate-risk group of 36, and the major-risk group of eight. The incidence of any systemic complications (p = 0.016), PJK/PJF (p < 0.001), and hospital stay (p = 0.028) significantly increased with worsening GNRI. Furthermore, the number of patients who were discharged home significantly decreased as GNRI worsened (p < 0.001). SSI occurred most frequently in the risk-absent group (4.2%).
Conclusions:The GNRI serves as a semiquantitative assessment tool that enables the identification of high-risk patients who may benefit from preoperative nutritional interventions.
Introduction: Low bone mineral density (BMD), a history of vertebral fractures (VFs), and steroid use are established risk factors for VFs. Additionally, age, nutritional status, muscle mass, and spinal sagittal alignment have been linked to osteoporosis and fractures. This study aims to investigate the risk factors contributing to new occurrences of VFs.
Methods: We included 597 patients with osteoporosis who visited our outpatient department and were available for follow-up 1 year after the visit. The following data were collected: age at examination, presence of secondary osteoporosis, body mass index, lumbar spine BMD, femoral neck BMD, number of VFs, grip strength, trunk muscle mass, controlling nutritional status (CONUT) score, sagittal vertical axis (SVA), pelvic tilt, pelvic incidence–lumbar lordosis, thoracic kyphosis on whole-spine standing radiography, and osteoporosis treatment status at baseline. Patients who had new VFs confirmed on whole-spine standing radiography at the 1-year follow-up visit were included in the group with new VF occurrence. We performed between-group comparisons of each parameter. Additionally, to identify risk factors for new VFs, we conducted a multivariate analysis using the presence of new VFs as the dependent variable.
Results: A total of 60 new VFs occurred during the 1-year period, representing 10.1% of the study population. When comparing the new VF incidence group with the non-incidence group, the CONUT score and SVA were significantly higher in the new VF incidence group. There were no significant differences between the 2 groups for the other variables. Multiple logistic regression analysis indicated that both a high CONUT score and SVA were independent risk factors for the occurrence of new VFs.
Conclusions: The 1-year incidence of new VFs was 10.1% among patients with osteoporosis, despite appropriate osteoporosis treatment. These patients also exhibited malnutrition and spinal sagittal malalignment at baseline. Our findings suggest that malnutrition and spinal sagittal malalignment may be independent risk factors for the occurrence of new VFs.
Introduction:We evaluated the effect of 3 high-angle cages on spinal alignment and clinical outcomes following posterior lumbar interbody fusion (PLIF).
Methods:A retrospective analysis was performed on 104 patients who underwent PLIF at the L4/5 level between January 2021 and August 2023. Patients were divided into 3 groups: 12° (L), 16° (M), and 22° (H) cage groups. Lumbar spine radiographs were taken preoperatively and one year postoperatively to assess slip rate (% slip), segmental lumbar lordosis (SLL), segmental intervertebral angle (SIA), lumbar lordosis (LL), pelvic incidence-LL, sagittal vertical axis (SVA), Japanese Orthopedic Association score, and lower back pain visual analog scale score. Bone union and cage subsidence rates were evaluated using computed tomography 6 months postoperatively. Statistical analyses were performed using either the Wilcoxon signed rank test, Kruskal–Wallis test, or z-test.
Results:Intragroup analysis showed significant improvements in local alignment, with notable SVA improvement in the H group. Intergroup comparisons revealed no significant differences in preoperative evaluation items. Postoperatively, the H group showed significantly greater improvements in SLL and SIA than the L group. Although no significant difference was observed in bone union, the cage subsidence rate was significantly higher in theH group than in other groups.
Conclusions:PLIF using high-angle cages (≥12°) significantly improved local alignment in all groups. The 22° cage showed greater improvements in SLL and SIA but a higher incidence of cage subsidence. No significant clinical differences were observed between groups. LL in the lower lumbar spine can be achieved relatively easily using a cage with a larger angle in PLIF. However, although a cage with a larger angle may be advantageous for lordosis formation, postoperative clinical outcomes do not differ; therefore, cage selection should consider the surgeon's skill and patient factors, such as the degree of preoperative lumbar disc degeneration, instability, and alignment.
Background:Symptomatic lumbar foraminal stenosis (LFS) occurs when the neuroforamen narrows, compressing the exiting spinal nerve, leading to symptoms such as radicular pain, paresthesias, and potentially weakness. Although cross-sectional imaging studies are used for diagnostic purposes, there is no clear consensus as to which grading system best evaluates LFS, predisposing to inconsistencies in care. This systematic review aimed to evaluate and compare existing published grading systems for LFS to identify (1) systems most used within the literature and (2) the most effective and reliable method for classifying anatomic severity and clinical symptom correlation.
Methods:This study is a systematic review following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, analyzing available literature on grading systems for LFS, level of evidence IV. A comprehensive search of PubMed, Embase, and Cochrane Trials was conducted from inception through July 2024. Eligible studies were evaluated for methods, bias, sample size, patient demographics, imaging modalities, and grading systems. Bias was assessed using the Methodological Index for Non-Randomized Studies. Data were synthesized narratively and descriptively.
Results:The review included 35 studies, most using magnetic resonance imaging (88.6%). Seven grading systems have been identified. The original Lee et al. grading system was the most frequently used LFS grading system (69%), followed by Wildermuth et al. (14.3%). Notably, artificial intelligence (AI) grading systems were included in two studies (5.7%). Findings regarding symptom correlation were mixed.
Conclusions:The Lee et al. grading system remains the most used grading system for LFS in the literature and is reliable. Several small studies found an association between the Lee et al. system and clinical symptoms/treatment outcomes; however, this was not universally found. Further investigation is needed to validate the newer grading. The introduction of AI may offer promise for refining the diagnostic and clinical utility of published LFS grading systems.
Introduction: Delayed diagnosis and therapy initiation for pyogenic spondylitis can have severe and fatal consequences. Early diagnosis and intervention are crucial in the treatment of pyogenic spondylitis. This multicenter cross-sectional study with prospective case series aimed to identify factors influencing the time from symptom onset to the diagnosis of pyogenic spondylitis.
Methods: Patients hospitalized with pyogenic spondylitis between 2019 and 2023 were included. Patients were classified into 2 groups: the delayed diagnosis group (>30 days from the onset of initial symptoms to the diagnosis of pyogenic spondylitis) and the early diagnosis group (within 29 days). Risk factors for delayed diagnosis were analyzed.
Results: A total of 74 patients (42 men and 32 women; mean age: 70.2 years) from 5 institutions were included. Univariate analysis of risk factors for delayed diagnosis revealed that the significant risk factors included advanced age (p = 0.03), low white blood cell count (p < 0.01), low C-reactive protein level (p < 0.05), and semi-rigid spinal level, based on the spinal instability neoplastic score classification (p = 0.05). Multivariate analysis for delayed diagnosis showed that the location at the semi-rigid spinal level was a significant risk factor (p = 0.02). The vertebral bone destruction rate and abscess cavity index in the delayed diagnosis group were significantly higher than those in the early diagnosis group (p < 0.01 and p < 0.01, respectively).
Conclusions: Significant risk factors for delayed diagnosis of pyogenic spondylodiscitis include infection at the semi-rigid thoracic spinal level. Early diagnosis of spondylodiscitis is crucial because delayed diagnosis can lead to progressive bone destruction and the formation of large abscesses. Increased awareness of thoracic spinal infections, which can easily delay diagnosis, could help in the early diagnosis and treatment of pyogenic spondylodiscitis.
Objectives:Total disc replacement (TDR) using Mobi-C® and Prestige LP® was approved in Japan in 2017. To ensure effective surgical outcomes with TDR, the Japanese TDR guideline was established before its clinical use, and a registry system was developed to monitor the safety of early cases in Japan. This study assessed complications associated with TDR during the early post-approval period using this nationwide registry to evaluate the short-term safety of single-level TDR.
Methods:Data from the nationwide registry covering postoperative 2-year surveillance were analyzed for single-level TDR performed during the post-marketing surveillance period in Japan. The database included patient characteristics, surgical details, complications, and reoperations. Complication and reoperation rates were analyzed for the perioperative period during hospitalization and the postoperative period after discharge.
Results:In total, 332 patients were enrolled in this study, and 271 patients completed the 2-year follow-up (81.6%). Mobi-C® and Prestige LP® were used in 158 and 113 patients, respectively. Perioperative complications included hematoma (n = 3) and airway obstruction (n = 1). Three (1.1%) patients with hematoma underwent reoperation in the perioperative period during hospitalization. Overall, 20 (7.4%) patients experienced complications after discharge up to 2 years postoperatively, including recurrences of neurological symptoms (n = 9), implant migration (n = 2), implant subsidence (n = 7), and others (n = 3). Two (0.7%) patients who experienced a recurrence of neurological symptoms underwent additional posterior foraminotomy within 2 years postoperatively. One (0.4%) patient underwent implant removal and conversion to fusion due to implant subsidence.
Conclusions:The overall complication and reoperation rates of TDR were relatively low: 1.5% and 1.1% in the perioperative period during hospitalization and 7.4% and 1.1% within the 2-year postoperative period after discharge, respectively. TDR achieved favorable outcomes with acceptable complication rates when performed under appropriate surgical indications.
Introduction: This study investigated brace treatment for patients with adolescent idiopathic scoliosis (AIS) to comprehensively evaluate the factors associated with curve progression, including the effects of in-brace correction rate (ICR) and objective brace compliance. Additionally, it aimed to establish a clinically useful optimal ICR threshold for effective curve progression control.
Methods:In this single-center retrospective analysis of prospectively collected data, 116 patients with AIS, with Cobb angles of 20°-40° and at least 1-year follow-up were included. Patients whose Cobb angles progressed by >5° were classified into the progressed group, whereas the others were categorized into the non-progressed group. Bracing time was objectively assessed using a thermometer.
Results: In this study, 19 (16.4%) patients were assigned to the progressed group. Open triradiate cartilage was significantly more frequent in the progressed group (22.2% vs. 2.6%, p= 0.011) whereas no significant differences were observed in demographics or pre-brace Cobb angles. The progressed group demonstrated a lower ICR (26.8% vs. 39.5%, p= 0.002) and shorter bracing time at 6 months (14.0 hours vs. 17.4 hours, p= 0.042). Multivariate logistic regression analysis revealed that Sanders grade (1-4), ICR, and bracing time were independently associated with Cobb angle progression (odds ratios: 7.01, 0.95, and 0.89, respectively; all p< 0.05). Based on receiver operating characteristic curve analysis, the ICR threshold of 38.3% was identified to achieve a clinically significant negative predictive value of 95%.
Conclusions:Under objective bracing time monitoring, skeletal maturity, ICR, and bracing time were crucial factors in preventing curve progression 1 year after brace initiation in patients with Cobb angles of 20°-40°. An ICR of 38.3% is recommended as the target when bracing adjustments are feasible.
Lumbar disc herniation (LDH) is one of the main causes of low back pain, and far lateral lumbar disc herniation is a specific type of LDH. Owing to the limitation of the bony structure and surrounding ligaments in the foraminal area, the closer the protrusion inside and outside the foramen is to the exiting nerve root ganglia, the more severe the compression. Therefore, the clinical symptoms of this type of LDH are more pronounced, and timely diagnosis and treatment are required. Some patients can experience pain relief through conservative treatment, whereas others require surgical intervention. Spine surgeons can choose different surgical options according to the patient's condition and their own surgical habits, such as traditional surgery, microendoscopic discectomy, percutaneous endoscopic lumbar discectomy, and unilateral biportal endoscopy. There are different characteristics between traditional surgery and minimally invasive surgery, and there are also different characteristics between different minimally invasive surgeries. This article reviews the anatomical structure, clinical manifestations, and various treatment approaches.
ObjectiveTo predict the onset of dysphagia in hospitalized patients with osteoporotic vertebral fractures (OVF) early after admission and to investigate cutoff values for risk factors.
Methods The subjects were 341 hospitalized patients with OVF. We excluded 30 cases as the required data could not be measured, and 25 cases with conditions that could contribute to dysphagia, such as neurological or respiratory comorbidities. Gender, age, number and level of OVF, collapse rate (CR) of OVF, thoracolumbar kyphosis angle (KA), bone mineral density (BMD), systemic skeletal muscle mass index (SMI), and body mass index (BMI) were examined by dividing the patients into those with dysphagia (the P group) and others (the N group).
Results There were 26 cases in the P group and 260 cases in the N group, with no significant difference in the male-female ratio, number, and level of OVF. The mean values of CR (%), KA in the P group/the N group were 40.0/36.1, 16.7/17.8, and the mean values of age, BMD (%), SMI (kg/m2), and BMI (kg/m2) in the P group/the N group were 86.4 /82.3, 64.5/71.6, 4.43/5.58, 20.0/22.1 in men, 85.7/83.4, 55.1/63.8, 4.43/4.99, 19.4/21.6 in women, with significant differences in SMI in men and women and BMD in women. Analysis of SMI and BMD in women using a multivariate logistic model with dysphagia as the dependent variable showed that low SMI was an independent risk factor. The cutoff value, sensitivity, specificity, and area under the receiver operating characteristic curve for SMI were calculated. For men, the values were 4.610 kg/m2, 0.867, 0.750, and 0.829, respectively, and for women, 4.410 kg/m2, 0.790, 0.571, and 0.687, respectively.
Conclusions A correlation was found between dysphagia and SMI in patients with OVF. For patients with SMI below the cutoff value, early swallowing evaluation and training intervention are considered important.
Background: Accurate pedicle screw placement is critical in spinal fusion surgery to prevent complications such as neurological and vascular injuries. While conventional intraoperative computed tomography (iCT) navigation systems enhance placement accuracy and reduce radiation exposure compared to fluoroscopic guidance, they can encounter line-of-sight issues that disrupt surgical workflows. The NextAR iCT navigation system aims to overcome these challenges by integrating an infrared camera directly onto surgical instruments, streamlining navigation and improving procedural efficiency.
Methods:This retrospective study evaluated the accuracy and safety of pedicle screw insertion using the NextAR navigation system in lumbar spinal fusion for degenerative diseases. We analyzed 307 screws using a CT-based grading system.
Results:Among the 307 screws inserted, only 8 (2.6%) exhibited minor deviations (grade 1 or 2), with no severe perforations (grade 3 or 4). There were no neurological or vascular complications related to screw placement. The NextAR system enabled precise pedicle screw insertion without the need for fluoroscopic guidance, eliminating radiation exposure for the surgical team.
Conclusions:The NextAR navigation system demonstrated high accuracy and safety in pedicle screw placement for lumbar degenerative diseases. By addressing line-of-sight issues inherent in traditional navigation systems and eliminating intraoperative radiation exposure, it offers significant procedural advantages. Further randomized controlled trials are needed to compare its effectiveness with other advanced navigation systems.
Introduction:This study aimed to compare the outcomes in patients who received non-steroidal anti-inflammatory drugs (NSAIDs) ≤90 days or 90 days-1 year after posterior cervical fusion (PCF) with those in patients who did not receive NSAIDs after surgery.
Methods:Using the MarketScan® Research Databases, we analyzed adults (18–90 years) who underwent PCF and adjusted for confounders with inverse probability of treatment weighting (IPTW) to compare outcomes in those receiving NSAIDs ≤90 days or 90 days-1 year after surgery and those not receiving NSAIDs within a year. In one analysis, we included single- and multi-level PCF, and in a sub-group analysis, we focused on single-level PCF. Outcomes included 30-day readmissions, pseudoarthrosis, hardware failure, and wound complications.
Results:After IPTW, NSAID use ≤90 days of single- and multi-level PCF was not associated with increased readmissions, pseudoarthrosis, or wound complications. However, NSAID use 90 days-1 year increased the odds of pseudoarthrosis and hardware failure (odds ratio 1.157, 95% confidence interval 1.075-1.245, p < 0.001). In single-level PCF, NSAIDs use ≤90 days or 90 days-1 year of surgery was not associated with increased odds of complications. No difference was observed in postoperative complications between patients who took COX-2 selective inhibitors and those who took non-selective NSAIDs.
Conclusions:NSAID use ≤90 days of surgery does not increase the risk of adverse outcomes for either single- or multi-level PCF, suggesting it may be a viable option for pain management. Postoperative NSAID use 90 days-1 year does not seem to increase complications in single-level PCF. However, caution is advised for multi-level fusions or cases with complex clinical factors, in which NSAID use from 90 days-1-year postoperatively may increase the risk of pseudoarthrosis and hardware failure.
Introduction:Surgical outcomes for adult patients with residual adolescent idiopathic scoliosis (AdIS) with a major thoracic curve are expected to be inferior to those of AIS but have not been well reported. This study aimed to evaluate surgical, radiographical, and clinical results in adult patients with AdIS and to characterize these patients by comparing their results with those of patients with adolescent idiopathic scoliosis (AIS).
Methods:Thirty-five patients with AdIS, who were diagnosed with AIS Lenke type 1 or 2 before the age of 19 years and underwent surgery after the age of 20 years, were included in the study. As a control group, 84 patients with AIS Lenke type 1 or 2 who underwent surgery before the age of 19 were included. Both groups were matched on the basis of the preoperative main thoracic (MT) and proximal thoracic (PT) Cobb angles, causing 30 patients to be selected in each group.
Results:The AdIS group exhibited a greater preoperative bending Cobb angle of the MT and PT curves (MT: 35.1° vs. 31.3°, PT: 17.8° vs. 13.8°) and a lower MT curve flexibility index than in the AIS group (36.6% vs. 42.2%). Postoperatively, the AdIS group had a higher number of fused intervertebral segments than did the AIS group (8.2 vs. 7.4), but the correction rate was comparable in the 2 groups. Moreover, the intraoperative time was longer and blood loss was larger in the AdIS group. In the Scoliosis Research Society (SRS) -22 score, self-image and mental health domains were significantly lower preoperatively in the AdIS group. Postoperative improvement of self-image domain was significantly greater in the AdIS group (Δ self-image: 1.6 vs. 0.9), and postoperative satisfaction was similar in the 2 groups.
Conclusions:Surgical invasiveness was increased in AdIS, and preoperative SRS-22 scores were lower in self-image and mental health domains than in AIS. However, postoperative SRS-22 scores were comparable, and postoperative self-image improvement was significantly greater in AdIS than in AIS.
Introduction: Proximal junctional kyphosis (PJK) in patients undergoing instrumented deformity correction surgery for adult spinal deformity (ASD) is found to be multifactorial. This review aims to provide comprehensive information on which factors affect PJK in ASD correction surgery including prevention strategies.
Materials and Methods: A literature review was conducted through a web search on PubMed with the following combination keywords: "proximal junctional kyphosis," "adult spinal deformity," and "risk factor" between January 2001 and June 2024. Primary outcomes of interest were divided into two groups: non-radiological parameters including patient characteristics and surgical techniques, and radiological parameters.
Results: The non-radiological parameters associated with PJK included age, body mass index, comorbidities, low bone quality, muscle degeneration, combined anterior–posterior surgical approach, rigid proximal instrumentation, upper instrumented vertebrae (UIV) selection in the junctional zone, long-segment fusion, and overcorrection. Moreover, lumbar lordosis, spinopelvic parameter, thoracic tilt, upper instrumented vertebra–femoral angle, fused spinopelvic angle, and UIV inclination were found to be the radiological parameters that influence the incidence of PJK in patient with ASD correction surgery.
Conclusion: Understanding the multifactorial aspects of PJK could aid in the preoperative planning and assessment for patients with ASD. Furthermore, the proposed correction should be based on an individualized approach.
Introduction
The pathogenesis of dropped head syndrome (DHS) involves factors like fat infiltration of the cervical extensor muscle, cervical degeneration, and sarcopenia, which are typically assessed using conventional imaging. Previous studies have demonstrated cervical and thoracic anterior tilt deterioration during gait in patients with DHS. However, the relationship between dynamic spinal balance and conventional imaging findings has not been investigated. The purpose of this study was to investigate the walking posture of patients with DHS using 3D gait motion analysis and to analyze the relationship between dynamic posture and conventional imaging factors, leading to the investigation of the pathophysiology of cervical imbalance during gait in patients with DHS.
Methods
Twenty-two patients with DHS were included. Global and cervical static alignments were assessed using whole spine radiography. 3D gait motion analysis was performed, and dynamic kinematic variables were segmented into the cervical and thoracic regions. The paraspinal muscle activity was assessed using wireless surface electromyography. The cervical deep extensor muscle (C-DEM) condition was assessed using magnetic resonance imaging. Correlations of changes in dynamic kinematic variables with paraspinal muscle activity and C-DEM condition were determined.
Results
A significant change in the anterior cervical and thoracic spine tilt was observed during gait. These changes were inversely correlated with thoracic paraspinal muscle activity. The change in the cervical anterior tilt was significantly correlated with the fat-free C-DEM at C3/C4 and C4/C5 and the fat infiltration rate of the C-DEM at C5/C6 and C7/T1.
Conclusion
The thoracic paraspinal muscle activity failed to respond to the deterioration of the thoracic anterior tilt, indicating a notable contribution to postural endurance during gait and to DHS pathogenesis. Evaluating the condition of the C-DEM could be an alternative for evaluating dynamic postural endurance and is clinically important when considering patient complaints regarding difficulties in daily activities.
Introduction: Cervical compressive myelopathy is a leading cause of spinal cord dysfunction in middle-aged and older adults. Although the pathological classification of cervical myelopathy is well established, the quantitative analysis of its imaging features remains underexplored. This study quantitatively evaluated the imaging characteristics of unilateral motor deficit cervical compressive myelopathy.
Methods: This retrospective observational study included patients who underwent surgery for cervical compressive myelopathy between 2009 and 2023. Pre-operative cervical magnetic resonance imaging (MRI) and postmyelographic computed tomography (CTM) axial images were assessed for spinal cord rotation, deformity, available space, and signal changes. Patients were classified into unilateral motor deficit (Group U) and symmetric transverse (Group ST) types, and were analyzed for specific imaging parameters.
Results: The final analysis included 119 of the 812 identified patients. Group U patients were younger (59.1 ± 13.8 years) and had higher Japanese Orthopaedic Association scores (10.6 ± 2.7) compared with Group ST patients (71.1 ± 11.0 years, 8.4 ± 2.3). Group U showed significant morphological differences, including a reduced anterior-subarachnoid space and increased spinal cord rotation on the affected side. Group U exhibited significant differences in the median fissure rotation angle (7.4° ± 6.7°) and anterior-aspect rotation angle ratio (1.26 ± 0.31) compared with Group ST (4.14° ± 3.87°, 1.10 ± 0.14). Receiver operating characteristic curve analysis identified specific cutoff values for distinguishing Group U (2.80° for median fissure rotation angle and 1.116 for anterior-aspect rotation angle ratio). The MRI-based detection sensitivity was lower in Group U (27.6%) compared with in Group ST (68.9%).
Conclusions: Unilateral motor deficits are associated with distinctive spinal cord rotational deformities, including a greater median fissure rotation angle and anterior-aspect rotation angle ratio. CTM is better than MRI for detecting unilateral motor deficits. Future research to improve treatment outcomes should focus on spinal cord circulation assessment using advanced imaging techniques.
Introduction Impaired standing alignment and postural instability diminish health-related quality of life (HRQOL). Reduced trunk muscle mass is correlated with worsened spinal alignment and HRQOL in patients with spinal disease. However, the interplay among standing balance, whole-body alignment, muscle mass, and HRQOL remains unclear. This study aimed to elucidate this relationship.
MethodsThis study evaluated the influence of whole-body alignment, standing balance, skeletal muscle mass (SMM), aging, and sex on HRQOL in healthy volunteers (HV; men/women: 37/63, median age: 45), patients with lumbar degeneration (LD; men/women: 100/100, median age: 65), and patients with spinal deformity (SD; men/women: 16/84, median age: 71). HRQOL was assessed using the Scoliosis Research Society-22 (SRS-22r). Whole-body alignment and standing balance were measured using EOS Imaging combined with simultaneous force plate measurements. SMM was measured using a medical body composition analyzer. Based on univariate analysis and multicollinearity, 10 selected parameters were used in multivariate logistic regression analysis to identify factors affecting SRS-22r.
ResultsThe SRS-22r score was significantly higher in the HV group than in the LD and SD groups; however, there were no significant differences between men and women. The whole-body alignment and standing balance were better in the HV group, followed by the LD and SD groups. The total-body SMM (SMM.total) of men was significantly lower in the LD and SD groups than in the HV group. In females, the SMM.total was significantly lower in the SD group than in the HV and LD groups. However, trunk SMM did not significantly differ among the three groups. Based on the multivariate analyses, diagnosis, body mass index (BMI), SMM.total, lumbar lordosis (LL), and T1 pelvic angle (TPA) were correlated with the SRS-22r score.
ConclusionHRQOL was negatively affected by spinal disease, as well as by higher BMI, lower SMM.total, and sagittal malalignment (smaller LL and greater TPA).
Introduction:Some cases of postoperative correction loss have been observed in the reduction of vertebral slippage using a percutaneous pedicle screw system for lumbar degenerative spondylolisthesis. We aimed to identify the risk factors for correction loss after minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) and to determine the effect of postoperative correction loss on postoperative clinical outcomes.
Methods:In this retrospective study, a total of 111 patients (mean age 69.5 years, 37 men and 74 women) who underwent single-level MIS-TLIF with slippage reduction for lumbar degenerative spondylolisthesis and were followed up for >1 year were included in the study. The correction loss group (group L) included those with a correction loss of ≥3 mm between immediately after surgery and 1 year after surgery, and the correction maintenance group (group M) included those with a correction loss <3 mm. Demographic data, preoperative and postoperative radiographic measurements, and clinical outcomes were collected, and the risk factors in group L and clinical outcomes in the two groups were analyzed statistically.
Results:Groups L and M comprised 19 and 92 cases, respectively. High pelvic incidence-lumbar lordosis (odds ratio [OR]: 1.16, 95% confidence interval [CI]: 1.07-1.25, p < 0.001), high slip vertebra slope (OR: 1.22, 95% CI: 1.07-1.39, p < 0.001), and ≥10° segmental angulation (OR: 15.00, 95% CI: 3.04-73.95, p = 0.0022) were risk factors for correction loss; however, low bone density was not. The Oswestry Disability Index and Visual Analog Scale scores for low back pain, leg pain, and leg numbness were not significantly different between both groups; however, the bone union rate at 6 months postoperatively was significantly lower in group L (p = 0.0020).
Conclusions:Postoperative correction loss was influenced by preoperative sagittal alignment and instability rather than bone density. Patients with correction loss tend to have prolonged bone union and should be closely monitored.
The study investigated the complications of adult spinal deformity (ASD) surgery in Japan in 2022 using the Japanese Orthopedic Association National Registry/Japanese Society for Spine Surgery and Related Research Database (JOANR/JSSR-DB).
Methods
Among the 158,407 patients registered in JOANR/JSSR-DB, 4,822 patients aged ≥19 years (1,115 males [23.1%], 3,707 females [76.9%]) were included in this study. Diagnoses were scoliosis in 1,961 patients (40.7%), kyphosis in 1,613 patients (33.4%), and kyphoscoliosis in 1,248 patients (25.9%). Intra-operative and postoperative/systemic complications (within 30 days) were investigated.
Results
The age distribution was 468 (9.7%) aged 19–39, 855 (17.7%) aged 40–64, 1,779 (36.9%) aged 65–74, and 1,720 (35.7%) individuals aged ≥75 years, with 72.6% of the total population aged ≥65 years. The total complication rate was 11.8% (567 patients), with 6.2% in patients aged 19–39 years, 12.6% in patients aged 40–64 years, 11.6% in patients aged 65–74 years, and 13.0% in patients aged ≥75 years, whose rate was significantly higher (p < 0.001). Intra-operative complications occurred in 215 patients (4.5%). Dural tear in 110 patients (2.3%), massive bleeding (>2,000 ml) in 54 (1.1%), implant-related complications in 14 (0.3%), and intra-operative nerve injury in 10 patients (0.2%). Postoperative complications occurred in 266 patients (5.5%). Lower extremity paralysis in 99 patients (2.0%), surgical site infection in 55 (1.1%), vertebral body or endplate injury in 25 (0.5%), epidural hematoma in 18 (0.4%), and weakness of the iliopsoas muscle due to lateral lumbar interbody fusion in 21 patients (0.4%). Systemic complications occurred in 162 patients (3.4%) with urinary tract infection in 29 (0.6%) and postoperative delirium in 26 (0.5%).
Conclusion
While the 11.8% total complication rate was lower than previous reports, rates were higher in patients aged ≥75, indicating the need for careful perioperative management in elderly patients.
Introduction:Japan is experiencing a significant demographic shift characterized by a declining birthrate and an aging population. A previous report indicated a discrepancy between the trends in the number of spinal surgeries performed for minors and the overall population dynamics. Japan has the National Database of Health Insurance Claims and Specific Health Checkups (NDB), which contains 99.9% of public health insurance claims from hospitals and 97.9% from clinics. This study aimed to investigate the annual number of scoliosis surgeries performed on patients aged 19 years in Japan, evaluate trends in relation to the overall population dynamics, and examine potential factors contributing to the observed changes.
Methods:This retrospective study utilized NDB and census data. Scoliosis surgeries were identified using K-codes specific to the procedure. Population data were estimated using census and national birth records released by the Japan Cabinet Office. The number of surgeries per 100,000 minors was calculated, and trends were analyzed from 2014 to 2021.
Results:The number of scoliosis surgeries for patients under 19 years old increased from 1,282 in 2014 to 1,850 in 2021, despite a decrease in the number of patients under 19 years old. The rate of scoliosis surgeries per 100,000 minors increased from 5.6 in 2014 to 9.1 in 2021, whereas other spinal fusion procedures for minors did not show significant changes during the same period.
Conclusions:Despite a decline in the underage population, the number of scoliosis surgeries among minors has paradoxically increased in Japan. Improvements in screening tools and the April 2016 change in the law mandating a full motor examination, including scoliosis testing, may have affected this trend. Further follow-up studies are required.
Introduction
Postoperative infection remains a significant concern and technical challenge for spine surgeons. Preoperative albumin level may predict risk of infection, but no definitive consensus regarding the optimal preoperative albumin level in anterior cervical discectomy and fusion (ACDF) has been reached. Therefore, this study aimed (1) to determine the impact of preoperative albumin on complications following ACDF and (2) to identify optimal albumin threshold that minimizes the likelihood of infection following ACDF.
Methods
A retrospective cohort analysis was performed using a national database. Patients with a preoperative measurement of albumin prior to ACDF were included, whereas patients undergoing multilevel ACDF were excluded. Stratum-specific likelihood ratio (SSLR) analysis was conducted to determine data-driven albumin strata that minimized the likelihood of infectious complications within 30 days of ACDF.
Results
A total of 30,896 ACDF patients were included in this study. Stratum-specific likelihood ratio analysis identified two albumin strata: 1–3 and 3+ g/dL prior to surgery. Relative to the 3+ g/dL cohort, the 1–3 g/dL cohort was more likely to experience 30-day infectious complications such as deep surgical site infection (SSI) (OR: 8.02, P < 0.001) and SSI domain (OR: 4.85, P < 0.001).
Conclusion
This study demonstrates a significant association between preoperative albumin level and infectious complications following ACDF. These results emphasize the importance of integrating nutritional management strategies into the broader context of surgical decision-making, thus contributing to enhanced patient outcomes and quality of care in spine surgery.
Introduction:Acute celiac artery compression syndrome occurs after corrective surgery for adult spinal deformity. It occurs due to ischemic abdominal organ necrosis, caused by compression of the celiac artery (CA) and superior mesenteric artery by the median arcuate ligament. There are no studies measuring the extent of CA or superior mesenteric artery stenosis. Therefore, this study aimed to investigate stenotic changes in the CA after adult spinal deformity surgery.
Methods:We obtained contrast-enhanced computed tomography scans for 21 pre-and postoperative patients with adult spinal deformity. Three-dimensional reconstruction computed tomography measured the degree of stenosis in the CA trunks. Stenosis was considered worse if it progressed from being less than 35% before surgery to over 50% afterward. This study investigated the relationship between worsening CA stenosis and the median arcuate ligament crossing the proximal portion of the celiac axis (median arcuate ligament overlap) or the distance between the median arcuate ligament and the anterior edge of the vertebra (DMV). Change in spinal parameters was defined as differences between pre- and postoperative values.
Results:The average stenosis degree in the CA was 9.4% ± 11.4% pre-operatively, which increased to 25.1% ± 21.8% post-operatively (P = 0.002). In contrast, the stenosis degree in the superior mesenteric artery was 5.6% ± 7.1% before and 7.9% ± 10.2% after surgery (P = 0.177). CA stenosis worsened in four patients (19.0%), which was significantly associated with preoperative median arcuate ligament overlap (P = 0.012) and ΔDMV (P < 0.001).
Conclusions:Nineteen percent of patients undergoing adult spinal deformity correction surgery experienced worsened CA stenosis. Risk factors were preoperative median arcuate ligament overlap and DMV shortening during adult spinal deformity correction surgery. Moreover, patients with preoperative CA stenosis and median arcuate ligament overlap were at risk for acute celiac artery compression syndrome following adult spinal deformity surgery.
Introduction:To compare the clinical outcomes between a full-endoscopic transforaminal approach lumbar interbody fusion (TF-LIF) using the percutaneous endoscopic transforaminal lumbar interbody fusion (PETLIF) system and a minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF).
Methods: A total of 102 patients (80 females, 22 males; mean age: 70.0 years) with degenerative lumbar spine disorders who underwent PETLIF and were followed up for 2 years were assigned to the PETLIF group. Based on age, sex, and operated lumbar levels in the PETLIF group, 100 patients (71 women and 29 men; mean age: 68.9 years) who underwent MIS-TLIF were randomly selected and included in the MIS-TLIF group. This retrospective investigation included surgical data, radiographic assessment, and clinical outcomes.
Results: The fusion rate was 95.1% and 96.0% in the PETLIF and MIS-TLIF groups, respectively (P = 0.38). The decrease in hemoglobin levels from before surgery to 1 day after surgery was significantly lower in the PETLIF group than in the MIS-TLIF group (P < 0.01). Five patients had detectable transient neurologic disorders after PETLIF that were resolved within 3 months. The increase in the local lordosis angle from before surgery to the final follow-up was significantly higher in the MIS-TLIF group than in the PETLIF group (P < 0.01). Clinical scores were comparable between the two groups.
Conclusions:Compared with MIS-TLIF, PETLIF showed excellent bone fusion rate and clinical outcomes. It was minimally invasive, resulting in less blood loss. However, exiting nerve root injury was a PETLIF-specific complication, and proper preventive management, including techniques to enlarge the Kambin's triangle, is required.
Introduction:To estimate natural standing sagittal alignment in patients with adult spinal deformity (ASD), we previously reported the normative values of anatomical pelvic parameters in a healthy population, based on the anterior pelvic plane (APP), and observed the relationships between anatomical and positional pelvic parameters in the standing position. As the second step, we aim to investigate the relationships between anatomical pelvic parameters and standing spinal sagittal alignment in a healthy population.
Methods:We analyzed biplanar, slot-scanning, full-body stereo radiography of 140 healthy Japanese volunteers (mean age, 39.5 years; 59.3% women). The APP was defined by bilateral anterior superior iliac spines and anterior surface of the pubis symphysis. Anatomical sacral slope (aSS) and anatomical pelvic tilt (aPT) were calculated as angles of the SS and PT regarding the APP.
Results:The APP was tilted anteriorly in the sagittal plane by an average of 0.7°. Anatomical pelvic parameters significantly correlated with standing sagittal parameters, except for cervical lordosis and T4–12 thoracic kyphosis (TK) (p<0.05). L4-S1 lumbar lordosis (LL) significantly correlated with aPT and aSS, but not with pelvic incidence (PI). In addition, T1–12 TK significantly correlated with aSS. Multiple linear regression analysis for lumbar alignment produced the following equations: L1–S1 LL (°) = 0.588 × aSS + 30.522, L4–S1 LL (°) = 0.165 × aSS − 0.248 × aPT + 32.825, lordosis distribution index (%) = −0.662 × PI + 102.8.
Conclusions:Novel relationships in a healthy population were identified between the anatomical characteristics of the pelvis and standing sagittal parameters not represented by PI. This novel measurement concept based on the APP may estimate natural standing sagittal alignments and proportions using anatomical pelvic parameters in ASD.