Long-term results comparison after anterior cervical discectomy with BGS-7 spacer (NOVOMAX®-C) and allograft spacer: A prospective observational study.

Introduction: In an anterior cervical discectomy and fusion (ACDF), various types of graft materials including autograft, allograft, and synthetic graft have been used to achieve adequate spinal fusion. Allograft spacer is mainly used in cervical fusion, especially in the anterior approach. The synthetic bone graft material BGS-7(CaO-SiO2-P2O5-B2O3, bioactive Glass-Ceramics) can bind with surrounding bone tissue by forming a hydroxyapatite layer bone bridge, leading to faster graft osseointegration. This study was conducted to compare long-term clinical outcome of BGS-7 spacer and allograft spacer for anterior cervical discectomy and fusion surgery. Materials and Methods: From September 2014 to December 2016, Consecutive anterior cervical discectomy and fusion surgeries using a BGS-7 spacer (N = 18) and Allograft spacer (N = 26) were compared for postoperative clinical outcomes. Radiologic assessments were performed, and Instrumental failure, including breakage, cage migration, subsidence were observed and Fusion status were analyzed. Finite element analysis was performed for simulating mechanical stress between the vertebral body and implant. Clinical outcomes were evaluated using neck VAS, NDI, and JOA on the patient's final follow-up visits. Results: Among the 44 patients who underwent an anterior cervical discectomy and fusion surgery using the BGS-7 spacer and Allograft spacer, there were 30 men and 14 women. The average age at the operation was 47.69 ± 10.49 in allograft spacer and 51.67 ± 11.03 in BGS-7 spacer. The mean follow-up period was 89.18 ± 5.44 months. Twenty three (88.46%) patients in allograft spacer and 20(100%) patients in BGS-7 spacer were demonstrated radiologic evidence of interbody fusion in last OPD, which accounts for fusion grade 4 or 5. Peak stresses were 343.85 MPa in allograft spacer, and 132.55 MPa in BGS-7 spacer. Long-term clinical outcomes including neck VAS, NDI, and JOA didn't show statistical differences between the two groups. There were no adverse events related to the BGS-7 spacer.10.3389/fbioe.2023.110046. Conclusion: The BGS-7 spacer demonstrated reliability as a spacer in anterior cervical discectomy and fusionF surgery without instrumental failure. Early stabilization with a bony bridge formation was observed at the intermediate follow-up period, and the long-term clinical outcome was favorable at more than 60 months after surgery without any adverse events. Thus, the BGS-7 spacer is a safe and effective alternative to the allograft spacer in anterior cervical discectomy and fusion surgery.

Looking Back on 2022 With Neurospine.

On behalf of the editorial office of Neurospine, we would like to extend our appreciation to all the readers who have supported the journal throughout the year. Neurospine was established in March 2018 through a collaboration of 3 leading spinal neurosurgery societies from Japan, Korea, and Taiwan. Since then, Neurospine has continued to enhance its academic impact, serving as a platform for sharing knowledge and information related to the management of spinal diseases. In this article, we aim to present the bibliometrics of Neurospine, including the submission and publication of manuscripts and the peer review process. We are looking forward to continued growth and serving the academic community to the best of our ability.

Metallic Artifact Reduction of Multiacquisition With Variable Resonance Image Combination Selective-Short Tau Inversion Recovery for Postoperative Cervical Spine With Artificial Disk Replacement: A Preliminary Study.

OBJECTIVE: This study aimed to evaluate multiacquisition with variable resonance image combination selective short tau inversion recovery (MAVRIC SL STIR) for metallic artifact reduction in magnetic resonance imaging (MRI) of postoperative cervical spine with artificial disk replacement. METHODS: A porcine cervical spine with artificial disk replacement was subject to 3 T MRI with variable fat-suppressed fluid-sensitive sequences. Five volunteers underwent MRI with MAVRIC SL STIR and STIR. Quantitative and qualitative analyses were performed for metallic artifact reduction. RESULTS: MAVRIC SL STIR showed the least signal void areas in the tissue phantom and volunteer study. In the tissue phantom study, MAVRIC SL STIR showed the best visualization of anatomic structure, least distortion, and signal pile-up. However, it ranked last for the homogeneity of fat suppression among sequences. In the volunteer study, MAVRIC SL STIR showed better visualization of anatomic structure and lesser distortion, but showed worse image quality of the spinal cord than STIR in the sagittal plane (P < 0.05). CONCLUSIONS: MAVRIC SL STIR might be useful for visualization of anatomy by reduction of signal void areas and distortion in the operated site but should be used as a complement to STIR for evaluation of the spinal cord signal change.

Clinical, Radiographic, and Genetic Analyses in a Population-Based Cohort of Adult Spinal Deformity in the Older Population.

OBJECTIVE: This study aimed to identify the sagittal parameters associated with health-related quality of life and genetic variations that increase the risk of adult spinal deformity (ASD) onset in the older population. METHODS: We recruited 120 participants who had a sagittal vertical axis > 50 mm in a sagittal imbalance study. Sagittal radiographic parameters, cross-sectional area, and intramuscular fatty infiltration using the Goutallier classification in the paraspinal lumbar muscles were evaluated. Functional scales included the self-reported Oswestry Disability Index (ODI), 36-item Short Form Health Survey (SF-36), and visual analogue scales (VAS) for back and leg pain. We performed whole-exome sequencing and an exome-wide association study using the 100 control subjects and 63 individuals with severe phenotypes of sagittal imbalance. RESULTS: Pelvic incidence minus lumbar lordosis (PI-LL) mismatch was negatively associated with the SF-36 and positively correlated with ODI and VAS for back and leg pain. PI-LL was related to the quality and size of the paraspinal muscles, especially the multifidus muscle. We identified common individual variants that reached exome-wide significance using single-variant analysis. The most significant single-nucleotide polymorphism was rs78773460, situated in an exon of the SVIL gene (odds ratio, 9.61; p = 1.15 × 10-9). CONCLUSION: Older age, higher body mass index, and a more significant PI-LL mismatch were associated with unfavorable results on functional scales. We found a genetic variation in the SVIL gene, which has been associated with the integrity of the cytoskeleton and the development of skeletal muscles, in severe ASD phenotypes. Our results help to elucidate the pathogenesis of ASD.

Natural history and aggravating factors of sagittal imbalance in marked sagittal deformity compared with mild to moderate sagittal deformity: A prospective cohort study.

Sagittal imbalance is a multifactorial complex deformity that can arise from a variety of causes such as spinal stenosis, sarcopenia, vertebral fracture, and neuromuscular diseases. Furthermore, there is lack of research regarding spinal and general conditions that precede the development of sagittal imbalance. Our aim was to evaluate aggravating factors, such as natural history, for sagittal imbalance in a cohort comprising elderly individuals by conducting various examinations.We recruited 96 participants who had a sagittal vertical axis (SVA) larger than 50 mm in a sagittal imbalance study. Finally, 69 participants were followed up and enrolled this study after 2 years. We evaluated full spine radiographs, magnetic resonance imaging (MRI), bone mineral density, and health-related quality of life from patients survey and analyzed factors associated with aggravation of sagittal imbalance. Aggravation was defined by an SVA > 30 mm and T1 pelvic angle (T1PA) > 3° in the third year compared to SVA and T1PA values of the first year.Eighteen participants of the follow-up group had a sagittal imbalance aggravation. According to the deformity severity in the first-year evaluations, the marked deformity group (38 participants) defined as Schwab classification had 11 (28.9%) participants presenting with sagittal imbalance aggravation. These participants had larger mean values of Schwab sagittal modifiers and T1PA compared with the nonaggravation participants. Logistic regression analysis showed a higher pelvic incidence (PI) (OR = 1.201, 95% CI = 1.015-1.422, P = .033) and a small multifidus (MF) volume (OR = 0.991, 95% CI = 0.983-1.000, P = .043) correlated with sagittal imbalance aggravation.From the follow-up group, 18 (26%) subjects of total 69 participants presented a deteriorated sagittal imbalance. A higher PI and smaller MF volume correlated with the aggravation of sagittal imbalance. We should consider that high PI and small MF volume are associated with aggravation of sagittal imbalance.

Is Adjacent Segment Disease More Frequent in Proximal Levels in Comparison with Distal Levels? Based on Radiological Data of at Least 2 Years Follow Up with More than 2 Level Thoracolumbar Fusions.

OBJECTIVE: The purpose of this retrospective study was to determine which of the proximal adjacent segment disease (ASD) and distal ASD was more prevalent and what parameters is more related to ASD in proximal levels and distal levels after more than 2 levels fusions. METHODS: The medical records were reviewed retrospectively for 856 cases. A total of 66 cases of ASD were enrolled. On preop magnetic resonance imaging, disc degeneration was measured at the upper and lower parts of surgically treated levels and confirmed by the commonly used Pfirrmann grade. Segmental flexibility in sagittal plane was embodied in segment range of motion (ROM) obtained through flexion and extension X-ray before surgery. Coronal angle was recorded as methods Cobb's angle including fusion levels preoperatively. For the comparison of categorical variables between two independent groups, the chi-square test and Fisher exact test were performed. RESULTS: Proximal ASD and distal ASD were 37/856 (4.32%) and 29/856 (3.39%), respectively. The incidence of proximal ASD was relatively high but insignificant differences. In comparison between ASD group and non ASD group, proximal Pfirmman was higher in proximal ASD and distal Pfirmman was higher in distal ASD group (p=0.005, p<0.008, respectively). However, in the ROM, proximal ROM was higher in proximal ASD, but distal ROM was not different between the two groups (p<0.0001, p=0.995, respectively). Coronal angle was not quite different in both groups (p=0.846). CONCLUSION: In spite of higher frequency in ASD in proximal level in spinal fusion, it is not clear that incidence of ASD in proximal level is not higher than that of distal ASD group in more than 2 level thoracolumbar fusions. Not only Pfirrmann grade but also proximal segmental ROM is risk factor for predicting the occurrence of ASD in patients more than 2 level of thoracolumbar spine fusion operation excluding L5S1.

Prospective Observational Cohort Study of Health-related Quality of Life: Marked Adult Sagittal Deformity (ASD) in Comparison With Mild to Moderate ASD.

STUDY DESIGN: Retrospective analysis of prospective observational cohort OBJECTIVE.: This study assessed the difference in health-related quality of life (HRQOL) between participants with a mild to moderate adult sagittal deformity (ASD) (sagittal vertical axis [SVA] ≤9.5 cm) and those with a marked deformity (SVA >9.5 cm). We also evaluated predisposing factors for a marked deformity. SUMMARY OF BACKGROUND DATA: Sagittal imbalance is closely associated with HRQOL for the patient. However, how the effect changes depending on the degree of imbalance has not been fully evaluated. The understanding of the predisposing factor associated with marked deformity also lacks. METHODS: A total of 124 elderly persons with a stooping posture were enrolled. Questionnaires related to HRQOL were administered. Sagittal alignment parameters and pelvic parameters were measured with a whole spine x-ray. Lumbar spine magnetic resonance imaging was used to assess the presence of pathologic conditions, muscle quality and quantity. Multivariate logistic regression analysis was conducted to analyze potential risk factors. RESULTS: Marked ASD was associated with female sex, lower height and weight, and osteoporosis (P < 0.05). Back pain (assessed by a visual analogue scale) and the Oswestry Disability Index were significantly higher in the marked deformity group (P = 0.012, 0.002, respectively). Multivariate logistic regression analysis showed significant relationships between the following parameters and marked deformity: preexisting compression fracture (odds ratio [OR] = 7.793; 95% confidence interval [CI], 1.527-39.768), severe L5/S1 Pfirrmann disc degeneration grade (OR = 1.916; 95% CI, 1.086-3.382), and lower quantities of multifidus and psoas muscles (OR = 0.994, 0.997; 95% CI, 0.991-0.998, 0.994-0.999, respectively). CONCLUSION: Participants with a marked ASD showed different features from those with a mild to moderate ASD. This study also implies that anatomical factors, including the vertebrae, intervertebral discs, and paraspinal muscles, synergistically contribute to progression into marked deformity. LEVEL OF EVIDENCE: 3.

Does minimally invasive fusion technique influence surgical outcomes in isthmic spondylolisthesis?

OBJECTIVE: To compare the clinical and radiographic results between open transforaminal interbody fusion (TLIF-O) and minimally invasive TLIF (TLIF-M) for single-level low grade isthmic spondylolisthesis (IS). METHODS: This study enrolled 45 patients who underwent single-level TLIF with low grade IS. The patients were divided into two groups according to operative method: TLIF-M (20 patients) and TLIF-O (25 patients). TLIF-O group was matched with TLIF-M. RESULTS: At one-year postoperatively, there were no significant differences in any radiologic parameters between the two groups. Perioperative results such as blood loss, operation time, and hospital stay were superior in TLIF-M than in TLIF-O. Fusion was achieved in 17 of 20 patients (85.0%) in TLIF-M and 23 of 25 (92.0%) patients in TLIF-O. Back Visual Analog Scale (VAS) and Oswestry Disability Index (ODI) scores of TLIF-O were significantly lower than TLIF-M at one (back VAS, ODI) and six months (ODI) postoperatively. CONCLUSIONS: TLIF-M and TLIF-O produced similar clinical and radiological outcomes, including reduction of spondylolisthesis and disc space height restoration at one-year follow-up for single-level low grade IS. However, considering perioperative outcomes, back pain, and quality of life, TLIF-M might be a better option for single-level low grade IS compared to TLIF-O.

Herniated Discs at the Cervicothoracic Junction.

BACKGROUND: Disc herniations at the cervicothoracic junction (C7-T1 level) are unusual, and there have only been a few studies of patients with herniated C7-T1 discs. In addition, previous studies did not focus on the mechanism and causes of solitary cervicothoracic junction disc herniation. The authors investigated the characteristics, symptom duration, clinical course, and biomechanics of cervicothoracic junction disc herniation by comparing patients with C7-T1 disc herniation (C7-T1 group) with control groups. METHODS: Thirty-six patients who underwent solitary C7-T1 single-level disc surgery between 2006 and 2015 were included. For radiographic comparison, patients in a herniated C5-C6 disc group and the healthy control group were cohort matched. RESULTS: In the C7-T1 group, the disc herniation mainly occurred in the foraminal space (P < 0.0001). The C7-T1 group was significantly associated with a history of trauma (P < 0.0001). In addition, the cervical vertebral body was more readily observed on plain lateral radiographs in the C7-T1 group (7.36 ± 0.068). Patients in the C5-C6 group tended to have the sternal notch more frequently located above the T2-T3 disc space than other groups (P = 0.014). CONCLUSIONS: C7-T1 disc herniation demonstrates unique characteristics. Understanding the features of disc herniation at the cervicothoracic junction would be helpful for optimal care.

Efficacy and Safety of Full-endoscopic Decompression via Interlaminar Approach for Central or Lateral Recess Spinal Stenosis of the Lumbar Spine: A Meta-analysis.

STUDY DESIGN: A meta-analysis of five retrospective cohort studies. OBJECTIVE: The aim of the study was to delineate the efficacy and safety of full-endoscopic decompression via the interlaminar approach for central or lateral recess spinal stenosis of the lumbar spine using a meta-analysis. SUMMARY OF BACKGROUND DATA: The paradigm of spinal endoscopy is shifting from treatment of soft disc herniation to that of lumbar spinal stenosis. Technical advancements have enabled full-endoscopic decompression in spinal stenosis surgery. There is few strong evidence supporting this surgical technique, and clinicians usually rely on their own opinions and experiences. METHODS: A systematic search of electronic databases, including PubMed, EMBASE, Cochrane Library, Web of science, and KoreaMed, up to August 2017 was performed to identify studies concerning full-endoscopic decompression via the interlaminar approach for lumbar spinal stenosis. Changes in clinical outcomes [Oswestry Disability Index (ODI) and Visual Analog Scales (VAS) for back and leg pain] were compared with the minimal clinically important difference (MCID) for each item. We then calculated the mean differences and 95% confidence intervals (95% CIs) using random-effects models. RESULTS: We included data from five studies involving 156 patients at 6- and 12-month follow-ups. The majority of enrolled papers included patients with neurogenic claudication due to central stenosis refractory to conservative management and excluded patients with significant instability or previous surgery. The overall mean difference of patients with ODI and VAS scores for leg and back pain exceeded the criteria for MCID. ODI scores improved by 41.71 (95% CI, 39.80-43.62) after the surgery, which was twice the MCID. The VAS leg and back pain scores improved by 5.95 (95% CI, 5.70-6.21) and 4.22 (95% CI, 3.88-4.56), respectively, indicating statistically significant improvement over the MCID. CONCLUSION: Successful clinical outcomes can be achieved with full-endoscopic decompression via the interlaminar approach for lumbar central spinal stenosis in patients for the defined indications. LEVEL OF EVIDENCE: 2.

Surgical Outcomes After Segmental Limited Surgery for Adjacent Segment Disease: The Consequences of Makeshift Surgery.

BACKGROUND: To minimize surgical morbidity, surgeons may opt to perform segmental limited surgery instead of fusion extension for adjacent segment disease (ASD) after lumbar fusion surgery. This study evaluated clinical outcomes from segmental limited surgery without fusion extension for ASD and assessed which clinical factors were associated with reoperation after segmental limited surgery. METHODS: Medical data of 50 patients who underwent segmental limited surgery for ASD after lumbar fusion surgery between 2005 and 2015 were reviewed. Demographic data, ASD type, preoperative disc and facet degeneration, ASD location, and surgical summary were collected. The primary outcome was reoperation rate at 24 months after surgery. RESULTS: Of patients, 28 (56%) experienced recurrent radiculopathy (visual analog scale score ≥4). Revision surgery was performed in 22 patients (44%). Reoperation was performed more frequently in multilevel fusion first-surgery cases (15/23; 65.2%) than single-level fusion first-surgery cases (7/27; 25.9%; P = 0.005). The lowermost mobile segment group had a lower reoperation-free survival rate than the other group (hazard ratio = 9.85, 95% confidence interval 1.32-73.54, P = 0.01 [log-rank]). The 2-year reoperation-free survival rate for the lowermost mobile segment group was 31.5%, whereas the rate for the other group was 83.3%. CONCLUSIONS: Segmental limited surgery as a treatment for ASD after lumbar fusion surgery is likely to fail frequently and result in a high rate of recurrent radiculopathy and revision surgery. Fusion extension surgery is especially recommended for ASD at the lowermost mobile segment owing to the high failure rate.

Clinical relation among dural adhesion, dural ossification, and dural laceration in the removal of ossification of the ligamentum flavum.

BACKGROUND CONTEXT: Dural laceration frequently occurs during surgery in patients with ossification of the ligamentum flavum (OLF), mainly because of dural adhesion (DA) and dural ossification (DO) between the ligamentum flavum and the dura mater. However, the radiological predictive factors of DA in OLF have rarely been reported. PURPOSE: The objective of this study was to determine the preoperative radiological signs for predicting intraoperative DA in OLF by using preoperative magnetic resonance imaging (MRI) and computed tomography (CT). STUDY DESIGN: This is a retrospective study. PATIENT SAMPLE: This study included 182 patients who underwent decompressive laminectomy and OLF removal from 2005 to 2014. OUTCOME MEASURE: Demographic data, preoperative neurologic status, surgical procedure and results, and intraoperative and postoperative complications were analyzed. Clinical outcome was assessed with the Japanese Orthopaedic Association score. MATERIALS AND METHODS: Depending on the morphologic appearance of OLF in preoperative radiographs, we aimed to investigate the prevalence of intraoperative DA and DO. We used the following factors of representative classifications: (1) surface appearance, (2) "double-layer" or "tram-track" sign, (3) cross-sectional area of the stenosed level, (4) Sato classification as axial classification, (5) Kuh classification as sagittal classification, and (6) high-signal-intensity change on T2-weighted MRI. RESULTS: Intraoperative evidence of DA was observed in 52 patients (29%), and DO was observed in 23 patients (13%). Twenty-seven patients (15%) had dural laceration during surgery. Statistically, DA was closely associated with the non-uniform type of surface appearance (odds ratio 5.396, p=.001) and with the presence of either a double-layer sign or a tram-track sign (odds ratio 11.525, p<.001). In the preoperative CT and MRI, 21 out of 23 patients with DO showed a "double-layer sign" or a "tram-track sign." CONCLUSIONS: This study identified two predictive factors of DA in OLF, which were the non-uniform surface appearance and the presence of a double-layer sign or a tram-track sign. The presence of DO in OLF was closely associated with a double-layer sign or a tram-track sign in the preoperative radiological images.

Importance of Hematoma Removal Ratio in Ruptured Middle Cerebral Artery Aneurysm Surgery with Intrasylvian Hematoma.

OBJECTIVE: Ruptured middle cerebral artery (MCA) aneurysm with intrasylvian hematoma usually accompanied by progressive cerebral swelling with poorer outcomes. The authors present characteristics and importance of intrasylvian hematoma removal in the aneurysm surgery. MATERIALS AND METHODS: From 2012 February to 2014 March, 24 aneurysm surgeries for ruptured MCA aneurysms with intrasylvian hematoma were performed in the authors' clinic. The patients were classified according to three groups. Group A included patients who underwent decompressive craniectomy within a few days after aneurysm surgery due to progressive cerebral swelling, group B included patients for whom decompression was not necessary, and group C included patients who showed severe cerebral swelling on admission and decompressive craniectomy and aneurysm surgery in one stage. RESULTS: The mean hematoma volume on admission was 28.56 mL, 24.96 mL, and 66.78 mL for groups A, B and C, respectively. Removal of a larger amount of hematoma was observed on postoperative computerized tomography scan in groups B and C (63.2% and 59.0%) compared with group A (33.4%). Although no statistical difference was found between group A and group B (p = 0.115), it tends to show the lesser amount of hematoma removed, the more likely cerebral swelling will progress. CONCLUSION: The lesser amount of hematoma in ruptured MCA aneurysm with intrasylvian hematoma tends to show benign clinical course than larger amounts. But, even if the hematoma is not easily removed in the operation, we suggest the other procedures such as continuous external catheter drainage of hematoma to avoid unnecessary coagulation or brain retraction.

Changes in Bone Metabolism in Young Castrated Male Rats.

PURPOSE: To determine the window of time during which osteoporosis affects the management of spinal surgery and the mechanism of bone metabolism changes in males with osteoporosis by examining changes in bone metabolism in young castrated male rats. MATERIALS AND METHODS: A total of 30 Sprague-Dawley rats were randomly allocated into two study groups. Group 1 (control) received a sham surgery and Group 2 received bilateral orchiectomy to change bone mineral density (BMD). Serum osteocalcin, alkaline phosphatase (ALP), and collagen type 1 cross-linked C-telopeptide (CTX) were analyzed at postoperative date (POD) 8, 10, and 12 weeks. BMDs were measured using micro computed tomography scans. RESULTS: Femoral and lumbar BMDs were decreased in the orchiectomy groups. BMDs in the sham and orchiectomy groups showed statistically differences at POD 8, 10, and 12 weeks for the femur (p=0.032, 0.008, 0.008) and lumbar spine (p=0.151, 0.008, 0.008, respectively). Serum osteocalcin, ALP, and CTX decreased gradually; however, N-terminal type 1 procollagen (P1NP) showed a slight increase yet no significant change. CONCLUSION: In young castrated male rats, a significant decrease in BMD was observed after orchiectomy due to the mixture of two detrimental factors. Young castrated male rats did not reach peak BMD. Increased bone turnover causes bone resorption to exceed bone formation. This study may contribute to the creation of a valuable model for studies of male osteoporosis and the spinal surgery field.

WITHDRAWN: Characteristics of patients with herniated discs at the cervicothoracic junction.

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Paraspinal muscle, facet joint, and disc problems: risk factors for adjacent segment degeneration after lumbar fusion.

BACKGROUND CONTEXT: Adjacent segment degeneration (ASD) is one of the major complications after lumbar fusion. Several studies have evaluated the risk factors of ASD. Although the paraspinal muscles play an important role in spine stability, no study has assessed the relationship between paraspinal muscle atrophy and the incidence of ASD after lumbar fusion. PURPOSE: In the present study, we aimed to verify the known risk factors of ASD, such as body mass index (BMI), preoperative adjacent facet joint degeneration, and disc degeneration, and to assess the relationship between paraspinal muscle atrophy and ASD. STUDY DESIGN: This is a retrospective 1:1 pair analysis matched by age, sex, fusion level, and follow-up period. PATIENT SAMPLE: To calculate the appropriate sample size for the study, we performed a pre-study analysis of the paraspinal muscle cross-sectional area (CSA), and estimated that at least 35 cases would be needed for each group. Among the 510 patients who underwent posterior lumbar fusion for degenerative lumbar disease between January 2009 and October 2009, a total of 50 patients with ASD after surgery were selected. Another group of 50 matched patients with degenerative lumbar disease without ASD after spinal fusion were selected as the control group. Each patient in the ASD group was matched with a control patient according to age, sex, fusion level, and follow-up period. OUTCOME MEASURES: Radiographic measurements and demographic data were reviewed. METHODS: The risk factors considered were higher BMI, preoperative adjacent segment disc and facet degeneration, and preoperative paraspinal muscle atrophy and fatty degeneration. The radiographic data were compared between the ASD and control groups to determine the predictive factors of ASD after posterior lumbar fusion by using logistic regression analysis. The study was not externally funded. The authors have no conflict of interest to declare. RESULTS: Multivariate logistic regression analysis indicated that higher BMI (odds ratio [OR]: 1.353, p=.008), preoperative facet degeneration on computed tomography examination (OR: 3.075, p=.011), disc degeneration on magnetic resonance imaging (MRI) (OR: 2.783, p=.003), fatty degeneration (OR: 1.080, p=.044), and a smaller relative CSA of the paraspinal muscle preoperatively (OR: 0.083, p=.003) were significant factors for predicting the development of ASD. CONCLUSIONS: The occurrence of radiological ASD is most likely multifactorial, and is associated with a higher BMI, preexisting facet and disc degeneration on preoperative examination, and a smaller preoperative relative CSA of the paraspinal muscle on MRI.

Bone Mineral Density Changes after Orchiectomy using a Scrotal Approach in Rats.

OBJECTIVE: To investigate a suitable animal model for studies of male osteoporosis. Osteoporosis has a particularly high incidence in postmenopausal women, resulting in a substantial amount of research with respect to this disease in women. However, research on osteoporosis in men is still lacking. METHODS: Twenty 10-week-old male Sprague Dawley rats were used in this study, including 4 rats used to establish a baseline bone mineral density (BMD). The other 16 rats were divided into two groups: a sham surgery group (n=8), which underwent a sham operation, and an orchiectomized rat group (OCX) (n=8), which underwent bilateral OCX at 10 weeks of age. Bone mineral density was measured in 4 rats from both the sham surgery group and the OCX group 8 weeks after the surgery, while BMD in the remainder of the rats was measured 10 weeks post-surgery. RESULTS: Femoral BMD at 8 weeks post-surgery was found to be significantly lower in the OCX group compared to the sham group; a finding that was also similar 10 weeks post-surgery. CONCLUSION: 8 weeks after undergoing orchiectomy performed via a scrotal, white rats are a suitable model for studies of male osteoporosis.

Anti-platelet drug resistance in the prediction of thromboembolic complications after neurointervention.

OBJECTIVE: The aim of this study was to analyze the correlation between thromboembolic complications and antiplatelet drugs before and after neurointervention. METHODS: Blood samples and radiographic data of patients who received a neurointervention (coil embolization, stent placement or both) were collected prospectively. Rapid platelet function assay-aspirin (RPFA-ASA) was used to calculate aspirin resistance in aspirin reaction units (ARU). For clopidogrel resistance, a P2Y12 assay was used to analyze the percentage of platelet inhibition. ARU > 550 and platelet inhibition < 40% were defined as aspirin and clopidogrel resistance, respectively. RESULTS: Both aspirin and clopidogrel oral pills were administered in fifty-three patients before and after neurointerventional procedures. The mean resistance values of all patients were 484 ARU and < 39%. Ten (17.0%) of 53 patients showed resistance to aspirin with an average of 597 ARU, and 33 (62.3%) of 53 patients showed resistance to clopidogrel with an average of < 26%. Ten patients demonstrated resistance to both drugs, 5 of which suffered a thromboembolic complication after neurointervention (mean values : 640 ARU and platelet inhibition < 23%). Diabetic patients and patients with hypercholesterolemia displayed mean aspirin resistances of 513.7 and 501.8 ARU, and mean clopidogrel resistances of < 33.8% and < 40.7%, respectively. CONCLUSION: Identifying individuals with poor platelet inhibition using standard regimens is of great clinical importance and may help prevent cerebral ischemic events in the future. Neurointerventional research should focus on ideal doses, timing, choices, safety, and reliable measurements of antiplatelet drug therapy, as well as confirming the clinical relevance of aggregometry in cerebrovascular patients.