The Validation of the Japanese Version of the Scoliosis Research Society-30 Questionnaire for Adolescent Idiopathic Scoliosis Patients.

Introduction: The Scoliosis Research Society-30 (SRS-30) is a questionnaire originally developed from the SRS-22r questionnaire and is used to evaluate adolescent idiopathic scoliosis (AIS). It comprised questions on five domains: function, pain, self-image, mental health, and satisfaction, with seven additional questions related to postoperative aspects. In addition to the original English version, translations in multiple languages have been effectively applied. Herein, we evaluated the internal consistency and external validity of the Japanese version of the SRS-30 for AIS patients. Methods: Among the 30 questions in SRS-30, the eight additional questions from SRS-22r were translated and back-translated to create a Japanese version of the SRS-30. This translated questionnaire was then used to survey patients with AIS who underwent corrective fusion surgery one year postoperatively. The internal consistency of the responses was evaluated using the Cronbach α coefficient. Additionally, the Spearman correlation analyses were conducted to assess the correlation between the scores obtained from the SRS-30 Japanese version and SRS-22r and the Oswestry Disability Index (ODI) for the overall scale and the five domains. Results: A total of 81 cases (eight males and 73 females; mean age at surgery 14.4 years) were enrolled. The mean preoperative Cobb angle was 51.0°. The Cronbach α coefficient for the overall SRS-30 was 0.861, indicating high internal consistency, while the coefficients for each domain were as follows: function/activity, 0.697; pain, 0.405; self-image/appearance, 0.776; mental health, 0.845; and satisfaction, 0.559. The SRS-30 total score significantly correlated with the SRS-22r total (r=0.945, P<0.001) and the ODI (r=-0.511, P<0.001). The SRS-30 domains highly correlated with the corresponding SRS-22r domains, with correlations ranging from r=0.826 to 0.901 (all P<0.001). Conclusions: The Japanese version of the SRS-30 demonstrated good internal and external validity. The SRS-30 can be used as an assessment tool for health-related quality of life in AIS patients.

Motion Capture-based 3-dimensional Measurement of Range of Motion in Patients Undergoing Cervical Laminoplasty.

STUDY DESIGN: A prospective study. OBJECTIVE: To measure 3-dimensional cervical range of motion (ROM) by noninvasive optical tracking-based motion-capture technology in patients undergoing laminoplasty, and to elucidate the postoperative effects of laminoplasty on cervical mobility. SUMMARY OF BACKGROUND DATA: Cervical laminoplasty is a motion-sparing decompression surgery for degenerative cervical myelopathy. Unlike cervical laminectomy and fusion, the true postoperative impact of laminoplasty on neck motion has not been well studied. METHODS: Participants comprised 25 patients undergoing double-door cervical laminoplasty for degenerative cervical myelopathy in a single center. Maximum flexion/extension, left/right rotation, and left/right side bending were recorded using the motion-capture device preoperatively and 3 months postoperatively. ROMs in 3 orthogonal axes were calculated. Preoperative differences in C2-7 Cobb angles on lateral flexion/extension x-rays were also measured as the radiologic ROM to assess reliability. Preoperative and 1-year postoperative Japanese Orthopaedic Association score, Neck Disability Index [NDI], and Euro-QOL were recorded, and correlations with ROMs were assessed. RESULTS: Preoperative mean (±SD) ROMs for flexion/extension, rotation, and side bending were 90±17, 107±16, and 53±17 degrees, respectively. Although radiologic sagittal ROM measurement showed a smaller range than motion capture, averaging 36±13 degrees, a moderate to strong correlation between radiologic and motion capture values was observed (R=0.57, P=0.003). Preoperative NDI showed a negative correlation with coronal ROM (rho=-0.547, P=0.02). Postoperative ROM showed a significant reduction in rotation (95±16 degrees, P=0.002) but not in flexion/extension or side bending. CONCLUSIONS: Three-dimensional motion-capture analysis allowed reliable measurement of cervical ROM. Rotational ROM was significantly reduced after laminoplasty, showing that cervical kinematics are still significantly altered.

Postoperative Complications of Surgery for Cervical Spondylotic Myelopathy with and Without Athetoid Cerebral Palsy.

STUDY DESIGN: Retrospective cohort study. OBJECTIVES: With the aging of the Japanese population, patients with athetoid cerebral palsy (ACP) are getting older, and the rate of surgery for CSM is increasing in ACP patients. However, postoperative complications of such surgery among adult patients with ACP have not been reported yet. We investigated postoperative complications of surgery for CSM with ACP and compared them with those of surgery for CSM without ACP using a national inpatient database of Japan. METHODS: Using the Diagnosis Procedure Combination database, we identified 61382 patients who underwent surgery for CSM from July 2010 to March 2018. We examined patient backgrounds, surgical procedures, and type of hospital, and a 4:1 propensity score matching was performed to compare the outcomes between the non-ACP and ACP groups. RESULTS: There were 60 847 patients without ACP and 535 patients with ACP. The mean age was 68.5 years in the non-ACP group and 55 years in the ACP group. The percentages of patients who underwent fusion surgery were 21.6% and 68.8% in the non-ACP and ACP groups, respectively. The 4:1 propensity score matching selected 1858 in the non-ACP group and 465 in the ACP group. The ACP group was more likely to have postoperative urinary tract infection (.4% vs 2.8%, P < .001), postoperative pneumonia (.4% vs 2.4%, P < .001), and 90-day readmission for reoperation (1.9% vs 4.3%, P = .003). CONCLUSIONS: We found that ACP patients were more vulnerable to postoperative complications and reoperation after CSM than non-ACP patients.

Patients with a large ossification of the posterior longitudinal ligament have a higher incidence of arteriosclerosis in the carotid artery.

PURPOSE: This study aimed to investigate the impact of the severity of cervical ossification of the posterior longitudinal ligament (OPLL) on the incidence of arteriosclerosis in the carotid artery. METHODS: Patients with OPLL-induced cervical myelopathy were prospectively enrolled. The study involved analyzing patient characteristics, blood samples, computed tomography scans of the spine, and intima-media thickness (IMT) measurements of the common carotid artery. Patients were divided into two groups based on the size of the cervical OPLL to compare demographic data, comorbidities, and the presence of thickening of the carotid intima-media (max IMT ≥ 1.1 mm). RESULTS: The study included 96 patients (mean age: 63.5 years; mean body mass index: 26.9 kg/m2; 71.8% male; 35.4% with diabetes mellitus). The mean maximum anteroposterior (AP) diameter of the OPLL was 4.9 mm, with a mean occupancy ratio of 43%. The mean maximum IMT was 1.23 mm. Arteriosclerosis of the carotid artery was diagnosed in 62.5% of the patients. On comparing the two groups based on OPLL size, the group with larger OPLL (≥ 5 mm) had a higher BMI and a greater prevalence of carotid intima-media thickening. This significant difference in the prevalence of carotid intima-media thickening persisted even after adjusting for patient backgrounds using propensity score matching. CONCLUSIONS: Patients with a larger cervical OPLL showed a higher frequency of intima-media thickening in the carotid artery.

Bone Turnover Markers in Patients With Ossification of the Posterior Longitudinal Ligament in the Thoracic Spine.

STUDY DESIGN: A prospective, single-center, observational study. OBJECTIVE: To explore the association between serum levels of bone turnover markers and ossification of the posterior longitudinal ligament (OPLL) in the thoracic spine. SUMMARY OF BACKGROUND DATA: The relationship between bone turnover markers, such as N-terminal propeptide of type I procollagen (PINP) or tartrate-resistant acid phosphate 5b (TRACP-5b), and OPLL has previously been examined. However, the correlation between these markers and thoracic OPLL, which is more severe than cervical-only OPLL, remains unclear. METHODS: This prospective study included 212 patients from a single institution with compressive spinal myelopathy and divided them into those without OPLL (Non-OPLL group, 73 patients) and those with OPLL (OPLL group, 139 patients). The OPLL group was further subdivided into cervical OPLL (C-OPLL, 92 patients) and thoracic OPLL (T-OPLL, 47 patients) groups. Patients' characteristics and biomarkers related to bone metabolism, such as calcium, inorganic phosphate (Pi), 25-hydroxyvitamin D, 1α,25 dihydroxyvitamin D, PINP, and TRACP-5b, were compared between the Non-OPLL and OPLL groups, as well as the C-OPLL and T-OPLL groups. Bone metabolism biomarkers were also compared after adjusting for age, sex, body mass index, and the presence of renal impairment using propensity score-matched analysis. RESULTS: The OPLL group had significantly lower serum levels of Pi and higher levels of PINP versus the Non-OPLL group as determined by propensity score-matched analysis. The comparison results between the C-OPLL and T-OPLL groups using a propensity score-matched analysis showed that T-OPLL patients had significantly higher concentrations of bone turnover markers, such as PINP and TRACP-5b, compared with C-OPLL patients. CONCLUSIONS: Increased systemic bone turnover may be associated with the presence of OPLL in the thoracic spine, and bone turnover markers such as PINP and TRACP-5b can help screen for thoracic OPLL.

Reliability and head-loading effects in imaging diagnosis of vertical subluxation in patients with rheumatoid arthritis.

OBJECTIVES: The purpose of this study was to examine the reproducibility of vertical subluxation (VS) parameters using X-ray, computed tomography (CT), and tomosynthesis (TS) while comparing the head-loading effects. METHODS: The VS parameters of 26 patients (retrospective review) were evaluated. Using the intra-class correlation coefficient, we statistically examined the intra-rater and inter-rater reliabilities of the parameters. Head-loaded and -unloaded imagings were compared using a Wilcoxon signed-rank test. RESULTS: The intra-rater reliability of TS and CT showed intra-class correlation coefficients of ≥0.8 (X-ray range: 0.6-0.8), with similar results for the inter-rater reliabilities. Furthermore, in head-loading imaging, the TS had significantly higher VS scores than that of CT (P < .05). CONCLUSIONS: In comparison with the X-ray, TS and CT were more accurate and reproducible. In terms of head loading, the VS values for TS were worse than those for CT, indicating that TS was more effective than CT in diagnosing VS.

Does surgical site infection affect patient-reported outcomes after spinal surgery? A multicenter cohort study.

BACKGROUND: Surgical site infections are common in spinal surgeries. It is uncertain whether outcomes in spine surgery patients with vs. without surgical site infection are equivalent. Therefore, we assessed the effects of surgical site infection on postoperative patient-reported outcomes. METHODS: We enrolled patients who underwent elective spine surgery at 12 hospitals between April 2017 and February 2020. We collected data regarding the patients' backgrounds, operative factors, and incidence of surgical site infection. Data for patient-reported outcomes, namely numerical rating scale, Neck Disability Index/Oswestry Disability Index, EuroQol Five-Dimensional questionnaire, and 12-Item Short-Form Health Survey scores, were obtained preoperatively and 1 year postoperatively. We divided the patients into with and without surgical site infection groups. Multivariate logistic regression analyses were performed to identify the risk factors for surgical site infection. Using propensity score matching, we obtained matched surgical site infection-negative and -positive groups. Student's t-test was used for comparisons of continuous variables, and Pearson's chi-square test was used to compare categorical variables between the two matched groups and two unmatched groups. RESULTS: We enrolled 8861 patients in this study; 74 (0.8 %) developed surgical site infections. Cervical spine surgery and American Society of Anesthesiologists physical status classification ≥3 were identified as risk factors; microendoscopy was identified as a protective factor. Using propensity score matching, we compared surgical site infection-positive and -negative groups (74 in each group). No significant difference was found in postoperative pain or dysesthesia of the lower back, buttock, leg, and plantar area between the groups. When comparing preoperative with postoperative pain and dysesthesia, statistically significant improvement was observed for both variables in both groups (p < 0.01 for all variables). No significant differences were observed in postoperative outcomes between the matched surgical site infection-positive and -negative groups. CONCLUSIONS: Patients with surgical site infections had comparable postoperative outcomes to those without surgical site infections.

Reduced volume and altered composition of paraspinal muscles in Marfan syndrome: A retrospective cohort study.

Retrospective cohort study. Spinal deformities in patients with Marfan syndrome (MFS) are distinct from those in patients with idiopathic scoliosis (IS). It is more prone to progression and more likely to present with sagittal malalignment than IS. However, the etiology of this characteristic spinal deformity in MFS remains unclear. This study aimed to determine the spinal musculature characteristics in patients with MFS on the hypothesis that the paraspinal muscles of patients with MFS would be qualitatively or quantitatively different from those of patients with IS. Seventeen consecutive patients with MFS aged 25 years or younger undergoing surgery for scoliosis in our hospital were compared with age- and sex-matched patients with IS undergoing surgery for scoliosis. The body size-adjusted relative cross-sectional area (rCSA), fatty infiltration ratio (FI%), and relative functional cross-sectional area (rFCSA) of the psoas muscles (PM) and paravertebral muscles (PVM) at L3/4 and L4/5 were measured using preoperative T2-weighted magnetic resonance imaging. Functional CSA was defined as total CSA minus the fatty infiltration area of each muscle and rFCSA was calculated as the body size-adjusted functional CSA. The rCSA of the PM at L3/4 and L4/5 was significantly smaller in the MFS group than in the IS group (L3/4, P = .021; L4/5, P = .002). The FI% of the PM at L4/5 was significantly higher in the MFS group (P = .044). Consequently, the rFCSA of the PM at L3/4 and L4/5 and the rFCSA of the PVM at L3/4 in the MFS group were significantly smaller than those in the IS group (PM at L3/4, P = .021; PM at L4/5, P = .001; PVM at L3/4, P = .025). Compared with patients with IS, patients with MFS exhibited significantly decreased body-size-adjusted CSA of the PM and reduced body-size-adjusted functional CSA of the PVM and PM. These findings may partially explain the characteristics of distinctive spinal deformities in patients with MFS.

A Novel Screening Method for Scoliosis Using a Bodysuit and 3-Dimensional Imaging.

STUDY DESIGN: A single-center prospective observational study. OBJECTIVE: To clarify the usefulness of a novel scoliosis screening method using a 3-dimensional (3D) human fitting application and a specific bodysuit. SUMMARY OF BACKGROUND DATA: Several scoliosis screening methods, such as scoliometer and Moiré topography, are available for detecting scoliosis. In the present study, a novel screening method for scoliosis using a 3D human fitting application and a specific bodysuit was developed. PATIENTS AND METHODS: Patients with scoliosis or suspected scoliosis, patients with non-scoliosis, and healthy volunteers were enrolled. They were divided into "non-scoliosis" and "scoliosis" groups. The scoliosis group was further subdivided into "mild," "moderate," and "severe-scoliosis" groups. Patients' characteristics and Z values, which were calculated by a 3D virtual human body model created by a 3D human fitting application and a specific bodysuit to evaluate trunk asymmetry caused by scoliosis, were compared between the non-scoliosis and scoliosis groups or among the non, mild, moderate and severe-scoliosis groups. Finally, the optimal cutoff of the Z value was determined to detect moderate to severe scoliosis using receiver operating characteristic curve analysis. RESULTS: A total of 101 patients were included. The non-scoliosis group consisted of 47 patients, and the scoliosis group included 54 patients, with 11, 31, and 12 patients in the mild, moderate, and severe-scoliosis groups, respectively. The scoliosis group showed a significantly higher Z value than the non-scoliosis group. The moderate or severe-scoliosis group had a significantly higher Z value than the non or mild-scoliosis group. The receiver operating characteristic curve analysis revealed that the optimal cutoff of the Z value was 19.9 mm (sensitivity, 95.3% and specificity, 58.6%). CONCLUSION: A novel scoliosis screening method consisting of a 3D human fitting application and a specific bodysuit may be useful for detecting moderate to severe scoliosis.

Adaptation and Limitations of painDETECT Questionnaire Score Approach Before and After Posterior Cervical Decompression Surgery.

BACKGROUND: The painDETECT questionnaire (PDQ) is one of the available screening tools for neuropathic pain (NeP), with a cut-off score of 13. This study aimed to investigate changes in PDQ scores in patients undergoing posterior cervical decompression surgery for degenerative cervical myelopathy (DCM). METHODS: Patients with DCM undergoing cervical laminoplasty or laminectomy with posterior fusion were recruited. They were asked to complete a booklet questionnaire including PDQ and Numerical Rating Scales (NRS) for pain at baseline and one year after surgery. Patients with a preoperative PDQ score ≥13 were further investigated. RESULTS: A total of 131 patients (mean age = 70.1 years; 77 male and 54 female) were analyzed. After posterior cervical decompression surgery for DCM, mean PDQ scores decreased from 8.93 to 7.28 (P = 0.008) in all patients. Of the 35 patients (27%) with preoperative PDQ scores ≥13, mean PDQ changed from 18.83 to 12.09 (P < 0.001). Comparing the NeP improved group (17 patients with postoperative PDQ scores ≤12) with the NeP residual group (18 patients with postoperative PDQ scores ≥13), the NeP improved group showed less preoperative neck pain (2.8 vs. 4.4, P = 0.043) compared to the NeP residual group. There was no difference in the postoperative satisfaction rate between the two groups. CONCLUSIONS: Approximately 30% of patients exhibited preoperative PDQ scores ≥13, and about half of these patients demonstrated improvements to below to the cut-off value for NeP after posterior cervical decompression surgery. The PDQ score change was relatively associated with preoperative neck pain.

Impact of body mass index on outcomes after lumbar spine surgery.

The impact of body mass index (BMI) on outcomes after lumbar spine surgery is currently unknown. Previous studies have reported conflicting evidence for patients with high BMI, while little research has been conducted on outcomes for underweight patients. This study aims to examine the impact of BMI on outcomes after lumbar spine surgery. This prospective cohort study enrolled 5622 patients; of which, 194, 5027, and 401 were in the low (< 18.5 kg/m2), normal (18.5-30), and high (≥ 30) BMI groups, respectively. Pain was assessed via the numerical pain rating scale (NPRS) for the lower back, buttock, leg, and plantar area. Quality of life was assessed via the EuroQol 5 Dimension (EQ-5D) and Oswestry Disability Index (ODI). Inverse probability weighting with propensity scores was used to adjust patient demographics and clinical characteristics between the groups. After adjustment, the 1-year postoperative scores differed significantly between groups in terms of leg pain. The proportion of patients who achieved a 50% decrease in postoperative NPRS score for leg pain was also significantly different. Obese patients reported less improvement in leg pain after lumbar spine surgery. The outcomes of patients with low BMI were not inferior to those of patients with normal BMI.

Predictors for hemostatic thrombin-gelatin matrix usage in spine surgery: a multicenter observational study.

STUDY DESIGN: A prospective cohort study. OBJECTIVES: Thrombin-gelatin matrix (TGM) is a rapid and potent hemostatic agent, but it has some limitations, including the cost and its preparation time. The purpose of this study was to investigate the current trend in the use of TGM and to identify the predictors for TGM usage in order to ensure its proper use and optimized resource allocation. METHODS: A total of 5520 patients who underwent spine surgery in a multicenter study group within a year were included in the study. The demographic factors and the surgical factors including spinal levels operated, emergency surgery, reoperation, approach, durotomy, instrumented fixation, interbody fusion, osteotomy, and microendoscopy-assistance were investigated. TGM usage and whether it was routine or unplanned use for uncontrolled bleeding were also checked. A multivariate logistic regression analysis was used to identify predictors for unplanned use of TGM. RESULTS: Intraoperative TGM was used in 1934 cases (35.0%), among which 714 were unplanned (12.9%). Predictors of unplanned TGM use were female gender (adjusted odds ratio [OR]: 1.21, 95% confidence interval [CI]: 1.02-1.43, p = 0.03), ASA grade ≥ 2 (OR: 1.34, 95% CI: 1.04-1.72, p = 0.02), cervical spine (OR: 1.55, 95% CI: 1.24-1.94, p < 0.001), tumor (OR: 2.02, 95% CI: 1.34-3.03, p < 0.001), posterior approach (OR: 1.66, 95% CI: 1.26-2.18, p < 0.001), durotomy (OR: 1.65, 95% CI: 1.24-2.20, p < 0.001), instrumentation (OR: 1.30, 1.03-1.63, p = 0.02), osteotomy (OR: 5.00, 2.76-9.05, p < 0.001), and microendoscopy (OR: 2.24, 1.84-2.73, p < 0.001). CONCLUSIONS: Many of the predictors for unplanned TGM use have been previously reported as risk factors for intraoperative massive hemorrhaging and blood transfusion. However, other newly revealed factors can be predictors of bleeding that is technically challenging to control. While routine usage of TGM in these cases will require further justification, these novel findings are valuable for implementing preoperative precautions and optimizing resource allocation.

Effect of Early Postoperative Resolution of MRI Signal Intensity Changes on the Outcomes of Degenerative Cervical Myelopathy.

STUDY DESIGN: A retrospective cohort study. OBJECTIVE: To investigate whether the timing of postoperative resolution of increased signal intensity (ISI) in the spinal cord is associated with surgical outcomes. SUMMARY OF BACKGROUND DATA: It remains unclear whether changes in ISI in the early postoperative period influence surgical outcomes. METHODS: This retrospective cohort study evaluated consecutive patients undergoing surgery for degenerative cervical myelopathy at a single academic hospital between January 2012 and September 2019. These patients underwent magnetic resonance imaging (MRI) preoperatively, within two weeks postoperatively (early MRI) and after six months postoperatively (late MRI). ISI was classified as follows: grade 0, none; grade 1, light (obscure); and grade 2, intense (bright). Patients were categorized into the following three groups: those with postoperative ISI resolution at early MRI (group E) or only at the late MRI (group L) stage and those whose ISI was persistent (group P). The surgical outcomes were compared between these three groups. RESULTS: We included 204 patients with complete data eligible for the analysis, and 163 of them had preoperative ISI. Postoperative ISI regression was observed in 49 (30.1%) patients. Of these 49 patients, 25 showed ISI resolution at early MRI (group E) and 24 only at late MRI (group L). All 49 were grade 1 on preoperative MRI, and this was not found to significantly impact surgical outcomes. In comparing surgical outcomes between the groups, group E had better postoperative Japanese Orthopedic Association scores and Japanese Orthopedic Association recovery rates than groups L and P. No significant differences were observed between groups L and P. CONCLUSIONS: Early resolution of preoperative grade 1 ISI on postoperative T2-weighted MRI may be associated with better surgical outcomes in patients with degenerative cervical myelopathy undergoing cervical spinal surgery.

Noninvasive Skin Autofluorescence of Advanced Glycation End Products for Detecting Ossification of the Posterior Longitudinal Ligament in the Thoracic Spine.

STUDY DESIGN: A single-center prospective observational study. OBJECTIVE: The aim was to clarify the usefulness of assessing advanced glycation end products (AGEs) by noninvasive skin autofluorescence in patients with ossification of the posterior longitudinal ligament (OPLL). SUMMARY OF BACKGROUND DATA: AGE accumulation is associated with various systemic disorders, including aging, diabetes mellitus, and obesity. AGEs have also been associated with OPLL, but their assessment by noninvasive skin autofluorescence has not been yet studied in these patients. MATERIALS AND METHODS: We enrolled patients with degenerative spinal spondylosis and divided them into non-OPLL and OPLL groups. The OPLL group was further subdivided into cervical OPLL (C-OPLL) and thoracic OPLL (T-OPLL) groups. We compared patients' characteristics, serum laboratory data (i.e. hemoglobin A1c, total cholesterol, creatinine, and estimated glomerular filtration rate), and the skin autofluorescence intensity of AGEs (the AGE score) between the non-OPLL and OPLL groups and among the non-OPLL, C-OPLL, T-OPLL groups. Finally, the association of the AGE score with the presence of C-OPLL or T-OPLL was assessed by multinomial logistic regression. RESULTS: Among the 240 eligible patients, 102 were in the non-OPLL group and 138 were in the OPLL group (92 with C-OPLL and 46 with T-OPLL). We observed no significant difference in the AGE score between the non-OPLL and OPLL groups, but when comparing the score among the non-OPLL, C-OPLL, and T-OPLL groups, we found that the T-OPLL group had a significantly higher AGE score. The results of multinomial regression analysis showed that a higher AGE score was significantly associated with T-OPLL (odds ratio: 1.46; 95% CI: 1.01-2.11; P=0.044). CONCLUSION: The AGE score determined by noninvasive skin autofluorescence could help to screen for OPLL in the thoracic spine.

Impact of pathogenic FBN1 variant types on the development of severe scoliosis in patients with Marfan syndrome.

BACKGROUND: Among the several musculoskeletal manifestations in patients with Marfan syndrome, spinal deformity causes pain and respiratory impairment and is a great hindrance to patients' daily activities. The present study elucidates the genetic risk factors for the development of severe scoliosis in patients with Marfan syndrome. METHODS: We retrospectively evaluated 278 patients with pathogenic or likely pathogenic FBN1 variants. The patients were divided into those with (n=57) or without (n=221) severe scoliosis. Severe scoliosis was defined as (1) patients undergoing surgery before 50 years of age or (2) patients with a Cobb angle exceeding 50° before 50 years of age. The variants were classified as protein-truncating variants (PTVs), which included variants creating premature termination codons and inframe exon-skipping, or non-PTVs, based on their location and predicted amino acid alterations, and the effect of the FBN1 genotype on the development of severe scoliosis was examined. The impact of location of FBN1 variants on the development of severe scoliosis was also investigated. RESULTS: Univariate and multivariate analyses revealed that female sex, PTVs of FBN1 and variants in the neonatal region (exons 25-33) were all independent significant predictive factors for the development of severe scoliosis. Furthermore, these factors were identified as predictors of progression of existing scoliosis into severe state. CONCLUSIONS: We elucidated the genetic risk factors for the development of severe scoliosis in patients with Marfan syndrome. Patients harbouring pathogenic FBN1 variants with these genetic risk factors should be monitored carefully for scoliosis progression.

Association Between Deep Posterior Cervical Paraspinal Muscle Morphology and Clinical Features in Patients With Cervical Ossification of the Posterior Longitudinal Ligament.

STUDY DESIGN: A retrospective observational study. OBJECTIVE: To clarify the association of the paraspinal muscle area and composition with clinical features in patients with cervical ossification of the posterior longitudinal ligament (OPLL). METHODS: Consecutive patients with cervical OPLL who underwent cervical magnetic resonance imaging (MRI) before surgery were reviewed. The cross-sectional area (CSA) and fatty infiltration ratio (FI%) of deep posterior cervical paraspinal muscles (multifidus [MF] and semispinalis cervicis [SCer]) were examined. We assessed the association of paraspinal muscle measurements with the clinical characteristics and clinical outcomes, such as Neck Disability Index (NDI) score. Moreover, we divided the patients into 2 groups according to the extent of the ossified lesion (segmental and localized [OPLL-SL] and continuous and mixed [OPLL-CM] groups) and compared these variables between the 2 groups. RESULTS: 49 patients with cervical OPLL were enrolled in this study. The FI% of the paraspinal muscles was significantly associated with the number of vertebrae (ρ = 0.283, p = 0.049) or maximum occupancy ratio of OPLL (ρ = 0.397, p = 0.005). The comparative study results indicated that the NDI score was significantly worse (OPLL-SL, 22.9 ± 13.7 vs. OPLL-CM, 34.4 ± 13.7) and FI% of SCer higher (OPLL-SL, 9.1 ± 1.7% vs. OPLL-CM, 11.1 ± 3.7%) in the OPLL-CM group than those in the OPLL-SL group. CONCLUSIONS: Our results suggest that OPLL severity may be associated with fatty infiltration of deep posterior cervical paraspinal muscles, which could affect neck disability in patients with cervical OPLL.

Does Surgical Treatment Affect the Degree of Anxiety or Depression in Patients With Degenerative Cervical Myelopathy?

STUDY DESIGN: Retrospective cohort study. OBJECTIVES: Preoperative mental state has been reported as one of the factors affecting the surgical outcomes of spine surgery, but few studies have examined in detail how patients' mental state is affected by spine surgery. The purpose of this study was to investigate using the Hospital Anxiety and Depression Scale (HADS) whether surgery improves preoperative depression and anxiety in patients with degenerative cervical myelopathy. METHODS: We investigated patient-reported outcomes (Mental Component Summary, Physical Component Summary of SF-12 Health Survey, and EQ-5D, Neck Disability Index, JOACMEQ, satisfaction with treatment) and HADS one year after surgery, comparing them before and after surgery between April 2017 and February 2020. Among the cases diagnosed as preoperative anxiety and depression, we additionally compared the patient-reported outcomes based on the presence or absence of postoperative improvement in mental state, having also investigated the correlation between patient-reported outcomes and HADS for sub-analysis. RESULTS: Among the 99 patients eligible for inclusion in the present study, we found that patient-reported outcomes and the HADS scores improved significantly after surgery. There was a moderate correlation between the amount of change in HADS-D score before and after surgery and the amount of change in NDI (moderate, r = .41), NRS of neck (moderate, r = .46), and JOACMEQ (cervical spine function; moderate, r = .43, upper extremity function; moderate, r = .41, QOL; moderate, r = .41). CONCLUSIONS: We found that surgical treatment for patients with degenerative cervical myelopathy may improve postoperative anxiety and depression as well as other patient-reported outcomes.

A dynamic pedicle screw system using polyethylene insert for the lumbar spine.

Rigid spinal fusion with instrumentation has been widely applied in treating degenerative spinal disorders and has shown excellent and stable surgical results. However, adjacent segment pathology or implants' loosening could be problematic due to the spine's segmental fusion. Therefore, this study verified a novel concept for posterior stabilization with polyethylene inserts inside a pedicle screw assembly using bone models. We observed that although the gripping capacity of the dynamic pedicle screw system using a tensile and compression tester was less than half that of the rigid pedicle screw system, the flexion-extension moment of the dynamic pedicle screws was significantly lower than that of the rigid pedicle screws. Furthermore, while the bending force of the rigid pedicle screw assembly increased linearly with an increase in the bending angle throughout the test, that of the dynamic pedicle screw assembly also increased linearly until a bending angle of 2.5° was reached. However, this angle decreased at a bending angle of more than 2.5°. Additionally, the fatigue test of 1.0 × 106 cycles showed that the pull-out force of the dynamic pedicle screws from two different polyurethane foam blocks was significantly higher than that of the rigid pedicle screws. Therefore, based on our results, we propose that the device can be applied in clinical cases to reduce screw loosening and adjacent segment pathology.

Surgical outcomes between posterior decompression alone and posterior decompression with fusion surgery among patients with Meyerding grade 2 degenerative spondylolisthesis: a multicenter cohort study.

BACKGROUND: Whether lumbar decompression with fusion surgery is effective against Meyerding grade 2 degenerative spondylolisthesis (DS) is unknown. Therefore, the current study aimed to compare the surgical outcomes between posterior decompression alone and posterior decompression with fusion surgery among patients with grade 2 DS with central canal stenosis. METHODS: This retrospective cohort study included prospectively registered patients (n = 3863) who underwent surgery for degenerative lumbar spinal canal stenosis at nine high-volume spine centers from April 2017 to July 2019. Patients with grade 2 DS and central canal stenosis were included in the analysis. Patients with radiculopathy, including foraminal stenosis, degenerative scoliosis, and concomitant anterior spinal fusion, and those with a previous history of lumbar surgery were excluded. The participants were divided into the decompression alone group (group D) and decompression with fusion surgery group (group F). Data about patient-reported outcomes, including Numeric Rating Scale (low back pain, leg pain, leg numbness, and foot numbness), Oswestry Disability Index, EuroQol Five-Dimensional questionnaire, and 12-Item Short-Form Health Survey scores, were obtained preoperatively and 2 years postoperatively. RESULTS: In total, 2354 (61%) patients, including 42 (1.8%) with grade 2 DS (n = 18 in group D and n = 24 in group F), completed the 2-year follow-up. Group D had a higher proportion of female patients than group F. However, the two groups did not significantly differ in terms of other baseline demographic characteristics. Group D had a significantly shorter surgical time and lower volume of intraoperative blood loss than group F. Postoperative patient-reported outcomes did not significantly differ between the two groups, although the preoperative degree of low back pain was higher in group F than in group D. The slip degree of group D did not worsen during the follow-up period. CONCLUSION: The surgical outcomes were similar regardless of the addition of fusion surgery among patients with grade 2 DS. Decompression alone was superior to decompression with fusion surgery as it was associated with a lower volume of intraoperative blood loss and shorter surgical time.

Clinical Feasibility of Completely Autologous Fibrin Glue in Spine Surgery.

Introduction: Fibrin glue is widely used in spine surgery. Nevertheless, no report has demonstrated the feasibility of completely autologous fibrin glue (CAFG) in spine surgery. This study aims to investigate the safety, efficacy, and effect of bone fusion of CAFG on spine surgery. Methods: We retrospectively extracted data of patients who underwent primary spine surgery with preoperatively prepared CAFG. Primary outcomes were the incidence of wound-related unplanned reoperations within 90 days following primary surgery and the occurrence of reoperation for the management of cerebrospinal fluid (CSF) leakage in patients who had been treated with CAFG used as dural sealants. The effect of CAFG on bone fusion was also assessed by detecting implant failure at one year postoperatively in patients aged 25 years or less undergoing primary fusion for idiopathic scoliosis. Results: We identified 131 eligible patients (47 males and 84 females) with a mean age of 32.3 years. CAFG was used most frequently as an adhesive for fixation of graft bone (110 patients), followed by as a dural sealant for CSF leakage in 17 patients, and as a local hemostatic agent in four patients. Wound-related reoperations were identified in four patients (3.1%), which included three for surgical site infection, and one for postoperative epidural hematoma. There was no reoperation required for the management of CSF leakage among 17 patients with dural incision or incidental durotomy. Compared with the control cohort, the use of CAFG was not associated with early wound-related reoperations or implant failure in patients with spinal deformity. Conclusions: We demonstrated the clinical feasibility of CAFG in spine surgery. The use of CAFG was not associated with the incidence of reoperations for wound-related complications. CAFG worked effectively as a dural sealant for preventing CSF leakage. CAFG had no beneficial or adverse effect on spinal bone fusion.