Surgical Treatment Outcomes of Anterior-Only Correction and Reconstruction for Severe Cervical Kyphotic Deformity with Neurofibromatosis-1: A Retrospective Study with a 5-Year Follow-Up.

OBJECTIVES: Currently, anterior-only (AO), posterior-only, and combined anterior-posterior spinal fusions are common strategies for treating cervical kyphosis in patients with neurofibromatosis-1 NF-1. Nevertheless, the choice of surgical strategy remains a topic of controversy. The aim of our study is to evaluate the safety and effectiveness of anterior decompression and spinal reconstruction for the treatment of cervical kyphosis in patients with NF-1. METHODS: Twelve patients with NF-1-associated cervical kyphotic deformity were reviewed retrospectively between January 2010 and April 2020. All patients underwent AO correction and reconstruction. The X-ray was followed up in all these patients to assess the preoperative and postoperative local kyphosis angle (LKA), the global kyphosis angle (GKA), the sagittal vertical axis, and the T1 slope. The visual analog scale score, Japanese Orthopedic Association (JOA) score, and neck disability index (NDI) score were used to evaluate the improvement inclinical symptoms. The results of the difference in improvement from preoperatively to the final follow-up assessment were assessed using a paired t-test or Mann-Whitney U-test. RESULTS: The LKA and GKA decreased from the preoperative average of 64.42 (range, 38-86) and 35.50 (range, 10-81) to an average of 16.83 (range, -2 to 46) and 4.25 (range, -22 to 39) postoperatively, respectively. The average correction rates of the LKA and GKA were 76.11% and 111.97%, respectively. All patients had achieved satisfactory relief of neurological symptoms (p < 0.01). JOA scores were improved from 10.42 (range, 8-16) preoperatively to 15.25 (range, 11-18) at final follow-up (p < 0.01). NDI scores were decreased from an average of 23.25 (range, 16-34) preoperatively to an average of 7.08 (range, 3-15) at the final follow-up (p < 0.01). CONCLUSION: Anterior-only correction and reconstruction is a safe and effective method for correcting cervical kyphosis in NF-1 patients. In fixed cervical kyphosis cases, preoperative skull traction should also be considered.

Two-level Anterior Cervical Corpectomy and Fusion versus Posterior Open-door Laminoplasty for the Treatment of Cervical Ossification of Posterior Longitudinal Ligament: A Comparison of the Clinical Impact on the Occipito-Atlantoaxial Complex.

OBJECTIVE: Both two-level anterior cervical corpectomy and fusion (t-ACCF) and posterior open-door laminoplasty (ODLP) are effective surgical procedures for the treatment of ossification of the posterior longitudinal ligament (OPLL). Previous studies have identified different effects of different surgical procedures on the upper and subaxial cervical spine (UCS, SCS), however, there are no studies on the effects of t-ACCF and ODLP on the occipito-atlantoaxial complex. Therefore, the purpose of this study is to compare the changes in sagittal parameters and range of motion (ROM) of the occipito-atlantoaxial complex in OPLL patients treated with t-ACCF and ODLP. METHODS: This was a retrospective study that included 74 patients who underwent t-ACCF or ODLP for the treatment of OPLL from January 2012 to August 2022 at our institution. Preoperative, 3-month, and 1-year postoperative cervical neutral, flexion-extension, and lateral flexion radiographs were taken. Sagittal parameters including Cobb angle of C2-7, C0-2, C0-1, C1-2, C2 slope, and the ROM were measured. The clinical outcome was assessed using the JOA, VAS, and NDI scores preoperatively and at 3 and 12 months postoperatively. Multiple linear regression was employed to identify factors influencing changes in UCS. RESULTS: In the ODLP group, the SCS (C2-7) Cobb angle was significantly reduced (12.85 ± 10.0 to 7.68 ± 11.27; p < 0.05), and the UCS (C0-2) Cobb angle was significantly compensated for at 1 year postoperatively compared with the t-ACCF group (3.05 ± 4.09 vs 0.79 ± 2.62; p < 0.01). The SCS and lateral flexion ROM of the ODLP group was better maintained than t-ACCF (14.51 ± 6.00 vs 10.72 ± 3.79; 6.87 ± 4.56 vs 3.81 ± 1.67; p < 0.01). The compensatory increase in C0-2, C0-1, and C1-2 ROM was pronounced in both groups, especially in the ODLP group. The results of multiple linear regression showed that only the surgical procedure was a significant factor influencing UCS. CONCLUSION: The loss of the SCS Cobb angle was more pronounced in ODLP relative to t-ACCF, resulting in a significant compensatory increase in UCS and atlantoaxial Cobb angle. The ROM of the UCS, atlantooccipital, and atlantoaxial joints was significantly increased in both groups, this may accelerate degenerative changes in the occipital-atlantoaxial complex, may leading to poorer outcomes in the long-term; of these, ODLP should receive more attention. In contrast, t-ACCF better maintains normal curvature of the SCS and occipito-atlantoaxial complex but loses more ROM.

[Current status of surgical treatment for angular kyphosis in spinal tuberculosis].

Objective: To review current status of surgical treatment for angular kyphosis in spinal tuberculosis and provide reference for clinical treatment. Methods: The literature on the surgical treatment for angular kyphosis of spinal tuberculosis in recent years was extensively reviewed and summarized from the aspects of surgical indications, surgical contraindications, surgical approach, selection of osteotomy, and perioperative management. Results: Angular kyphosis of spine is a common complication in patients with spinal tuberculosis. If kyphosis progresses gradually, it is easy to cause neurological damage, deterioration, and delayed paralysis, which requires surgical intervention. At present, surgical approaches for angular kyphosis of the spine include anterior approach, posterior approach, and combined anterior and posterior approaches. Anterior approach can be performed for patients with severe spinal cord compression and small kyphotic Cobb angle. Posterior approach can be used for patients with large kyphotic Cobb angle but not serious neurological impairment. A combined anterior and posterior approaches is an option for spinal canal decompression and orthosis. Osteotomy for kyphotic deformity include Smith-Peterson osteotomy (SPO), pedicle subtraction osteotomy (PSO), vertebral column resection(VCR), vertebral column decancellation (VCD), posterior vertebral column resection (PVCR), deformed complex vertebral osteotomy (DCVO), and Y-shaped osteotomy. SPO and PSO are osteotomy methods with relatively low surgical difficulty and low surgical risks, and can provide 15°-30° angular kyphosis correction effect. VCR or PVCR is a representative method of osteotomy and correction. The kyphosis correction can reach 50° and is suitable for patients with severe angular kyphosis. VCD, DCVO, and Y-shaped osteotomy are emerging surgical techniques in recent years. Compared with VCR, the surgical risks are lower and the treatment effects also improve to varying degrees. Postoperative recovery is also a very important part of the perioperative period and should be taken seriously. Conclusion: There is no consensus on the choice of surgical treatment for angular kyphosis in spinal tuberculosis. Osteotomy surgery are invasive, which is a problem that colleagues have always been concerned about. It is best to choose a surgical method with less trauma while ensuring the effectiveness.

S1 vertebral bone quality score independently predicts pedicle screw loosening following surgery in patients with adult degenerative scoliosis.

BACKGROUND CONTEXT: MRI-based vertebral bone quality (VBQ) score is an effective predictor of pedicle screw loosening after lumbar fusion surgery and has been recognized as a valuable tool for assessing preoperative bone quality. Due to the lateral curvature of lumbar spine of degenerative scoliosis, accurate measurement of VBQ score by conventional measurement methods that capture MRI signal intensity at L1-4 may be limited under certain conditions. To this end, a new simplified S1 VBQ score method has been proposed, which is comparable to the previous L1-4 VBQ score or S1 Hounsfield unit (HU) value, and has high accuracy and reliability. PURPOSE: To evaluate the predictive value of MRI-based S1 VBQ score for pedicle screw loosening following surgery for adult degenerative scoliosis (ADS). STUDY DESIGN/SETTING: Retrospective single-center cohort. PATIENT SAMPLE: We reviewed 92 patients who underwent posterior lumbar interbody fusion (PLIF) with pedicle screw fixation for ADS between January 2017 and January 2020. OUTCOME MEASURES: Association between S1 VBQ score and pedicle screw loosening following surgery for ADS. METHODS: We retrospectively reviewed the records of all patients who performed PLIF between January 2017 and January 2020. The clear zone around pedicle screws≥1 mm can be identified as screw loosening. The S1 VBQ score is calculated from the S1 central-based non-contrast T1-weighted magnetic resonance imaging (MRI). The signal intensity (SI) of the cerebrospinal fluid (CSF) was then measured using ROI placed at the L3 level to normalize the results. Multivariate logistic regression analysis was performed to identify independent risk factors for screw loosening. Then, constructed a receiver operating characteristic (ROC) curve and determined the threshold (cut-off) of VBQ score with high sensitivity and specificity based on Youden Index. RESULTS: A total of 92 patients were included, including 34 males and 58 females. The mean age of the patients was 61.23±1.23 years old. At 1-year follow-up, the screw loosening rate was 56.5% (52/92). The age and levels of fixation were higher in the loosening group than in the non-loosening group (p=.036, p=.025). Patients in the loosening group had a greater VBQ score compared to patients in the non-loosening group (3.31±0.41 vs 3.01±0.28, p=.001). Multivariate logistic regression analysis showed that advanced age (OR, 1.090; 95% CI 1.005-1.183; p=.039) and higher VBQ score (OR, 5.778; 95% CI 2.889-16.177; p=.001) were independent risk factors for screw loosening. In addition, the ROC curve were created to assess the role of VBQ score as predictors of screw loosening with a diagnostic accuracy of 74.6% (95% CI 64.2%-85.1%).The most suitable threshold for the VBQ score as determined by the Youden Index was 3.175 (sensitivity: 76.0%, specificity: 83.3%). CONCLUSIONS: Higher S1 VBQ score was significantly associated with pedicle screw loosening following surgery for ADS. The S1 VBQ score can be used as an effective preoperative predictor, which has the potential clinical application.

Simplified S1 vertebral bone quality score independently predicts proximal junctional kyphosis after surgery for degenerative lumbar scoliosis.

OBJECTIVE: Our study aimed to assess the effectiveness of the simplified S1 vertebral bone quality (VBQ) score in predicting the incidence of proximal junctional kyphosis (PJK) after surgery for degenerative lumbar scoliosis (DLS). METHODS: We reviewed 122 patients with DLS who underwent posterior lumbar decompression and long-segment fusion surgery in our hospital from January 2016 to December 2020. The patients were classified into PJK group and non-PJK group. S1 VBQ scores are determined by signal intensity measurements taken from the mid-sagittal plane of T1-weighted non-contrast MRI. Logistic regression analysis was used to identify factors associated with PJK. Receiver-operating characteristic curve (ROC) analysis was used to evaluate the value of S1 VBQ score in predicting pedicle PJK after DLS. RESULTS: 122 DLS patients (90 females and 32 males) met the inclusion criteria. In addition, 27 patients (22.13%) had PJK at the time of last follow-up. VBQ was higher in PJK patients than non-PJK patients (3.58 ± 0.67 vs. 3.08 ± 0.54, p < 0.001). Preoperatively, patients in the PJK group had a greater TLK than those in the non-PJK group (20.00 ± 6.22 vs. 16.86 ± 5.38, p = 0.011). After surgery, patients in the PJK group had greater TLK (p < 0.001) and PJA (p < 0.001) compared with the non-PJK group. At final FU, patients in the PJK group had greater TK (p = 0.002), TLK (p < 0.001), SVA (p < 0.001), and PJA (p < 0.001) than patients in the non-PJK group (Table 4). In multivariate logistic regression analysis, higher VBQ score (OR 4.565, 95% CI 1.43-14.568, p = 0.010), advanced age (OR 1.119, 95% CI 1.021-1.227, p = 0.016), and larger TLK (OR 1.191, 95% CI 1.041-1.362, p = 0.011) were significant predictors of postoperative PJK in patients with DLS (Table 6). A statistically significant positive correlation existed between VBQ score and PJA change (r = 0.370, p < 0.001). We created ROC curves for VBQ scores as predictors of PJK with a diagnostic accuracy of 72.1% (95% CI 60.15-82.9%.The ideal limit for the VBQ score was 3.205 (sensitivity: 77.8%, specificity: 81.4%). CONCLUSION: To the best of our knowledge, this is the first study to evaluate the effectiveness of the S1 VBQ score in predicting postoperative PJK in DLS. Our study included major risk factors and found that S1 VBQ score was a significant predictor of PJK in patients undergoing DLS surgery. The higher the S1 VBQ score, the higher the probability of PJK.

Long-term Outcome of Isobar TTL System for the Treatment of Lumbar Degenerative Disc Diseases.

OBJECTIVE: The Isobar TTL dynamic fixation system has demonstrated favorable outcomes in the short-term treatment of lumbar degenerative disc diseases (LDDs). However, there is a paucity of extensive research on the long-term effects of this system on LDDs. This study aimed to evaluate the long-term clinical and radiological outcomes of patients with LDDs who underwent treatment utilizing the Isobar TTL dynamic fixation system. METHODS: The study analyzed the outcomes of 40 patients with LDDs who underwent posterior lumbar decompression and received single-segment Isobar TTL dynamic internal fixation at our hospital between June 2010 and December 2016. The evaluation of clinical therapeutic effect involved assessing postoperative pain levels using the visual analogue scale (VAS) and Oswestry disability index (ODI), both before surgery, 3 months after, and the final follow-up. To determine the preservation of functional motion in dynamically stable segments, we measured the range of motion (ROM) and disc height of stabilized and adjacent segments preoperatively and during the final follow-up. Additionally, we investigated the occurrence of adjacent segment degeneration (ASD). RESULTS: Forty patients were evaluated, with an average age of 44.65 years and an average follow-up period of 79.37 months. Fourteen patients belonged to the spondylolisthesis group, while the remaining 26 were categorized under the stenosis or herniated disc group. The preoperative ROM of the stabilized segment exhibited a significant reduction from 8.15° ± 2.77° to 5.00° ± 1.82° at the final follow-up (p < 0.001). In contrast, there was a slight elevation in the ROM of the adjacent segment during the final follow-up, increasing from 7.68° ± 2.25° before surgery to 9.36° ± 1.98° (p < 0.001). The intervertebral space height (IH) in the stabilized segment exhibited a significant increase from 10.56 ± 1.99 mm before surgery to 11.39 ± 1.90 mm at the one-week postoperative follow-up (p < 0.001). Conversely, there was a notable decrease in the IH of the adjacent segment from 11.09 ± 1.82 mm preoperatively to 10.86 ± 1.79 mm at the one-week follow-up after surgery (p < 0.001). The incidence of ASD was 15% (6/40) after an average follow-up period of 79.37 months, with a rate of 15.38% (4/26) in the stenosis or herniated disc group and 14.29% (2/14) in the spondylolisthesis group; however, no statistically significant difference was observed in the occurrence of ASD among these groups (p > 0.05). CONCLUSION: The Isobar TTL dynamic fixation system is an effective treatment for LDDs, improving pain relief, quality of life (QoL) and maintaining stabilized segmental motion. It has demonstrated excellent long-term clinical and radiographic results.

Recent Advances in Nanotechnology-Based Strategies for Bone Tuberculosis Management.

Bone tuberculosis, an extrapulmonary manifestation of tuberculosis, presents unique treatment challenges, including its insidious onset and complex pathology. While advancements in anti-tubercular therapy have been made, the efficacy is often limited by difficulties in achieving targeted drug concentrations and avoiding systemic toxicity. The intricate bone structure and presence of granulomas further impede effective drug delivery. Nano-drug delivery systems have emerged as a promising alternative, offering the enhanced targeting of anti-tubercular drugs. These systems, characterized by their minute size and adaptable surface properties, can be tailored to improve drug solubility, stability, and bioavailability, while also responding to specific stimuli within the bone TB microenvironment for controlled drug release. Nano-drug delivery systems can encapsulate drugs for precise delivery to the infection site. A significant innovation is their integration with prosthetics or biomaterials, which aids in both drug delivery and bone reconstruction, addressing the infection and its osteological consequences. This review provides a comprehensive overview of the pathophysiology of bone tuberculosis and its current treatments, emphasizing their limitations. It then delves into the advancements in nano-drug delivery systems, discussing their design, functionality, and role in bone TB therapy. The review assesses their potential in preclinical research, particularly in targeted drug delivery, treatment efficacy, and a reduction of side effects. Finally, it highlights the transformative promise of nanotechnology in bone TB treatments and suggests future research directions in this evolving field.

Preoperative geriatric nutritional risk index is useful factor for predicting postoperative delirium among elderly patients with degenerative lumbar diseases.

PURPOSE: It is the first study to evaluate the predictive value of the geriatric nutritional risk index (GNRI) on postoperative delirium (POD) after transforaminal lumber interbody fusion (TLIF) in elderly patients with degenerative lumbar diseases. METHODS: A retrospective study was conducted to assess the outcomes of TLIF surgery in elderly patients with lumbar degenerative disease between the years 2016 and 2022. Delirium was diagnosed by reviewing postoperative medical records during hospitalization, utilizing the Confusion Assessment Method. The geriatric nutritional risk index was calculated using the baseline serum albumin level and body weight. Multivariate logistic regression analysis was employed to identify the association between preoperative GNRI and postoperative delirium (POD). Additionally, a receiver operating characteristic curve was utilized to determine the optimal GNRI cutoff for predicting POD. RESULTS: POD was observed in 50 of the 324 patients. The GNRI was visibly reduced in the delirium group. The mean GNRI was 93.0 ± 9.1 in non-delirium group and 101.2 ± 8.2 in delirium group. On multivariate logistic regression, Risk of POD increases significantly with low GNRI and was an independent factor in predicting POD following TLIF (OR 0.714; 95% CI 0.540-0.944; p = 0.018). On receiver operating characteristic curve, the area under curve (AUC) for GNRI was 0.738 (95% CI 0.660-0.817). The cutoff value for GNRI according to the Youden index was 96.370 (sensitivity: 66.0%, specificity: 70.4%). CONCLUSION: Our study indicated that lower GNRI correlated significantly with POD after TLIF. Performing GNRI evaluation prior to TLIF may be an effective approach of predicting the risk for POD among elderly patients with degenerative lumbar diseases.

The Comparison of Posterior Intervertebral Release Combined with Posterior Column Osteotomy and Posterior Column Osteotomy Alone for the Treatment of Moderate-to-Severe Rigid Scoliosis: A Prospective Controlled Study.

OBJECTIVES: There is no consensus on the treatment of moderate-to-severe rigid scoliosis. Anterior release and three-column osteotomy are excessively traumatic, whereas posterior column osteotomy (PCO) alone results in poor outcomes. An emerging surgical technique, posterior intervertebral release (PR), can release the rigid spine from the posterior approach. This study was performed to compare the multi-segment apical convex PR combined with PCO and PCO alone in patients with moderate-to-severe rigid scoliosis. METHODS: From June 2021 to June 2022, this prospective study of moderate-to-severe (Cobb: 70-90°) rigid scoliosis (flexibility of main curve <25%) involved two groups defined by surgical procedure: the PR group, the patients undergoing PR combined with PCO; and the PCO group, the patients undergoing PCO alone. Follow-up was at least 12 months. Radiographic results mainly included main curve Cobb, correction of per PR/PCO segment, apical vertebra rotation (AVR) and apical vertebra translation (AVT). Demographics, surgical data, complications were also recorded. Student's independent samples t test and Pearson's chi-square test were used to compare the differences between groups. RESULTS: Forty patients with an average age of 16.65 years were included (PR group, n = 20; PCO group, n = 20). The main curves averaged 77.56° ± 5.86° versus 78.02° ± 5.72° preoperatively and 20.07° ± 6.73° versus 33.58° ± 5.76° (p < 0.001) at the last follow-up in the PR and PCO groups, respectively. The mean correction rates were 74.30% and 56.84%, respectively (p < 0.001). The average coronal curve correction was 13.49° per release segment, which was significantly higher than the PCO correction of 6.20° (p < 0.001). The correction of apical vertebra rotation and translation in the main thoracic curve was significantly better in the PR group than in the PCO group (p < 0.05). Several minor complications in the two groups improved after conservative treatment. CONCLUSION: The multi-segment apical convex PR combined with PCO offers more advantages than PCO alone in the treatment of patients with moderate-to-severe rigid scoliosis. Owing to its excellent corrective effect and few complications, this is a high benefit-risk ratio surgical strategy for rigid scoliosis.

Health-related Quality of Life (HRQOL) Outcomes of Selective/Nonselective Thoracic Fusion for Lenke 1C Adolescent Idiopathic Scoliosis (AIS) Patients with a Minimum 4-year Follow-up.

OBJECTIVE: Both the selective thoracic fusion (STF) and nonselective thoracic fusion (NSTF) are treatments for Lenke 1C adolescent idiopathic scoliosis (AIS). To date, the impacts of the two surgical strategies on patients' long-term quality of life remain unclear. Therefore, the purpose of this study was to explore the long-term effects of STF/NSTF on the quality of life in Lenke 1C AIS patients through a 4-10-year follow-up. METHODS: From January 2011 to April 2018, according to the inclusion and exclusion criteria, a retrospective single-center study of 75 surgical patients with Lenke 1C curves was performed (n = 75). They all underwent posterior fusion, and patients were divided into the selective thoracic fusion (STF) group (n = 42) and the nonselective thoracic fusion (NSTF) group (n = 33) based on their surgical approach. All participants received the survey of the visual analogue scale (VAS), SRS30, SF12, and Oswestry disability index (ODI) scales. Patients' gender, age, body mass index (BMI), surgical approach (STF/NSTF), surgical segments (UIV and LIV), follow-up time, complications, preoperative, postoperative, and last follow-up Cobb angles, and health-related quality of life (HRQOL) outcomes were collected, and analyzed through the Shapiro-Wilks test, Wilcoxon rank-sum test, t-test, and χ2 test. RESULTS: The mean follow-up of the entire cohort was 73 ± 5.6 months. The lumbar Cobb angle in the STF group improved from 31.8 ± 6.5° to 11.5 ± 5.1° after the operation and 10.3 ± 6.9° at the last follow-up. The postoperative correction rate of the lumbar curve was 63.8%, which increased to 67.7% at the last follow-up. In the NSTF group, the lumbar Cobb angle improved from 34.3 ± 11.3° to 4.3 ± 3.7° after the operation, and was 5.1 ± 3.1° at the last follow-up. The postoperative correction rate of the lumbar curve was 87.4%, and 85.1% at the last follow-up. At the last follow-up, the STF group had higher overall HRQOL scores than the NSTF group, and there were statistically differences between the different groups (STF/NSTF) in SRS-30-Mental health (p = 0.03), SRS-30-Satisfaction with management (p = 0.02), SRS-30-Pain (p = 0.03), ODI (p = 0.01), SF-12 PCS (p = 0.03), VAS back pain (p = 0.005) and VAS leg pain (p = 0.001). No statistically differences were found in SF12 MCS, SRS-30-Self-image/Appearance and SRS-30 Function/activity. CONCLUSION: After 4-10 years of follow-up, we found that the STF group achieved satisfactory correction results, and compared with the NSTF group, their overall HRQOL scores were higher, especially in terms of pain and satisfaction, where the STF group shows a significant advantage.

The Association between High Preoperative MRI-based Vertebral Bone Quality (VBQ) Score and Titanium Mesh Cage Subsidence after Anterior Cervical Corpectomy and Fusion.

OBJECTIVE: Recently, the MRI-based vertebral bone quality (VBQ) score has been shown to correlate with Hounsfeld units (HU) value, dual-energy X-ray absorptiometry (DEXA) T-score and predict osteoporotic fractures. Preoperative cervical HU value is an independent correlative factor for early titanium mesh cage (TMC) subsidence after anterior cervical corpectomy and fusion (ACCF). However, to date the direct association between cervical VBQ score and TMC subsidence has not been studied. This study aims to investigate the predictive effect of cervical VBQ score derived from sagittal non-contrast-enhanced T1-weighted MRI on the early TMC subsidence after ACCF. METHODS: Patients who underwent one-level ACCF from January 2016 to January 2020 were included. We retrospectively collected baseline data on age, sex, body mass index (BMI), disease type, level of surgery and radiology parameters. The cervical VBQ score was measured using preoperative non-contrast-enhanced T1-weighted MRI. Univariate and multivariate logistic regression analysis were performed to screen the independent risk factors of TMC subsidence. The receiver operating characteristic (ROC) curve and area under curve (AUC) were performed to assess the predictive ability of TMC subsidence based on the cervical VBQ score. Spearman correlation analysis was used to determine the correlations between the cervical VBQ score and TMC subsidence. RESULTS: A total of 134 patients who underwent one-level ACCF were included in this study, and 46 (34.33%) patients had TMC subsidence. Univariable analyses demonstrated that the age, TMC placement depth and VBQ score were associated with subsidence. The cervical VBQ score in the subsidence group was significantly higher than that in the no subsidence group (3.75 ± 0.45 vs. 3.20 ± 0.42, p < 0.001). The multivariate logistic regression analysis proved that the higher VBQ score (odds ratio[OR] = 13.563, 95% confidence interval [CI] 4.968 - 37.031, p < 0.001) was the only variable that significantly predicted subsidence. Using a VBQ score cutoff value of 3.445, the cervical VBQ score yielded a sensitivity of 69.6% and a specificity of 85.2% with an AUC of 0.810 to differentiate patients with subsidence and with no subsidence. CONCLUSION: Preoperative higher cervical VBQ score is an independent risk factor for TMC subsidence after ACCF. The cervical VBQ score may be a valuable tool for assisting in distinguishing the presence of TMC subsidence.

Simplified S1 vertebral bone quality (vbq) score to assess proximal junctional kyphosis after Lenke 5 adolescent idiopathic scoliosis surgery.

BACKGROUND: Proximal junctional kyphosis (PJK) is a common complication following corrective surgery for adolescent idiopathic scoliosis (AIS) with a Lenke 5 curve. Previous studies have suggested that PJK may be associated with osteopenia, which is prevalent in AIS patients. MRI-based vertebral bone quality (VBQ) scores have been proposed as a valuable tool to assess preoperative bone quality. However, accurately measuring VBQ scores in Lenke 5 AIS patients with a structural lumbar curve can be challenging. Recently, a simplified S1 VBQ score has been proposed as an alternative method when the traditional VBQ score is not applicable. This study aims to evaluate the predictive value of the simplified S1 VBQ score in predicting the occurrence of PJK after corrective surgery for Lenke 5 AIS. METHODS: We conducted a retrospective analysis of patient data to assess the predictive utility of the S1 VBQ score for PJK in Lenke 5 AIS patients. Demographic, radiographic, and surgical data were collected, and S1 VBQ scores were calculated based on preoperative T1-weighted MRI images. Univariate analysis, linear regression, and multivariate logistic regression were performed to identify potential risk factors for PJK and to assess the correlation between other variables and the S1 VBQ score. Receiver operating characteristic analysis and area under the curve values were used to evaluate the predictive efficiency of the S1 VBQ score for PJK. RESULTS: A total of 105 patients (aged 15.50 ± 2.36 years) were included in the analysis, of whom 24 (22.9%) developed PJK. S1 VBQ scores were significantly higher in the PJK group compared to the non-PJK group (2.83 ± 0.44 vs. 2.48 ± 0.30, P < 0.001), and there was a significant positive correlation between the S1 VBQ score and proximal junctional angle (PJA) (r = 0.46, P < 0.0001). Multivariate analysis revealed that the S1 VBQ scores and preoperative thoracic kyphosis (TK) were significant predictors of PJK. CONCLUSION: This study provided evidence that higher S1 VBQ scores were independently associated with PJK occurrence following corrective surgery for Lenke 5 AIS. Preoperative measurement of the S1 VBQ score on MRI may serve as a valuable tool in planning surgical correction for Lenke 5 AIS.

A Novel Multiple Screw Distraction Reducer System in the Treatment of Scoliosis with a Severe Rib Hump.

OBJECTIVES: The treatment of scoliosis with a severe rib hump remains a major challenge. Traditional vertebral rotation techniques are not satisfactory, and thoracoplasty has many pulmonary complications that limit its application. A novel surgical device, the multiple screw distraction reducer (MSDR) system, provides longitudinal distraction during the corrective operation while at the same time providing lateral translation and axial derotation, which may facilitate the correction of a rib hump. This study was performed to investigate the effectiveness of the MSDR system for adolescent idiopathic scoliosis (AIS) with a severe rib hump. METHODS: This was a case-matched study of patients with retrospectively collected data from our hospital between January 2017 and December 2021. Sixty-eight patients who underwent one-stage posterior pedicle screw-instrumented spinal fusion were matched by the Cobb angle of the main curve and rib hump. All patients underwent a minimum of 2 years of follow-up. The patients were divided into two groups: the MSDR group (using the MSDR system, n = 34) and the DVR group (using direct vertebral derotation, n = 34). The patients were evaluated for the height of the rib hump, deformity correction, complications, and SRS-30 scores. The unpaired Student's t-test and Pearson's χ2 -test were used to compare the outcome measures between the two groups. Multiple linear regression analysis was used to examine the variables that affected the correction of a rib hump. RESULTS: The rib hump was 30.21 ± 6.21 mm versus 29.35 ± 6.52 mm (p = 0.583) preoperatively and 9.18 ± 4.06 mm versus 13.82 ± 5.54 mm (p < 0.001) at the last follow-up in the MSDR and DVR groups, respectively. The correction rates were 70.83% and 53.56%, respectively (p < 0.001). Preoperatively, the main thoracic curve was 58.43° ± 7.97° and 57.84° ± 6.32° (p = 0.736) and was corrected to 10.92° ± 5.47° and 19.14° ± 5.32° (p < 0.001) at last follow-up in the MSDR and DVR group, respectively. Thoracic kyphosis was restored from 18.24° ± 5.19° and 17.98° ± 5.28° (p = 0.836) in the MSDR and DVR group to 24.59° ± 4.41° and 19.32° ± 4.96° (p < 0.001), respectively. Correction of apical vertebra rotation and translation in the main thoracic curve were significantly better in the MSDR group than in the DVR group (p < 0.05). There was no significant difference in the Lenke type, implant density, estimated blood loss, or follow-up duration between the two groups, whereas the operation time in the DVR group was significantly less than that in the MSDR group. There were only two minor pulmonary complications in the MSDR group. At the last follow-up, the MSDR group scored higher in terms of appearance and satisfaction (p < 0.05). CONCLUSION: The MSDR system, enabling better coronal alignment, thoracic kyphosis, and axial derotation, could be a safe and effective technique for severe rib hump correction in AIS.

Comparison of Long-term Follow-Up of n-HA PA66 Cage and PEEK Cage of Lumbar Interbody Fusion in Multi-level Degenerative Lumbar Diseases: A Stepwise Propensity Score Matching Analysis.

OBJECTIVE: Previous studies have confirmed that the nanohydroxyapatite/polyamide-66 (n-HA/PA66) cage is an ideal alternative material for degenerative lumbar disease (DLD) comparable to the polyether ether ketone (PEEK) cage due to its similar radiographic fusion, subsidence rate, and clinical results. However, these studies were restricted to one-level surgery. The aim of this study was to analyze the long-term clinical and radiologic outcomes between n-HA PA66 cage and PEEK cage for patients with multi-level degenerative lumbar diseases (DLDs). METHODS: We retrospectively reviewed all patients who underwent multi-level transforaminal lumbar interbody fusion (TLIF) from June 2010 to December 2016 with a minimum 6-year follow-up. Matched-pair analysis was performed using a 1-to-1 closest neighbor approach to match patients who received an n-HA PA66 cage with those who received a PEEK cage. Clinical outcomes and radiographic evaluations were compared between the two groups. The independent student's t-test and χ2 -test were applied to compare the differences between groups. RESULTS: At the end of the propensity score matching (PSM) analysis, 48 patients from n-HA/PA66 group were matched to 48 patients in the PEEK group. No significant difference was observed in cage subsidence and bony fusion except for adjacent segment degeneration (ASD). The occurrence of ASD was 14.58% (7/48) in the n-HA/PA 66 group, which was significantly less than that in the PEEK group (33.33% [16/48]) (p = 0.031). Although the intervertebral space height (IH), segmental angle (SA) and lumbar lordosis (LL) significantly increased after surgery in both groups, there was no significant difference at any time point after surgery (p > 0.05). The visual analogue scale (VAS) and Oswestry disability index (ODI) scores significantly improved in both groups at 3m postoperative, 1y postoperative and at final follow-up. However, there were no significant differences in the VAS and ODI score at any time point (p > 0.05). The total complications and re-admission rate were not different between the two groups. CONCLUSION: Overall, our data suggest that the outcomes of n-HA/PA66 cage group are comparable to those of the PEEK cage group, with a similar high fusion rate and low cage subsidence rate as PEEK cages, except its lower rate of ASD occurrence.

Restoring the ideal Roussouly sagittal alignment in Lenke 5 adolescent idiopathic scoliosis patients: a method for decreasing the risk of proximal junctional kyphosis.

PURPOSE: Although the Roussouly classification has been widely used in surgical planning for adult scoliosis patients, little is known about whether it can be used to guide sagittal correction for adolescent idiopathic scoliosis (AIS) patients. The purpose of this study was to explore whether the Roussouly classification could be used to help surgeons restore the ideal sagittal alignment for AIS patients to avoid the development of proximal junctional kyphosis (PJK). METHODS: In this retrospective cohort study, eighty-seven patients with Lenke 5 AIS who underwent surgery from January 2010 to August 2020 were enrolled and divided into two groups: the PJK group and the non-PJK group. All patients were classified into "current types" and "ideal types" according to two versions of the Roussouly classification, and the mismatch rate was evaluated in terms of the consistency between their current type and ideal type. Student's t test, Mann‒Whitney U test, Pearson's Chi-square test, and others were used to compare the two groups regarding patient demographic characteristics (age, sex, Risser sign, etc.) and radiographic parameters (sagittal vertical axis [SVA]; thoracic kyphosis [TK]; thoracolumbar junctional kyphosis [TLK]; lumbar lordosis [LL]; pelvic incidence [PI]; pelvic tilt [PT]; sacral slope [SS]; upper instrumented vertebra [UIV]; lower instrumented vertebra [LIV]; etc.). Multivariate logistic regression with backwards stepwise selection was performed to identify the risk factors for PJK. RESULTS: PJK was observed in 16 out of 87 patients (18.4%) until the final follow-up. The incidence of PJK was significantly higher in the patients not matching their ideal type than in those who did after surgery (60.9% vs. 3.1%, p = 0.000). The patients with ideal Type 1 had the highest incidence of PJK, while the lowest incidence was observed in patients with ideal Type 2 (50.0% vs. 5.1%, p = 0.000). The PJK group had greater TK, LL, and PI-LL than the non-PJK group before and after surgery. The postoperative PJA in the PJK group was also larger than that in the non-PJK group. Multivariate logistic regression revealed that postoperative Roussouly type mismatch was significantly associated with the occurrence of PJK (OR = 64.2, CI = 9.6-407.1, p = 0.000). CONCLUSIONS: The Roussouly classification could serve as a prognostic tool for PJK in Lenke 5 AIS patients. Corrective surgery should restore sagittal alignment with respect to the patient's ideal sagittal profile (according to the Roussouly classification based on the PI) to decrease the incidence of PJK in AIS patients.

Epidemiological and clinical features, treatment status, and economic burden of traumatic spinal cord injury in China: a hospital-based retrospective study.

Traumatic spinal cord injury is potentially catastrophic and can lead to permanent disability or even death. China has the largest population of patients with traumatic spinal cord injury. Previous studies of traumatic spinal cord injury in China have mostly been regional in scope; national-level studies have been rare. To the best of our knowledge, no national-level study of treatment status and economic burden has been performed. This retrospective study aimed to examine the epidemiological and clinical features, treatment status, and economic burden of traumatic spinal cord injury in China at the national level. We included 13,465 traumatic spinal cord injury patients who were injured between January 2013 and December 2018 and treated in 30 hospitals in 11 provinces/municipalities representing all geographical divisions of China. Patient epidemiological and clinical features, treatment status, and total and daily costs were recorded. Trends in the percentage of traumatic spinal cord injuries among all hospitalized patients and among patients hospitalized in the orthopedic department and cost of care were assessed by annual percentage change using the Joinpoint Regression Program. The percentage of traumatic spinal cord injuries among all hospitalized patients and among patients hospitalized in the orthopedic department did not significantly change overall (annual percentage change, -0.5% and 2.1%, respectively). A total of 10,053 (74.7%) patients underwent surgery. Only 2.8% of patients who underwent surgery did so within 24 hours of injury. A total of 2005 (14.9%) patients were treated with high-dose (≥ 500 mg) methylprednisolone sodium succinate/methylprednisolone (MPSS/MP); 615 (4.6%) received it within 8 hours. The total cost for acute traumatic spinal cord injury decreased over the study period (-4.7%), while daily cost did not significantly change (1.0% increase). Our findings indicate that public health initiatives should aim at improving hospitals' ability to complete early surgery within 24 hours, which is associated with improved sensorimotor recovery, increasing the awareness rate of clinical guidelines related to high-dose MPSS/MP to reduce the use of the treatment with insufficient evidence.

Different cervical vertebral bone quality scores for bone mineral density assessment for the patients with cervical degenerative disease undergoing ACCF/ACDF: computed tomography and magnetic resonance imaging-based study.

BACKGROUND: Bone mineral density (BMD) is important for the outcome of cervical spine surgery. As the gold standard of assessing BMD, dual-energy X-ray absorptiometry scans are often not ordered or go unreviewed in patients' charts. As the supplement, MRI-based vertebral bone quality (VBQ) was found to accurately predict osteopenia/osteoporosis and postoperative complications in lumbar spine. However, discussion of the efficiency of VBQ in cervical spine is lacking. And measurement methods of VBQ in cervical spine are diverse and not universally acknowledged like lumbar spine. We aimed to compare the predictive performance of three kinds of different Cervical-VBQ (C-VBQ) scores for bone mineral density assessment in patients undergoing cervical spine surgery. HU value of cervical spine was set as a reference. METHODS: Adult patients receiving cervical spine surgery for degenerative diseases were retrospectively included between Jan 2015 and Dec 2022 in our hospital. The VBQ scores and HU value were measured from preoperative MRI and CT. The correlation between HU value/C-VBQs (named C-VBQ1/2/3 according to different calculating methods) and DEXA T-score was analyzed using univariate linear correlation and Pearson's correlation. We evaluated the predictive performance of those two parameters and achieved the most appropriate cutoff value by comparing the receiver operating characteristic (ROC) curves. RESULTS: 106 patients (34 patients with T ≥ - 1.0 vs 72 patients with T < - 1.0) were included (mean age: 51.95 ± 10.94, 48 men). According to Pearson correlation analysis, C-VBQ1/2/3 and HU value were all significantly correlated to DEXA T-score (Correlation Coefficient (r): C-VBQ1: - 0.393, C-VBQ2: - 0.368, C-VBQ3: - 0.395, HU value: 0.417, p < 0.001). The area under the ROC curve (AUC) was calculated (C-VBQ1: 0.717, C-VBQ2: 0.717, C-VBQ3: 0.727, HU value: 0.746). The AUC of the combination of C-VBQ3 and HU value was 0.786. At last, the most appropriate cutoff value was determined (C-VBQ1: 3.175, C-VBQ2: 3.005, C-VBQ3: 2.99, HU value: 299.85 HU). CONCLUSIONS: Different MRI-based C-VBQ scores could all be potential and alternative tools for opportunistically screening patients with osteopenia and osteoporosis before cervical spine surgery. Among them, C-VBQ calculated in ASIC2-C7/SIT1-CSF performed better. We advised patients with C-VBQ higher than cutoff value to accept further BMD examination.

Comparative evaluation of multi-fold rib and structural iliac bone grafts in single-segment thoracic and thoracolumbar spinal tuberculosis: clinical and radiological outcomes.

OBJECTIVE: To compare clinical and radiological outcomes of multi-fold rib and structural iliac bone grafts, the primary autologous graft techniques in anterolateral-only surgery for single-segment thoracic and thoracolumbar spinal tuberculosis. METHODS: This retrospective study included 99 patients treated from January 2014 to March 2022, categorized into 64 with multi-fold rib grafts (group A) and 35 with structural iliac bone grafts (group B). Outcomes assessed included hospital stay, operation time, intraoperative blood loss, postoperative drainage, complications, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), the Visual Analog Scale (VAS) for pain, the Oswestry Disability Index (ODI), bone fusion time, and the American Spinal Injury Association (ASIA) impairment scale grade. Segmental kyphotic angle and intervertebral height were measured radiologically before surgery and follow-up. RESULTS: The mean follow-up was 63.50 ± 26.05 months for group A and 64.97 ± 26.43 months for group B (P > 0.05). All patients had achieved a clinical cure. Group A had a shorter operation time (P = 0.004). Within one week post-surgery, group B reported higher VAS scores (P < 0.0001). Neurological performance and quality of life significantly improved in both groups. No significant differences were observed in segmental kyphotic angle and intervertebral height between the groups pre- and postoperatively (P > 0.05). However, group A showed a greater segmental kyphotic angle at the final follow-up, while group B had better maintenance of kyphotic angle correction and intervertebral height (P < 0.05). Bone fusion was achieved in all patients without differences in fusion time (P > 0.05). CONCLUSIONS: Multi-fold rib grafts resulted in shorter operation times and less postoperative pain, while structural iliac bone grafts provided better long-term maintenance of spinal alignment and stability, suggesting their use in cases where long-term outcomes are critical.

Postoperative Sclerotic Modic Changes after Transforaminal Lumbar Interbody Fusion: The Prevalence, Risk Factors, and Impact on Fusion.

STUDY DESIGN: A retrospective cohort study. OBJECTIVE: This study aimed to assess postoperative sclerotic Modic changes (MCs) following transforaminal lumbar interbody fusion (TLIF) for lumbar degenerative disc disease (LDD), investigating their prevalence, risk factors and association with clinical outcomes. SUMMARY OF BACKGROUND DATA: Sclerotic MCs may occur in patients with LDD after lumbar interbody fusion. The incidence and characteristics of postoperative sclerotic MCs, as well as their clinical impact, are unknown. METHODS: The study included 467 patients (510 levels) who underwent single or two-level TLIF surgery, divided into a postoperative sclerotic MC group (60 patients, 66 levels) and non-MC group (407 patients, 444 levels). The time of development and location of postoperative sclerotic MCs, fusion rate, cage subsidence, bilateral process decompression, and cross-link usage were recorded. Preoperative, postoperative, and follow-up VAS and ODI scores were collected. Multivaraible logistic regression was used to evaluate factors associated with the development of postoperative sclerotic MCs. RESULTS: The prevalence of postoperative sclerotic MCs was 12.8%. The postoperative sclerotic MC group had higher BMI. The postoperative sclerotic MC group demonstrated a fusion rate of 47%, significantly lower than that of the non-MC group (71%) at 6 months post-operation. At final follow-up, the fusion rate in the postoperative sclerotic MC group was 62%, significantly lower than that of the non-MC group (86%). Post-operative VAS and ODI scores were significantly higher in the group with postoperative sclerotic MCs. BMI and osteoporosis were significantly associated with the development of postoperative sclerotic MCs. CONCLUSION: Postoperative sclerotic MCs generally appear within the first year after surgery, with a prevalence of 12.8%. The presence of postoperative sclerotic MCs can adversely impact post-operative outcomes. To prevent postoperative sclerotic MCs, we postulate extending the immobilization period with external bracing and improving the management of BMI and osteoporosis in the peri-operative time window.

A Comparison of Corpectomy ACDF Hybrid Procedures with Nano-Hydroxyapatite/Polyamide 66 Cage and Titanium Mesh Cage for Multi-level Degenerative Cervical Myelopathy: A Stepwise Propensity Score Matching Analysis.

OBJECTIVE: Previous studies have found satisfactory clinical results with the nano-hydroxyapatite/polyamide 66 (n-HA/PA66) cage to reconstruct the stability of anterior cervical column. However, studies evaluating the long-term outcomes of the n-HA/PA66 cage in multi-level degenerative cervical myelopathy (MDCM) have not been reported. This study aims to compare the outcomes of corpectomy anterior cervical discectomy and fusion (ACDF) hybrid procedures between the n-HA/PA66 cage and titanium mesh cage (TMC) to treat MDCM. METHODS: After the screening for eligibility, this retrospective study involved 90 patients who underwent corpectomy ACDF hybrid (CACDFH) procedure from June 2013 to June 2018. The CACDFH procedure is the combination of ACDF and anterior cervical corpectomy and fusion (ACCF). According to the cage utilized, we categorized patients into a n-HA/PA66 cage group and a TMC group. Then, stepwise propensity score matching (PSM) was performed to maintain comparable clinical data between groups. All the patients were followed up ≥4 years and the longest follow-up time was 65.43 (±11.49) months. Cage subsidence, adjacent segment degeneration (ASD), segmental height (SH), segmental angle (SA), cervical lordosis (CL), and clinical data (visual analogue scale [VAS] and Japanese Orthopaedic Association [JOA] score) was evaluated preoperatively, at 1 week, and at the final surgery follow-up. The independent student's t test and chi-square test were applied to compare the differences between groups. RESULTS: Through PSM analysis, 25 patients from the n-HA/PA66 group were matched to 25 patients in the TMC group. The occurrence of ASD was 16.0% (4/25) in the n-HA/PA 66 group, which was significantly less than in the TMC group at 44.0% (11/25) (p = 0.031). Moreover, the cage subsidence rate was significantly higher in the TMC group as compared to the n-HA/PA 66 group (40.0% vs. 12.0%, p = 0.024). But there was no significant difference in SH, SA, and CL at any time after surgery as determined through follow-up. The VAS and JOA scores significantly improved in both groups at 3 months postoperative and at final follow-up. However, there were no significant differences in the VAS and JOA score at any time between the two groups in preoperative (p > 0.05). CONCLUSION: The n-HA/PA66 cage is associated with lower rate of cage subsidence and ASD than the TMC in the treatment of MDCM. The n-HA/PA66 cage could be superior to the TMC in corpectomy ACDF hybrid procedures.