Surgical treatment of spinal tuberculosis: an updated review

Tuberculosis (TB) is a worldwide disease which seriously affects the global public health. Spinal TB is the most common extra-pulmonary TB and may cause vertebral bone destruction, collapse, kyphosis and even paralysis. Anti-TB chemotherapy is considered the cornerstone treatment of spinal TB and surgery is often required for patients with severe kyphosis, impaired neurological function or spinal instability. Debridement of TB lesions, bone grafting and internal fixation are the key procedures of spinal TB surgery. However, the selection of surgical approach, the extent of TB lesion debridement, the choice of bone graft materials, and the method and extent of internal fixation are all remain controversy. The aim of this updated review is to evaluate current literature for advances in management of spinal TB, with particular focus on surgical techniques.

A Comparative Study of Anterior and Posterior Tuberculosis Lesions for the Treatment of Thoracolumbar Tuberculosis disease: A Single Institution Experience in a Major Academic Hospital

Objective

To compare the efficacy of anterior and posterior surgery for thoracolumbar tuberculosis disease.

Methods

Clinical data of 30 patients with thoracolumbar tuberculosis disease undergoing anterior and posterior surgery from January 2021 to December 2023 were collected for a retrospective study. According to the two surgical procedures, patients were divided into two groups: 1) anterior group (n=15) and 2) posterior group (n=15). We compared the two groups regarding age, gender, body mass index, affected segments, past history (cardiovascular and cerebrovascular diseases, respiratory diseases, endocrine system diseases, metabolic diseases, and tuberculosis history), smoking history, drinking history, operation time, postoperative bleeding, postoperative drainage, postoperative time, postoperative complications (dural tear, lower limb intermuscular vein thrombosis, lower limb deep vein thrombosis, sinus infection, postoperative recurrence rate), and waist VAS score before and after surgery, waist ODI score, and JOA score.

Results

The intraoperative blood loss was significantly less in the posterior group than in the anterior group, and the difference was significant (P <0.05); the lumbar VAS score was lower in the posterior group than in the anterior group, and the difference between the two groups was significant (P <0.05). The analysis of the remaining data showed no significant difference between the two groups (P> 0.05), indicating that the efficacy of the two procedures was the same.

Conclusion

In the treatment of thoracolumbar tuberculosis disease, there is no significant difference in the clinical efficacy of anterior surgery and posterior surgery. Intraoperative bleeding in posterior surgery was less than in anterior surgery, but the latter showed a significant improvement in postoperative pain relief. Therefore, spinal surgeons should choose the corresponding surgical treatment according to the actual situation of the patient in order to maximize the efficacy.

A Comparison of Clinical Outcomes Between Anterior Cervical Discectomy and Fusion Versus Posterior Cervical Laminoplasty for Multilevel Cervical Myelopathy

STUDY DESIGN

Retrospective Cohort.

OBJECTIVE

To compare patient-reported outcomes and surgical outcomes after anterior cervical discectomy and fusion (ACDF) versus cervical laminoplasty for multilevel cervical spondylotic myelopathy.

BACKGROUND

Treatment options for multilevel cervical spondylotic myelopathy include ACDF and cervical laminoplasty. Given that the literature has been mixed regarding the optimal approach, especially in patients without kyphosis, there is a need for additional studies investigating outcomes between ACDF and cervical laminoplasty.

METHODS

A retrospective review was conducted of adult patients undergoing 3 or 4-level surgery. Patients with preoperative kyphosis based on C2-C7 Cobb angles were excluded. The electronic medical record and institutional databases were reviewed for baseline characteristics, surgical outcomes, and patient-reported outcomes.

RESULTS

A total of 101 patients who underwent ACDF and 52 patients who underwent laminoplasty were included in the study. The laminoplasty cohort had a higher overall Charlson Comorbidity Index (3.10 ± 1.43 vs 2.39 ± 1.57, P = 0.011). Both groups had a comparable number of levels decompressed, C2-C7 lordosis, and diagnosis of myelopathy versus myeloradiculopathy. Patients who underwent laminoplasty had a longer length of stay (2.04 ± 1.15 vs 1.48 ± 0.70, P = 0.003) but readmission, complication, and revision rates were similar. Both groups had similar improvement in myelopathy scores (∆modified Japanese Orthopedic Association: 1.11 ± 3.09 vs 1.06 ± 3.37, P = 0.639). ACDF had greater improvement in Neck Disability Index (∆Neck Disability Index: -11.66 ± 19.2 vs -1.13 ± 11.2, P < 0.001), neck pain (∆Visual Analog Scale-neck: -2.69 ± 2.78 vs -0.83 ± 2.55, P = 0.003), and arm pain (∆Visual Analog Scale-arm: -2.47 ± 3.15 vs -0.48 ± 3.19, P = 0.010). These findings persisted in multivariate analysis except for Neck Disability Index.

CONCLUSION

ACDF and cervical laminoplasty appear equally efficacious at halting myelopathic progression. However, patients who underwent ACDF had greater improvements in arm pain at 1 year postoperatively. Longitudinal studies evaluating the efficacy of laminoplasty to mitigate adjacent segment disease are indicated to establish a robust risk-benefit assessment for these 2 procedures.

LEVEL OF EVIDENCE

III.

Resveratrol inhibits Lin28A expression and induces its degradation via the proteasomal pathway in NCCIT cells

Lin28A is an oncoprotein overexpressed in several cancer types such as testicular, ovarian, colon, breast and lung cancers. As a pluripotency factor that promotes tumorigenesis, Lin28A is associated with more undifferentiated and aggressive tumors phenotypes. Moreover, Lin28A is a highly stable protein that is difficult to downregulate. The compound resveratrol (RSV) has anticancer effects. The present study aimed to elucidate the mechanisms underlying the downregulation of Lin28A protein expression by RSV in the NCCIT cell line. NCCIT cells were treated with different concentrations of RSV to investigate its effects on Lin28A expression. The mRNA expression levels of Lin28A and ubiquitin-specific protease 28 (USP28) were assessed using reverse transcription-quantitative PCR. Western blot analysis was employed to evaluate the protein levels of Lin28A, USP28 and phosphorylated Lin28A. In addition, in some experiments, cells were treated with a MAPK/ERK pathway inhibitor, and other experiments involved transfecting cells with small interfering RNAs targeting USP28. The results demonstrated that RSV significantly reduced Lin28A expression by destabilizing the protein; this effect was mediated by the ability of RSV to suppress the expression of USP28, a deubiquitinase that normally protects Lin28A from ubiquitination and degradation. Additionally, RSV inhibited phosphorylation of Lin28A via the MAPK/ERK pathway; this phosphorylation event has previously been shown to enhance the stability of Lin28A by increasing its half-life. This resulted in Lin28A degradation through the proteasomal pathway in NCCIT cells. The results provide further evidence of the anticancer activity of RSV, and identified Lin28A and USP28 as promising therapeutic targets. As a stable oncoprotein, downregulating Lin28A expression is challenging. However, the present study demonstrated that RSV can overcome this hurdle by inhibiting USP28 expression and MAPK/ERK signaling to promote Lin28A degradation. Furthermore, elucidating these mechanisms provides avenues for developing targeted cancer therapies.

Postoperative adding-on phenomenon in Lenke 1A/B and 2A/B adolescent idiopathic scoliosis: risk factors and predictive index

PURPOSE

The aim of this study was to identify associated risk factors of distal adding-on phenomenon in Lenke 1A/B and 2A/B adolescent idiopathic scoliosis (AIS) patients and establish the corresponding prediction model.

METHODS

The clinical data of 119 Lenke 1A/B and 2A/B AIS patients were retrospectively analyzed. Preoperative, first erect (FE) radiographic parameters and radiographic parameters at the last follow-up were measured. Patients were divided into the adding-on group and the no adding-on group according to whether the adding-on phenomenon was observed at the last follow-up. Univariate analysis and multivariate logistic regression analysis were used to establish the corresponding prediction model.

RESULTS

Adding-on affected 39 (32.8%) patients at the last follow-up. Risser sign and 19 radiographic parameters showed significant differences between the two groups by univariate analysis. Stepwise logistic regression analysis found that the Risser sign and so on five predictor variable, and the nomogram was drawn. The calibration curve showed that the model fitted well. The area under the receiver operating characteristic (ROC) curve is 0.949. And the decision curve analysis curve model within the threshold range for interventions to improve clinical outcomes. There was no significant difference in SRS-22 scores between the two groups.

CONCLUSIONS

This study established a prediction model with adding-on in Lenke 1A/B and 2A/B AIS patients. The nomogram contains five predictive variables, which can effectively predict the probability of adding-on phenomenon during follow-up, and may have greater clinical value for the treatment and prevention of adding-on phenomenon.

Emerging roles of long non-coding RNA FOXP4-AS1 in human cancers: From molecular biology to clinical application

Forkhead box P4 antisense RNA 1 (FOXP4-AS1) is a long non-coding RNA (lncRNA) situated on the human chromosome 6p21.1 locus. Previous research has demonstrated that FOXP4-AS1 is dysregulated in various cancers and exhibits a dual purpose as a tumor suppressor or oncogene in specific types of cancer. The levels of FOXP4-AS1 are significantly correlated with clinical features of cancer as well as prognosis. Additionally, FOXP4-AS1 is stimulated by transcription factors ATF3, YY1, PAX5, and SP4. The molecular mechanisms of FOXP4-AS1 in cancer are quite complex. It competitively sponges multiple miRNAs, bidirectionally regulates the levels of host gene FOXP4, activates the PI3K/AKT, Wnt/β-catenin, and ERK/MAPK signaling pathways, and recruits chromatin-modifying enzymes or interacts with other proteins to regulate malignant phenotypes of tumors, including proliferation, invasion, epithelial-mesenchymal transition (EMT), and angiogenesis. In this review, we provide an overview of the latest developments in FOXP4-AS1 oncology research, outlines its molecular regulatory networks in cancer, and discusses its prospective relevance as a cancer therapeutic target as well as a biomarker for prognosis and diagnosis.

Cervical Sagittal Alignment and Balance Associated With Aging Chinese Adults: A Radiographic Analysis

STUDY DESIGN

This was a retrospective cohort radiographic study.

OBJECTIVE

To determine the age- and gender-related normative values and correlation of cervical sagittal parameters in asymptomatic Chinese adults, and to explore the changes and compensating mechanisms across different age groups.

METHODS

The asymptomatic subjects were divided into 6 groups according to age and then one-way analysis of variance was used to compare the multiple sets of cervical sagittal parameters among the different age groups. Independent t-tests were performed to compare the sagittal parameters among different gender and different cervical spine alignments. Relationships between each parameter were tested by Pearson's correlation. Linear regression analysis based on T1 slope (T1S) and C2 slope (C2S) was used to provide an equation to predict normal cervical alignment.

RESULTS

Mean values of each cervical sagittal parameter were presented based on age and gender. There were positive correlations between age and cervical lordosis (CL) (r = -.278, P < .001), T1S (r = .271, P < .001), cervical sagittal vertical axis (cSVA) (r = .218, P < .001), C2-C4 Cobb angle (r = -.283, P < .001), horacic inlet angle (TIA) (r = .443, P < .001), and neck tilt (NT) (r = .354, P < .001). Older groups (aged >50 years) had greater T1 Slope, C2S, and TIA. The C2-C4 Cobb angle maintained a steadily increasing trend and significantly increased in the older adult groups (P < .05), while the C5-C7 Cobb angle was relatively constant. Mean values of parameters were larger in males (P > .05). Linear regression analysis indicated a strong association between T1S and CL (R2 = .551, standard error 1.16°), T1S and C5-7 (R2 = .372; P < .001), and C2S and C2-4 (R2 = .309; P < .001).

CONCLUSIONS

Normative values of cervical sagittal parameters vary by age and sex. The CL, cSVA, and T1S, C2-4 Cobb angle changed with increasing age, and it can influence the recruitment of compensation mechanism. Normative CL of Chinese adults was predicted by the equation CL = T1S-14.7° ± 1.2°, which could serve as a reference when planning for cervical surgery.

Ferroptosis in the neurovascular unit after spinal cord injury

The mechanisms of secondary injury following spinal cord injury are complicated. The role of ferroptosis, which is a newly discovered form of regulated cell death in the neurovascular unit(NVU), is increasingly important. Ferroptosis inhibitors have been shown to improve neurovascular homeostasis and attenuate secondary spinal cord injury(SCI). This review focuses on the mechanisms of ferroptosis in NVU cells and NVU-targeted therapeutic strategies according to the stages of SCI, and analyzes possible future research directions.

The role of WWP1 and WWP2 in bone/cartilage development and diseases

Bone and cartilage diseases are often associated with trauma and senescence, manifested as pain and limited mobility. The repair of bone and cartilage lesion by mesenchymal stem cells is regulated by various transcription factors. WW domain-containing protein 1 (WWP1) and WW domain-containing protein 2 (WWP2) are named for WW domain which recognizes PPXY (phono Ser Pro and Pro Arg) motifs of substrate. WWP1and WWP2 are prominent components of the homologous to the E6-AP carboxyl terminus (HECT) subfamily, a group of the ubiquitin ligase. Recently, some studies have found that WWP1 and WWP2 play an important role in the pathogenesis of bone and cartilage diseases and regulate the level and the transactivation of various transcription factors through ubiquitination. Therefore, this review summarizes the distribution and effects of WWP1 and WWP2 in the development of bone and cartilage, discusses the potential mechanism and therapeutic drugs in bone and cartilage diseases such as osteoarthritis, fracture, and osteoporosis.

Usefulness of modified S-line for upper instrumented vertebra selection in adolescent idiopathic scoliosis Lenke type 1C curve

PURPOSE

Determine the effect of using the modified S-line vertebra (MSLV) as the upper instrumented vertebra (UIV) on postoperative trunk balance, L4 tilt, and clinical outcomes in selective thoracic fusion (STF) for adolescent idiopathic scoliosis (AIS) Lenke type 1C curve.

METHODS

Twenty-eight consecutive patients (all female; mean age: 15.4±2.0 years) with AIS Lenke type 1C curve were retrospectively enrolled. Primary outcome measures were coronal balance (absolute distance between C7 and the center of the sacral vertical line), L4 tilt, and Scoliosis Research Society (SRS)-22r scores at 2 years postoperatively. The group with the MSLV at the UIV was designated as the MSLV group (18 patients), and the group with the MSLV proximal (12 patients) or distal (4 patients) to the UIV was defined as the non-MSLV group.

RESULTS

We observed no significant differences between the groups regarding age, LIV and stable vertebra positioning, or preoperative X-ray parameters. Postoperative coronal balance was significantly better in the MSLV group (0.39±0.08 vs. 1.34±0.22 cm; P.

Transforaminal Endoscopic Lumbar Diskectomy versus Open Microdiskectomy for Symptomatic Lumbar Disk Herniation: A Comparative Cohort Study on Costs and Long-Term Outcomes

BACKGROUND

 Transforaminal endoscopic lumbar diskectomy (TELD) is considered an effective treatment for lumbar disk herniation (LDH). There is a paucity of studies comparing in detail the costs and long-term clinical outcomes of TELD and open microdiskectomy (MD), especially in developing countries. Thus, we sought to provide a multidimensional insight into this matter by comparing the direct costs and long-term outcomes of TELD with those of MD.

METHODS

 The electronic health records of 434 patients with LDH who underwent either TELD or MD were collected from February 2011 to October 2014. Within a 7-year follow-up period, 412 patients, comprising 203 patients treated with TELD and 209 patients treated with MD, were fully evaluated. Patient characteristics, operative time, intraoperative blood loss (IBL), postoperative hospital stay, time to return to work (RTW), perioperative complications, and direct costs were collected. Clinical outcomes were assessed using the Visual Analog Scale (VAS), Oswestry Disability Index (ODI), and modified MacNab criteria.

RESULTS

 The postoperative ODI and VAS scores improved significantly in both groups (p < 0.001). In accordance with the modified MacNab criteria, the rate of excellent and good outcomes was 88.67 and 88.03% in the TELD and MD groups, respectively. There were no significant differences between the groups in the clinical outcomes and perioperative complications. However, IBL, hospital stay, and RTW were significantly reduced in the TELD group (p < 0.05). Twenty-one cases in the TELD group and nine in the MD group underwent reoperation due to recurrence (p < 0.05). Total inpatient cost per patient was $1,596 in the TELD group and $1,990 in the MD group (p < 0.05).

CONCLUSION

 TELD for the treatment of symptomatic LDH could be an affordable strategy, providing certain advantages of minimally invasive procedures such as shorter hospital stay and earlier recovery along with comparable clinical outcomes to the conventional surgical method.

A Novel Classification of Migrated Lumbar Disk Herniation Based on Magnetic Resonance Imaging and Algorithm Recommendations for Full-Endoscopic Discectomy

STUDY DESIGN

Retrospective clinical study.

OBJECTIVE

The purpose of this study was to establish a novel classification of migrated lumbar disk herniation (LDH) based on magnetic resonance imaging and provide appropriate treatment strategies for each type through algorithms.

SUMMARY OF BACKGROUND DATA

Full-endoscopic lumbar discectomy is a surgical technique that has been developed rapidly in recent years. For migrated LDH, few surgeons currently classify it with multiplanar positioning, and there is no consensus on the choice of treatment strategy. Therefore, we established a new multiplanar classification criteria that can localize the lesions more accurately than previous studies.

METHODS

A total of 263 eligible patients from March 2017 to March 2022 were included. Protrusions for each patient were located based on our classification and the surgical approach was selected according to our algorithms. The clinical symptoms of all patients before surgery, and at 1 day, 1 month, 3 months, 6 months, and 12 months after surgery were collected. Evaluations were performed using visual analogue scale (VAS), Oswestry Disability Index (ODI) and modified MacNab criteria. We used the chi-squared test, one-way analysis of variance (ANOVA), and t-test to compare perioperative results and postoperative 3-month, 6-month, and 12-month follow-up results.

RESULTS

VAS (low back pain) scores were reduced from 5.33 ± 2.67 to 0.73 ± 0.77 (p < 0.001), and VAS (leg pain) scores were reduced from 7.44 ± 2.21 to 0.37 ± 0.51 (p < 0.001). ODI scores improved from 58.46 ± 8.04 to 12.57 ± 2.51 (p < 0.001). According to the modified MacNab criteria, the excellent and good rate reached 92.78% at the 12-month follow-up. Twenty-six patients developed complications, all of which improved after treatment. Recurrence occurred in 13 patients, and four of them underwent secondary surgery.

CONCLUSIONS

This is an innovative classification method using multi-plane positioning, and the algorithm used with it can help surgeons make appropriate choices when using endoscopic technology to treat migrated LDH. Statistical analysis of follow-up data confirmed that this is a safe and effective strategy.

Minimally invasive far lateral tubular microdiscectomy: surgical technique and case series of 176 patients

BACKGROUND

Far lateral (extraforaminal) disc herniations comprise approximately 10% of symptomatic lumbar disc herniations. They represent operative challenges due to accessibility and surgical unfamiliarity. Surgical strategies in the past have included open discectomy and posterior lumbar interbody fusion. Tubular microdiscectomies have gained traction due to their minimally invasive advantages, including reduced morbidity, pain and length of hospital stay.

METHODS

We report our retrospective single institution consecutive case series of tubular far lateral microdiscectomies. One hundred and seventy-six patients were operated on over an eight-year period. Clinical outcomes were assessed after institutional ethics approval. We additionally describe our surgical technique with an illustrative video case.

RESULTS

Over a mean follow-up of 21 weeks, 77% of patients had good or excellent clinical outcomes according to the MacNab criteria. 12% of patients underwent reoperation at the index level for symptom recurrence or persistence. Mean length of hospital stay was 1.3 days. There was a 1% rate of both postoperative haematoma and infection. Mean operation duration was 86 minutes.

CONCLUSION

This case series represents the largest currently reported in the literature. Minimally invasive microdiscectomies performed through tubes allow for precise localisation, reduced tissue disruption and favourable clinical outcomes. Our results appear consistent with a review of the literature, demonstrating the safety and efficacy of this approach.

Development and validation of a novel endoplasmic reticulum stress-related lncRNAs signature in osteosarcoma

Osteosarcoma (OS) is a cancerous tumor, and its development is greatly influenced by long non-coding RNA (lncRNA). Endoplasmic reticulum stress (ERS) is an essential biological defense process in cells and contributes to the progression of tumors. However, the exact mechanisms remain elusive. This study aims to develop a signature of lncRNAs associated with ERS in OS. This signature will guide the prognosis prediction and the determination of appropriate treatment strategies. The UCSC Xena database collected transcriptional and clinical data of OS and muscle, after identifying ERS differentially expressed genes, we utilized correlation analysis to determine the endoplasmic reticulum stress lncRNAs (ERLs). The Least Absolute Shrinkage and Selection Operator (LASSO) and Cox regression analysis were utilized to develop an ERLs signature. To clarify the fundamental mechanisms controlling gene expression in low and high-risk groups, Gene Set Variation Analysis (GSVA) were conducted. In addition, the distinction between the two groups regarding drug sensitivity and immune-related activity was investigated to determine the immunotherapy effects. Utilizing RT-qPCR, the expression of model lncRNAs in OS cell lines was ascertained. The functional analysis of LINC02298 was carried out through in vitro experiments and pan-cancer analysis. This study successfully constructed an ERLs prognostic signature for OS, which comprised 5 lncRNAs (AC023157.3, AL031673.1, LINC02298, LINC02328, SNHG26). The risk signature predicted overall survival in patients with OS and was confirmed by assessing the validation and whole cohorts. Further, it was discovered that individuals classified as high-risk displayed suppressed immune activation, decreased infiltration of immune cells, and decreased responsiveness to immunotherapy. The RT-qPCR showed that the constructed risk prognosis model is reliable. Experimental validation has demonstrated that LINC02298 can promote OS cells' invasion, migration, and proliferation. In addition, LINC02298 exhibited significant differential expression in many types of cancer. Moreover, LINC02298 is an important biomarker in a variety of tumors. This study established a novel ERLs signature, which successfully predicted the prognosis of OS. The function of LINC02298 in OS was elucidated via in vitro experiments. Therefore, it offers new opportunities for predicting the clinical prognosis of OS and establishes the basis for targeted therapy in OS.

Surgical options for metastatic spine tumors: WFNS spine committee recommendations

Surgical treatments for metastatic spine tumors have evolved tremendously over the last decade. Improvements in immunotherapies and other medical treatments have led to longer life expectancy in cancer patients. This, in turn, has led to an increase in the incidence of metastatic spine tumors. Spine metastases remain the most common type of spine tumor. In this study, we systematically reviewed all available literature on metastatic spine tumors and spinal instability within the last decade. We also performed further systematic reviews on cervical metastatic tumors, thoracolumbar metastatic tumors, and minimally invasive surgery in metastatic spine tumors. Lastly, the results from the systematic reviews were presented to an expert panel at the World Federation of Neurosurgical Societies (WFNS) meeting, and their consensus was also presented.

A rib-sparing unilateral transpedicular thoracic corpectomy using the ultrasonic bone scalpel: a novel technique and pictorial guide

BACKGROUND

The thoracic corpectomy is a well-described technique for the surgical treatment of vertebral column fractures with spinal canal compromise. Traditionally, the posterolateral approach to this procedure required the removal of the approach side rib in order to introduce the corpectomy cage. This rib removal, however, has been identified as a major contributor to post-operative morbidity. Rib-sparing techniques have been shown to be beneficial in minimizing post-operative morbidity in non-spinal surgeries. Herein, we present a previously undescribed technique of a rib-sparing thoracic corpectomy that avoids sequalae of rib resection with assistance from an ultrasonic bone scalpel (UBS).

METHODS

A retrospective chart review was conducted on patients having undergone this thoracic corpectomy technique. Data on patient age at operation, indication for surgery, number of corpectomies per case, estimated blood loss (EBL), operative time (OT), intra-operative complications, and post-operative length of stay (LOS) were collected and analyzed. A pictorial step-by-step guide was created to highlight the advantages of an entirely posterior rib-sparing unilateral transpedicular technique for thoracic corpectomy.

RESULTS

A total of 36 corpectomies were performed on 32 patients between August 2015 and March 2023. Patients ages ranged from 17 to 85 years (mean = 63). The most common indication was oncological (n = 22, 69%), followed by degenerative/traumatic deformity (n = 7, 22%), and infection (n = 3, 9%). For the cases for which data was accessible, mean EBL was 853 cc and mean OT was 178 min. The average post-operative LOS was 6.5 days.

CONCLUSION

The described surgical approach makes it possible to create a transpedicular corridor with no costectomy for implantation of an expandable titanium cage and anterior column reconstruction. The use of the UBS in this approach is critical as it minimizes bony removal and avoids sequelae of rib resection. The described technique has the potential to circumvent post-costectomy pain, thereby expediting post-operative recovery after thoracic corpectomy.

Excessive posterior placement of upper instrumented vertebra relative to lower instrumented vertebra as a predictor of proximal junction kyphosis after selective spinal fusion for adolescent idiopathic scoliosis Lenke type 5C curves

PURPOSE

We defined sagittal S-line tilt (SSLT) as the tilt of the line connecting the upper instrumented vertebra and the lower instrumented vertebra. This study aimed to: (1) examine the correlation between SSLT and proximal junctional angle (PJA) change values, and (2) determine the cut-off value of SSLT with respect to proximal junctional kyphosis (PJK) occurrence.

METHODS

Eighty-six consecutive patients (81 female and 5 male; mean age: 15.8 years) with Lenke 5C AIS who underwent posterior selective spinal fusion. Pearson's correlation coefficients were used to examine the relationship between preoperative SSLT and changes in PJA from preoperative to 2 years postoperative. The impact of SSLT on PJK at 2 years after surgery was assessed using a receiver operating characteristic (ROC) curve.

RESULTS

We observed a moderate positive correlation between preoperative SSLT and change in PJA (R = 0.541, P < 0.001). We identified 18 patients (21%) with PJK at 2 years postoperative. Mean preoperative SSLT in the PJK group and the non-PJK group differed significantly at 23.3 ± 4.1° and 16.1 ± 5.0°, respectively (P < 0.001). The cut-off value of preoperative SSLT for PJK at 2 years postoperative was 18° in ROC curve analysis, with a sensitivity of 94%, specificity of 68%, and area under the ROC curve of 0.868.

CONCLUSION

In selective lumbar fusion for AIS Lenke type 5C curves, preoperative SSLT was significantly correlated with PJA change from preoperative to 2 years postoperative. SSLT was a predictor of PJK occurrence, with a cut-off value of 18°.

Analyzing Factors Associated with Postoperative Shoulder Imbalance in Lenke2 Adolescent Idiopathic Scoliosis (Retrospective Cohort Study)

OBJECTIVE

To assess the incidence of postoperative shoulder imbalance (PSI) following posterior spinal fusion surgeries in adolescent idiopathic scoliosis (AIS) with Lenke2 and calculate the risk factors for PSI.

METHODS

Sixty patients who underwent surgery for Lenke2 AIS with more than 2-year follow-up were selected. Radiographic parameters were measured before and after surgery, and at the latest follow-up. The patients were divided into PSI and non-PSI groups, with PSI defined as a radiographic shoulder height >15 mm on postoperative radiography. The factors were compared between the PSI and non-PSI groups using the Mann-Whitney U test or chi-squared test. Finally, explanatory variables were chosen for multivariate analysis based on previous studies.

RESULTS

The PSI group comprised 17 patients. Most PSI cases spontaneously improved, and four patients (6.7%) showed PSI at the final follow-up. Univariate analysis indicated significant differences between postoperative T1 tilt (9.00 ± 5.17 vs. 5.67 ± 4.02, P = 0.029), UIV tilt (1.94 ± 4.49 vs. -1.00 ± 5.04, P = 0.039), and ΔT1 tilt (4.82 ± 3.99 vs. 2.12 ± 3.77, P = 0.026). Multivariate logistic regression analysis indicated that ΔT1 tilt had a significant positive relationship with PSI occurrence (coefficient = 0.2541, 95% confidence interval [CI]: 0.023 to 0.485, P = 0.0310). This study found no significant differences in the SRS-22 scores at the final follow-up.

CONCLUSIONS

The incidence of PSI for Lenke2 AIS was 28.3% at 1 week postoperatively and 6.7% at the final follow-up. ΔT1 tilt was a risk factor for PSI. Adjustment of the T1 tilt during surgery was considered useful for the prevention of PSI.

Prediction Model for Lumbar Curve Correction After Selective Thoracic Fusion in Lenke 1 and 2 Adolescent Idiopathic Scoliosis

STUDY DESIGN

A retrospective study.

OBJECTIVE

To identify independent risk factors and construct a prediction model for lumbar curve correction (LCC) after selective thoracic fusion (STF) in patients with Lenke 1 and 2 adolescent idiopathic scoliosis (AIS).

SUMMARY OF BACKGROUND DATA

STF has been widely applied to Lenke 1 and 2 AIS patients. However, LCC after STF is still controversial.

METHODS

One hundred twenty-eight patients undergoing STF with at least 2 years of follow-up were included. Cases were divided into a high-LCC group and a low-LCC group according to a rounded-up median of 65%. Forty-nine variables were taken into account. Logistic regression was applied to identify independent predictive factors. A prediction model was established by backward stepwise regression, and its evaluation was implemented on R.

RESULTS

Five parameters showed independent predictive value for low LCC: right shoulder higher before surgery (right shoulder higher versus balanced: odds ratio [OR]=0.244, P =0.014), postoperative Cobb angle of lumbar curve (LC) (OR=1.415, P =0.001, cutoff value=11°), lowest instrumented vertebra (LIV) distal to end vertebra (no vs. yes: OR=4.587, P =0.013), postoperative LIV tilt (OR=0.686, P =0.010, cutoff value=6.85°) and postoperative LIV+1 tilt (OR=1.522, P =0.005, cutoff value=6.25°). The prediction model included 6 variables: lumbar modifier, preoperative shoulder balance, postoperative Cobb angle of LC, LIV position, postoperative LIV tilt, and postoperative LIV+1 tilt. The model evaluation demonstrated satisfactory capability and stability (area under curve=0.890, 10-fold cross-validation accuracy=0.782).

CONCLUSION

Preoperative shoulder balance, Cobb angle of LC, LIV position, postoperative LIV and LIV+1 tilt could be used to prognosticate LCC after STF. A model with solid prediction ability was established, which could further our understanding of LCC and assist in making clinical decisions.

The causal association between type 2 diabetes and spinal stenosis: A Mendelian randomization analysis

Spinal stenosis is a prevalent degenerative spinal disease and one of the main causes of pain and dysfunction in older adults. Substantial evidence indicates a potentially relevant association between type 2 diabetes mellitus (T2DM) and spinal stenosis. However, the causality between these 2 disorders remains unclear. Therefore, we intended to elucidate this relationship using Mendelian Randomization (MR) analysis in this study. Based on genome-wide association study (GWAS) data on T2DM and spinal stenosis, we performed a bidirectional 2-sample MR analysis to evaluate the causality of T2DM and spinal stenosis. We assessed heterogeneity using Cochran's Q statistic and horizontal pleiotropy using the MR-Egger-intercept. "Leave-one-out" analysis was performed to determine the reliability of causal relationships. In addition, we conducted multivariate MR to clarify the direct influence of T2DM on spinal stenosis after accounting for the effect of body mass index (BMI) on spinal stenosis. Our results indicated that Individuals with T2DM had a heightened risk of spinal stenosis (odds ratio [OR]: 1.050; 95% CI: 1.004-1.098, P = .031). Moreover, no reverse causality existed between T2DM and spinal stenosis. The results of the sensitivity analysis suggest that causality is steady and robust. Multivariate MR results demonstrated that the causality of T2DM on spinal stenosis was not related to BMI (OR, 1.047; 95% CI: 1.003-1.093; P = .032). MR analyses demonstrated a possible positive causal relationship between T2DM and spinal stenosis and that this causality was unrelated to BMI.

Monocentric Retrospective Analysis of Clinical Outcomes, Complications, and Adjacent Segment Disease in 507 Patients Undergoing Anterior Cervical Discectomy and Fusion for Degenerative Cervical Myelopathy

BACKGROUND

Degenerative cervical myelopathy (DCM) is a leading cause of nontraumatic spinal cord injury. Surgery aims to arrest neurological decline and improve conditions, but controversies surround risks and benefits in elderly patients, outcomes in mild myelopathy, and the risk of adjacent segment disease (ASD).

METHODS

Retrospective data of patients who underwent anterior cervical discectomy and fusion for DCM in our hospital were collected. Patients were stratified by preoperative modified Japanese Orthopaedic Association (mJOA) (mild, moderate, severe) and age (under 70, over 70). Clinical outcomes, complications, and ASD rate were analyzed. We evaluated the relationship between mJOA recovery rate and the risk of complications and various preoperative parameters.

RESULTS

Five hundred seven consecutive patients were included in the study, with a mean follow-up of 43.52 months (12-71). Improvement in all outcome variables was observed in mild, moderate, and severe myelopathy categories, with elderly patients showing a lower improvement. Except for age, no other variable correlated with mJOA recovery rate. We observed 45 complications (11.1% of patients), with 14 in the U70 group and 31 in the O70 group (P value < 0.001). Age, Charlson comorbidity index, and ASA score were found to be predictors of complications. Fourteen patients (2.8% of total), mean age 54.2, developed radiological and clinical ASD. Most had cranial-level ASD with Pfirmann grade ≥ 2 before index surgery.

CONCLUSIONS

Most myelopathic patients improve after anterior cervical discectomy and fusion. Elderly patients show a lower improvement and higher complication rates than their younger counterparts. ASD rates are low, and younger patients with preexisting cranial level alterations are more susceptible.

Comparison of anterior and posterior approach in the treatment of acute and chronic cervical spinal cord injury: a meta-analysis

Objective

A cervical spinal cord injury (CSCI) is a traumatic catastrophe that often leads to neurological dysfunction. The optimal surgical procedure for the treatment of CSCI remains debatable. The aim of this meta-analysis is to compare the neurological outcomes, complications, and clinical factors between anterior and posterior approach in CSCI treatment.

Methods

We searched PubMed, Embase, Web of Science and Cochrane library from their inceptions to october 2023. Preoperative and postoperative Spinal Injury Association (ASIA) and Japanese Orthopedic Association (JOA) scores, and calculated recovery rates (RRs) were compared between the two strategies, and differences in complication rates, operation time, intraoperative blood loss and length of stay were also analyzed.

Results

A total of five studies containing 613 patients were included, with 320 patients undergoing the anterior approach and 293 patients undergoing the posterior approach. Four of the studies included were retrospective cohort studies of high quality as assessed by the Newcastle Ottawa Scale. Additionally, there was one randomized controlled trial evaluated with the Cochrane Risk of Bias tool. Although both anterior and posterior approaches effectively facilitate spinal decompression and promote good neurological recovery, there was no significant difference in the incidences of neurological dysfunction and complications or other clinical features between the two approaches.

Conclusion

There is no evidence thus far supports one approach over the other. Large-scale randomized controlled studies are warranted to further distinguish these two methods.

Systematic Review Registration

https://www.crd.york.ac.uk/, PROSPERO [CRD42023438831].

Retrospective Analysis of the Efficacy and Safety of Endoscopic Spinal Tuberculosis and Brucellosis Lesion Removal and Posterior Pedicle Lesion Removal, Bone Grafting, Internal Fixation and Surgery Combined with Medical Chemotherapy in the Treatment of Spinal Tuberculosis and Brucellosis

Objective

To evaluate the clinical effectiveness of endoscopic removal of spinal infections and posterior pedicle surgery, including bone grafting, fixation, and chemotherapy, and to outline preventive strategies for complications, offering guidance for clinical practice.

Methods

128 spinal infectious disease patients (2018-2022) were categorized into Group A (endoscopic removal, n=44) and Group B (posterior pedicle removal+bone grafting+fixation, n=84). Pre-surgery, all received quadruple antibiotic therapy. Metrics tracked: operation time, blood loss, drainage, recovery, stay, transfusion, complications, and pre/post-surgery VAS, ODI, ESR, CRP, PCT, D-dimer, NLR, Hb, albumin.

Results

(1) Preoperative data: There were no statistically significant differences in age, gender, body mass index, involved segments, past medical history (cardiovascular and cerebrovascular diseases, respiratory diseases, endocrine system diseases, metabolic diseases and tuberculosis), smoking history, preoperative erythrocyte sedimentation rate, C-reactive protein, procalcitonin, D-dimer, lymphocyte and neutrophil-lymphocyte ratio, hemoglobin, total protein, waist VAS score and waist ODI score (P>0.05). (2) The main postoperative indexes were significantly lower than those of group B at the last follow-up at 3 months and the last follow-up in group A, and the difference was significant (P<0.05), the hemoglobin and total protein in group A were significantly higher than those in group B at the last postoperative follow-up (P<0.05), and the recurrence rate in group B was significantly higher than that in group A, and the difference was significant (P=0.048). (3) Postoperative secondary indicators: the amount of blood transfusion in group A was significantly lower than that in group B, and the difference between the two groups was statistically significant (P<0.05), while the operation time, intraoperative blood loss and postoperative hospital stay in group A were significantly smaller than those in group B, and the difference between the two groups was statistically significant (P<0.05).

Conclusion

Endoscopic lesion removal for spinal infections achieves similar safety to posterior pedicle surgery, with shorter operation time, less blood loss, lower recurrence, and reduced drainage. It enhances ESR, spine function, and pain relief, meriting promotion.

Evaluation of the use of tranexamic acid in the postoperative period in patients with scoliosis undergoing posterior fusion

Scoliosis is the most prevalent type of spinal deformity, with a 2-3% prevalence in the general population. Moreover, surgery for scoliotic deformity may result in severe blood loss and, consequently, the need for blood transfusions, thereby increasing surgical morbidity and the rate of complications. Several antifibrinolytic drugs, such as tranexamic acid, have been regarded as safe and effective options for reducing blood loss. Therefore, the present study aimed to analyse the effectiveness of this drug for controlling bleeding when used intraoperatively and in the first 48 h after surgery. A prospective randomized study of a cohort of patients included in a mass event for scoliosis treatment using PSF was performed. Twenty-eight patients were analysed and divided into two groups: 14 patients were selected for intraoperative and postoperative use of tranexamic acid (TXA), and the other 14 were selected only during the intraoperative period. The drainage bleeding rate, length of hospital stay, number of transfused blood units, and rate of adverse clinical effects were compared. All the patients involved had similar numbers of fusion levels addressed and similar scoliosis profiles. The postoperative bleeding rate through the drain did not significantly differ between the two groups (p > 0.05). There was no significant difference in the number of transfused blood units between the groups (p = 0.473); however, in absolute numbers, patients in the control group received more transfusions. The length of hospital stay was fairly similar between the groups, with no statistically significant difference. Furthermore, the groups had similar adverse effects (p = 0.440), with the exception of nausea and vomiting, which were twice as common in the TXA group postoperatively than in the control group. No significant differences were found in the use of TXA during the first 48 postoperative hours or in postoperative outcomes.

The application of gradually expanding pedicle technology in the placement of screws in thinner pedicle of patients with idiopathic scoliosis

Objective

To propose a technique of gradual expansion of pedicle diameter to place screws on the thinner pedicle that is difficult to place screws in scoliosis orthopedic surgery, in order to place thicker pedicle screws in the premise of good safety to achieve good stability and orthopaedic effect.

Methods

The authors reviewed that 36 patients with Adolescent idiopathic scoliosis (AIS) (20 females, 16 males) in our department from June 2020 to March 2024 underwent posterior spinal correction and internal fixation were enrolled in the present study. 194 pedicles had narrower diameter ranging from 0 mm to 4.5 mm. After analysis, 155 pedicles (internal diameter: 2.5 mm-4.5 mm) were treated with gradually expanding pedicles technology. The angle between the inserted screws and the upper endplate of the vertebral body was measured 1 week after operation and 3 months after operation to evaluate the placement of the screws after pedicle expansion.

Results

All operations were completed without dura mater rupture, nerve root injury, infection and poor incision healing. There was no screw breaking or screw pull-out in DR film at 3 months after operation compared with 1 week after operation. There was no significant difference in the angle between screw and upper endplate measured by the three observers at 3 months and 1 week after operation (Wilcoxon's signed rank test, p > 0.05). In the measurement at 1 week or 3 months after operation, there was no statistically significant difference among the three observers. There is a good consistency between the observers (Cronbach's alpha > 0.80).

Conclusion

In AIS patients, the thinner pedicle with a diameter range of 2.5 mm to 4.5 mm can be safely inserted with relatively thicker pedicle screws after gradually expanding pedicle technology.

A critical appraisal of ferroptosis in Alzheimer's and Parkinson's disease: new insights into emerging mechanisms and therapeutic targets

Neurodegenerative diseases represent a pressing global health challenge, and the identification of novel mechanisms underlying their pathogenesis is of utmost importance. Ferroptosis, a non-apoptotic form of regulated cell death characterized by iron-dependent lipid peroxidation, has emerged as a pivotal player in the pathogenesis of neurodegenerative diseases. This review delves into the discovery of ferroptosis, the critical players involved, and their intricate role in the underlying mechanisms of neurodegeneration, with an emphasis on Alzheimer's and Parkinson's diseases. We critically appraise unsolved mechanistic links involved in the initiation and propagation of ferroptosis, such as a signaling cascade resulting in the de-repression of lipoxygenase translation and the role played by mitochondrial voltage-dependent anionic channels in iron homeostasis. Particular attention is given to the dual role of heme oxygenase in ferroptosis, which may be linked to the non-specific activity of P450 reductase in the endoplasmic reticulum. Despite the limited knowledge of ferroptosis initiation and progression in neurodegeneration, Nrf2/Bach1 target genes have emerged as crucial defenders in anti-ferroptotic pathways. The activation of Nrf2 and the inhibition of Bach1 can counteract ferroptosis and present a promising avenue for future therapeutic interventions targeting ferroptosis in neurodegenerative diseases.

Coronal decompensation following thoracic vertebral body tethering in idiopathic scoliosis

PURPOSE

Post-operative coronal decompensation (CD) continues to be a challenge in the treatment of adolescent idiopathic scoliosis (AIS). CD following selective spinal fusion has been studied. However, there is currently little information regarding CD following Vertebral Body Tethering (VBT). Thus, the goal of this study is to better understand the incidence and risk factors for CD after VBT.

METHODS

Retrospective review of a prospective multicenter database was used for analysis. Inclusion criteria were patients undergoing thoracic VBT, a minimum 2-year follow-up, LIV was L1 or above, skeletally immature (Risser ≤ 1), and available preoperative and final follow-up AP and lateral upright radiographs. Radiographic parameters including major and minor Cobb angles, curve type, LIV tilt/translation, L4 tilt, and coronal balance were measured. CD was defined as the distance between C7PL and CSVL > 2 cm. Multiple logistic regression model was used to identify significant predictors of CD.

RESULTS

Out of 136 patients undergoing VBT, 94 patients (86 female and 6 male) met the inclusion criteria. The mean age at surgery was 12.1 (9-16) and mean follow-up period was 3.4 years (2-5 years). Major and minor curves, AVR, coronal balance, LIV translation, LIV tilt, L4 tilt were significantly improved after surgery. CD occurred in 11% at final follow-up. Lenke 1A-R (24%) and 1C (26%) had greater incidence of CD compared to 1A-L (4%), 2 (0%), and 3 (0%). LIV selection was not associated with CD. Multivariate logistic regression analysis yielded 1A-R and 1C curves as a predictor of CD with the odds ratio being 17.0.

CONCLUSION

CD occurred in 11% of our thoracic VBT patients. Lenke 1A-R and 1C curve types were predictors for CD in patients treated with VBT. There were no other preoperative predictors associated with CD.

Lowest instrumented vertebrae in early onset scoliosis: is there a role for a more selective approach?

PURPOSE

This purpose of this study was to assess the impact of patient and implant characteristics on LIV selection in ambulatory children with EOS and to assess the relationship between the touched vertebrae (TV), the last substantially touched vertebrae (LSTV), the stable vertebrae (SV), the sagittal stable vertebrae (SSV), and the LIV.

METHODS

A multicenter pediatric spine database was queried for patients ages 2-10 years treated by growth friendly instrumentation with at least 2-year follow up. The relationship between the LIV and preoperative spinal height, curve magnitude, and implant type were assessed. The relationships between the TV, LSTV, SV, SSV, and the LIV were also evaluated.

RESULTS

Overall, 281 patients met inclusion criteria. The LIV was at L3 or below in most patients with a lumbar LIV: L1 (9.2%), L2 (20.2%), L3 (40.9%), L4 (29.5%). Smaller T1 - T12 length was associated with more caudal LIV selection (p = 0.001). Larger curve magnitudes were similarly associated with more caudal LIV selection (p = < 0.0001). Implant type was not associated with LIV selection (p = 0.32) including MCGR actuator length (p = 0.829). The LIV was caudal to the TV in 78% of patients with a TV at L2 or above compared to only 17% of patients with a TV at L3 or below (p < 0.0001).

CONCLUSIONS

Most EOS patients have an LIV of L3 or below and display TV-LIV and LSTV-LIV incongruence. These findings suggest that at the end of treatment, EOS patients rarely have the potential for selective thoracic fusion. Further work is necessary to assess the potential for a more selective approach to LIV selection in EOS.

LEVEL OF EVIDENCE

III.

A comparison of transforaminal lumbar interbody fusion (TLIF) cage material on fusion rates: A systematic review and network meta-analysis

Background

A wide variety of materials are used for lumbar interbody fusion, but there is no unified consensus on the superiority of one material over another. The aim of this systematic review and network meta-analysis (NMA) is to compare and rank the various TLIF interbody materials based on fusion rates.

Methods

We queried PubMed, EMBASE and Scopus from inception until August 2023, in which 2135 studies were identified. Inclusion criteria were applied based on the PRISMA guidelines. The fusion assessment employed the Bridwell's criteria with a length of follow-up of at least 12 months. The NMA was conducted to compare multiple approaches from multiple studies using the frequentist framework with STATA16.

Results

In total, 13 TLIF studies involving 1919 patients with 1981 lumbar interbody levels fulfilled our eligibility criteria. Seven different cage materials were utilized: polyetheretherketone (PEEK, as the reference), allograft, autograft, PEEK with titanium coating (TiPEEK), titanium, carbon/carbon fiber reinforced polymer (CFRP) and 3D-printed titanium. The average patient age was 60.9 (SD = 7.5) years old. When compared to PEEK, the other six materials did not have a significantly different rate of lumbar fusion. However, the SUCRA number of the 3D-printed titanium, TiPEEK, Ti, allograft, autograft, CFRP, and PEEK were 0.8, 0.6, 0.5, 0.5, 0.4, 0.4, and 0.3 consecutively.

Conclusions

Based on a network meta-analysis within the confines of our clinical study, 3D-printed titanium interbody cage may promote the highest success rate of fusion while PEEK may be the material with the least success rate of fusion in TLIF.

Comparison of Anterior Cervical Decompression and Fusion and Posterior Laminoplasty for Four-Segment Cervical Spondylotic Myelopathy: Clinical and Radiographic Outcomes

BACKGROUND

 Although anterior or posterior surgery for cervical spondylotic myelopathy (CSM) has been extensively studied, the choice of anterior or posterior approach in four-segment CSM remains poorly studied and controversial. We compared the clinical and radiographic outcomes of four-segment CSM by posterior laminoplasty (LAMP) and anterior cervical decompression fusion (ACDF) to further explore the merits and demerits of ACDF and LAMP for four-segment CSM in this study.

METHODS

 Patients with four-segment CSM who underwent ACDF or LAMP between January 2016 and June 2019 were retrospectively analyzed. We compared the preoperative and postoperative cervical Japanese Orthopaedic Association (JOA) scores, neck disability index (NDI), neck pain visual analog scale (VAS) score, sagittal vertical axis, cervical lordosis (CL), and range of motion.

RESULTS

 There were 47 and 79 patients in the ACDF and LAMP groups, respectively. Patients in the ACDF group had a significantly longer surgical time and lower estimated blood loss and length of stay than those in the LAMP group. There was no significant difference in the JOA, NDI, or neck pain VAS scores between the two groups preoperatively, but the NDI and neck pain VAS scores in the ACDF group were significantly lower than those in the LAMP group at the final follow-up. The preoperative C2-C7 Cobb angle of the ACDF group was significantly lower than that of the LAMP group but there was no significant difference between the two groups postoperatively. The improvement of C2-C7 Cobb angle (∆C2-C7 Cobb angle) in the ACDF group was significantly higher than that in the LAMP group. This indicated that ACDF can improve CL better than LAMP. The linear regression analysis revealed the ∆C2-C7 Cobb angle was negatively correlated with the final follow-up neck pain VAS scores and NDI. This indicated that patients with better improvement of CL may have a better prognosis.

CONCLUSIONS

 Although both ACDF and LAMP surgeries are effective for four-segment CSM, ACDF can better improve CL and neck pain. For patients with poor CL, we suggest ACDF when both approaches are feasible.

Decompression alone or decompression with fusion for lumbar spinal stenosis: five-year clinical results from a randomized clinical trial

Aims

We compared decompression alone to decompression with fusion surgery for lumbar spinal stenosis, with or without degenerative spondylolisthesis (DS). The aim was to evaluate if five-year outcomes differed between the groups. The two-year results from the same trial revealed no differences.

Methods

The Swedish Spinal Stenosis Study was a multicentre randomized controlled trial with recruitment from September 2006 to February 2012. A total of 247 patients with one- or two-level central lumbar spinal stenosis, stratified by the presence of DS, were randomized to decompression alone or decompression with fusion. The five-year Oswestry Disability Index (ODI) was the primary outcome. Secondary outcomes were the EuroQol five-dimension questionnaire (EQ-5D), visual analogue scales for back and leg pain, and patient-reported satisfaction, decreased pain, and increased walking distance. The reoperation rate was recorded.

Results

Five-year follow-up was completed by 213 (95%) of the eligible patients (mean age 67 years; 155 female (67%)). After five years, ODI was similar irrespective of treatment, with a mean of 25 (SD 18) for decompression alone and 28 (SD 22) for decompression with fusion (p = 0.226). Mean EQ-5D was higher for decompression alone than for fusion (0.69 (SD 0.28) vs 0.59 (SD 0.34); p = 0.027). In the no-DS subset, fewer patients reported decreased leg pain after fusion (58%) than with decompression alone (80%) (relative risk (RR) 0.71 (95% confidence interval (CI) 0.53 to 0.97). The frequency of subsequent spinal surgery was 24% for decompression with fusion and 22% for decompression alone (RR 1.1 (95% CI 0.69 to 1.8)).

Conclusion

Adding fusion to decompression in spinal stenosis surgery, with or without spondylolisthesis, does not improve the five-year ODI, which is consistent with our two-year report. Three secondary outcomes that did not differ at two years favoured decompression alone at five years. Our results support decompression alone as the preferred method for operating on spinal stenosis.

Mechanisms and therapeutic targets of ferroptosis: Implications for nanomedicine design

Ferroptosis is a nonapoptotic form of cell death and differs considerably from the well-known forms of cell death in terms of cell morphology, genetics, and biochemistry. The three primary pathways for cell ferroptosis are system Xc-/glutathione peroxidase 4 (GPX4), lipid metabolism, and ferric metabolism. Since the discovery of ferroptosis, mounting evidence has revealed its critical regulatory role in several diseases, especially as a novel potential target for cancer therapy, thereby attracting increasing attention in the fields of tumor biology and anti-tumor therapy. Accordingly, broad prospects exist for identifying ferroptosis as a potential therapeutic target. In this review, we aimed to systematically summarize the activation and defense mechanisms of ferroptosis, highlight the therapeutic targets, and discuss the design of nanomedicines for ferroptosis regulation. In addition, we opted to present the advantages and disadvantages of current ferroptosis research and provide an optimistic vision of future directions in related fields. Overall, we aim to provide new ideas for further ferroptosis research and inspire new strategies for disease diagnosis and treatment.

Modified Tap-drilling Technique for Mid-cervical Pedicle Screw Placement: A Case Series of 473 Consecutive Screws

STUDY DESIGN

Retrospective cohort study.

OBJECTION

To report our modified tap-drilling technique for mid-cervical pedicle screw placement and to evaluate its safety and accuracy.

SUMMARY OF BACKGROUND DATA

Cervical pedicle screw fixation, which provides a strong stabilization, has been a major concern due to the potential risks to neurovascular structures despite its increasing use. Several insertion techniques have been described so far to improve the cervical pedicle screw placement accuracy.

METHODS

This study retrospectively reviewed patients who underwent mid-cervical (C3-C6) pedicle screw fixation between September 2005 and September 2020. Laminectomy, laminoforaminotomy, or notch-referred anatomic landmark methods were used to adjust the entry point and the direction of the screws. After the cortical bone was removed at the entry point with a diamond burr, the cancellous bone was slowly drilled with a hand drill starting from 8 to 10 millimeters in length. Then, all of the bone walls were checked with a ball-tip probe to determine if there was any breach. The procedure was repeated several times. After completing the drilling, the screw was inserted without tapping. The breach rate of pedicle screws was analyzed on postoperative computed tomography scans.

RESULTS

A total of 473 mid-cervical pedicle screws were placed in 122 consecutive patients. No navigation or computer-assisted system was used, and the first 2 authors inserted all of the screws. All patients completed the surgery, and no evident intraoperative complications occurred. Postoperative CT scans were obtained for 405 screws. Although deviation was observed for 131 pedicle screws, a critical deviation was observed for only 25 pedicle screws.

CONCLUSIONS

Cervical pedicle screw insertion is a risky but applicable technique. Checking all of the bone walls with a ball-tip probe before gradually advancing the hand drill in small amounts, as presented in this article, may lead to the safe and effective placement of cervical pedicle screws.

Ferroptosis inhibitor improves outcome after early and delayed treatment in mild spinal cord injury

We show that redox active iron can induce a regulated form of non-apoptotic cell death and tissue damage called ferroptosis that can contribute to secondary damage and functional loss in the acute and chronic periods after spinal cord injury (SCI) in young, adult, female mice. Phagocytosis of red blood cells at sites of hemorrhage is the main source of iron derived from hemoglobin after SCI. Expression of hemeoxygenase-1 that induces release of iron from heme, is increased in spinal cord macrophages 7 days after injury. While iron is stored safely in ferritin in the injured spinal cord, it can, however, be released by NCOA4-mediated shuttling of ferritin to autophagosomes for degradation (ferritinophagy). This leads to the release of redox active iron that can cause free radical damage. Expression of NCOA4 is increased after SCI, mainly in macrophages. Increase in the ratio of redox active ferrous (Fe2+) to ferric iron (Fe3+) is also detected after SCI by capillary electrophoresis inductively coupled mass spectrometry. These changes are accompanied by other hallmarks of ferroptosis, i.e., deficiency in various elements of the antioxidant glutathione (GSH) pathway. We also detect increases in enzymes that repair membrane lipids (ACSL4 and LPCAT3) and thus promote on-going ferroptosis. These changes are associated with increased levels of 4-hydroxynonenal (4-HNE), a toxic lipid peroxidation product. Mice with mild SCI (30 kdyne force) treated with the ferroptosis inhibitor (UAMC-3203-HCL) either early or delayed times after injury showed improvement in locomotor recovery and secondary damage. Cerebrospinal fluid and serum samples from human SCI cases show evidence of increased iron storage (ferritin), and other iron related molecules, and reduction in GSH. Collectively, these data suggest that ferroptosis contributes to secondary damage after SCI and highlights the possible use of ferroptosis inhibitors to treat SCI.

Advancements in osteosarcoma management: integrating immune microenvironment insights with immunotherapeutic strategies

Osteosarcoma, a malignant bone tumor predominantly affecting children and adolescents, presents significant therapeutic challenges, particularly in metastatic or recurrent cases. Conventional surgical and chemotherapeutic approaches have achieved partial therapeutic efficacy; however, the prognosis for long-term survival remains bleak. Recent studies have highlighted the imperative for a comprehensive exploration of the osteosarcoma immune microenvironment, focusing on the integration of diverse immunotherapeutic strategies-including immune checkpoint inhibitors, tumor microenvironment modulators, cytokine therapies, tumor antigen-specific interventions, cancer vaccines, cellular therapies, and antibody-based treatments-that are directly pertinent to modulating this intricate microenvironment. By targeting tumor cells, modulating the tumor microenvironment, and activating host immune responses, these innovative approaches have demonstrated substantial potential in enhancing the effectiveness of osteosarcoma treatments. Although most of these novel strategies are still in research or clinical trial phases, they have already demonstrated significant potential for individuals with osteosarcoma, suggesting the possibility of developing new, more personalized and effective treatment options. This review aims to provide a comprehensive overview of the current advancements in osteosarcoma immunotherapy, emphasizing the significance of integrating various immunotherapeutic methods to optimize therapeutic outcomes. Additionally, it underscores the imperative for subsequent research to further investigate the intricate interactions between the tumor microenvironment and the immune system, aiming to devise more effective treatment strategies. The present review comprehensively addresses the landscape of osteosarcoma immunotherapy, delineating crucial scientific concerns and clinical challenges, thereby outlining potential research directions.

The microRNA Let-7 and its exosomal form: Epigenetic regulators of gynecological cancers

Many types of gynecological cancer (GC) are often silent until they reach an advanced stage, and are therefore often diagnosed too late for effective treatment. Hence, there is a real need for more efficient diagnosis and treatment for patients with GC. During recent years, researchers have increasingly studied the impact of microRNAs cancer development, leading to a number of applications in detection and treatment. MicroRNAs are a particular group of tiny RNA molecules that regulate regular gene expression by affecting the translation process. The downregulation of numerous miRNAs has been observed in human malignancies. Let-7 is an example of a miRNA that controls cellular processes as well as signaling cascades to affect post-transcriptional gene expression. Recent research supports the hypothesis that enhancing let-7 expression in those cancers where it is downregulated may be a potential treatment option. Exosomes are tiny vesicles that move through body fluids and can include components like miRNAs (including let-7) that are important for communication between cells. Studies proved that exosomes are able to enhance tumor growth, angiogenesis, chemoresistance, metastasis, and immune evasion, thus suggesting their importance in GC management.

Both hemoglobin and hemin cause damage to retinal pigment epithelium through the iron ion accumulation

Subretinal hemorrhages result in poor vision and visual field defects. During hemorrhage, several potentially toxic substances are released from iron-based hemoglobin and hemin, inducing cellular damage, the detailed mechanisms of which remain unknown. We examined the effects of excess intracellular iron on retinal pigment epithelial (RPE) cells. A Fe2+ probe, SiRhoNox-1 was used to investigate Fe2+ accumulation after treatment with hemoglobin or hemin in the human RPE cell line ARPE-19. We also evaluated the production of reactive oxygen species (ROS) and lipid peroxidation. Furthermore, the protective effect of-an iron chelator, 2,2'-bipyridyl (BP), and ferrostatin-1 (Fer-1) on the cell damage, was evaluated. Fe2+ accumulation increased in the hemoglobin- or hemin-treated groups, as well as intracellular ROS production and lipid peroxidation. In contrast, BP treatment suppressed RPE cell death, ROS production, and lipid peroxidation. Pretreatment with Fer-1 ameliorated cell death in a concentration-dependent manner and suppressed ROS production and lipid peroxidation. Taken together, these findings indicate that hemoglobin and hemin, as well as subretinal hemorrhage, may induce RPE cell damage and visual dysfunction via intracellular iron accumulation.

Diabetes Mellitus and Poor Glycemic Control Are Associated With a Higher Risk of Lumbar Spinal Stenosis: An Analysis of a Large Nationwide Database

STUDY DESIGN

A large-scale retrospective case-control study.

OBJECTIVE

Examine diabetes as a risk factor for lumbar spinal stenosis (LSS) development and evaluate the impact of diabetes duration, glycemic control, and associated complications on this risk.

SUMMARY OF BACKGROUND DATA

Diabetes mellitus, a multiorgan disorder impacting various connective tissues, induces histological changes in spinal structures, particularly the ligamentum flavum. While clinical studies suggest a higher incidence of LSS in diabetic patients, substantial epidemiological research on the likelihood of LSS diagnosis in individuals with diabetes is scarce.

MATERIALS AND METHODS

Using nationwide data, a total of 49,576 patients diagnosed with LSS based on International Classification of Diseases-10 codes were matched with controls of the same number based on age and sex. Employing a multivariable logistic regression model, the study assessed for the association between spinal stenosis and diabetes, while adjusting for confounders.

RESULTS

We found a higher likelihood of LSS diagnosis in diabetic patients [odds ratio (OR) 1.39, 95% CI: 1.36 - 1.43, P <0.001]. Those with hemoglobin A1c ≥7% and ≥1 diabetes-related complication also had an elevated likelihood (OR: 1.19, 95% CI: 1.08-1.31, P =0.001). Prolonged diabetes exposure increased the risk. Diabetes diagnosis reduced median survival by around 4.5 years for both stenosis and nonstenosis patients; spinal stenosis diagnosis alone minimally impacted survival. Relative to individuals diagnosed with diabetes mellitus at the age of 65 or older, the OR for developing LSS were 1.22 (95% CI: 1.18-1.27, P <0.001) when DM was diagnosed at 50 to 65 years old and 1.67 (95% CI: 1.56-1.79, P <0.001) for those under 50 years old. Multivariate analysis revealed a significantly increased risk of all-cause mortality in patients with DM and spinal stenosis (hazard ratio: 1.36, 95% CI: 1.29-1.44, P <0.001) and those with DM without stenosis (hazard ratio: 1.49, 95% CI: 1.41-1.57, P <0.001) compared with controls.

CONCLUSIONS

Diabetic patients with prolonged disease, poor glycemic control, and diabetes-related complications face an elevated risk of developing LSS. Recognizing the reciprocal adverse relationship between these conditions is crucial in clinical practice and designing public health measures for managing both conditions.

LEVEL OF EVIDENCE

4.

The cost-utility of intraoperative tranexamic acid in adult spinal deformity patients undergoing long posterior spinal fusion

PURPOSE

This study aims to evaluate the cost-utility of intraoperative tranexamic acid (TXA) in adult spinal deformity (ASD) patients undergoing long posterior (≥ 5 vertebral levels) spinal fusion.

METHODS

A decision-analysis model was built for a hypothetical 60-year-old adult patient with spinal deformity undergoing long posterior spinal fusion. A comprehensive review of the literature was performed to obtain event probabilities, costs and health utilities at each node. Health utilities were utilized to calculate Quality-Adjusted Life Years (QALYs). A base-case analysis was carried out to obtain the incremental cost and effectiveness of intraoperative TXA. Probabilistic sensitivity analysis was performed to evaluate uncertainty in our model and obtain mean incremental costs, effectiveness, and net monetary benefits. One-way sensitivity analyses were also performed to identify the variables with the most impact on our model.

RESULTS

Use of intraoperative TXA was the favored strategy in 88% of the iterations. The mean incremental utility ratio for using intraoperative TXA demonstrated higher benefit and lower cost while being lower than the willingness-to-pay threshold set at $50,000 per quality adjusted life years. Use of intraoperative TXA was associated with a mean incremental net monetary benefit (INMB) of $3743 (95% CI 3492-3995). One-way sensitivity analysis reported cost of blood transfusions due to post-operative anemia to be a major driver of cost-utility analysis.

CONCLUSION

Use of intraoperative TXAs is a cost-effective strategy to reduce overall perioperative costs related to post-operative blood transfusions. Administration of intraoperative TXA should be considered for long fusions in ASD population when not explicitly contra-indicated due to patient factors.

Fusion Surgery for Lumbar Spondylolisthesis: A Systematic Review with Network Meta-Analysis of Randomized Controlled Trials

OBJECTIVE

This study aimed to systematically evaluate the optimal surgical fusion approach for lumbar spondylolisthesis, to provide the latest and most reliable evidence for future clinical practice.

METHODS

A comprehensive search of the PubMed, Ovid-Embase, Web of Science, Cochrane, and Scopus databases was conducted from inception to September 1, 2023, to identify relevant records. Two independent reviewers performed the literature screening, data extraction, and assessment of study quality.

RESULTS

Fifteen randomized controlled trials involving 892 patients met the inclusion criteria. The network evidence plot showed that posterolateral fusion and posterior lumbar interbody fusion (PLIF) were the most used fusion techniques. The network meta-analysis results revealed that minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) had a significantly greater improvement in the Oswestry Disability Index (ODI) compared to endoscopic-TLIF, while PLIF had a significantly better fusion effect than posterolateral fusion. Furthermore, no statistically significant differences were observed between other fusion surgeries in terms of improving ODI, fusion rate, complications, or the improvement of visual analog scale-low back pain. The surface under the cumulative ranking curve results indicated that MIS-TLIF had the greatest potential for improving ODI, visual analog scale-low back pain, and complications, while PLIF had the greatest potential for increasing fusion rates. However, the existing selection bias, measurement bias, reporting bias, and publication bias may have reduced the reliability of the meta-analysis results.

CONCLUSIONS

Among the various fusion surgeries for lumbar spondylolisthesis, MIS-TLIF appears to provide the greatest benefit to patients. However, more high-quality, large-scale studies are needed to further investigate the treatment efficacy of different fusion surgeries for lumbar spondylolisthesis.

Modification to the placement of the navigation reference frame in posterior corrective fusion of spinal deformity with myelomeningocele: a series of 6 cases

To show a modified placement of the navigation reference frame in posterior corrective fusion of spinal deformity with myelomeningocele. This was a retrospective, single-surgeon case series, and IRB-approved study. Six consecutive patients (one male and five females) who were diagnosed with spinal deformity with myelomeningocele underwent posterior corrective fusion surgery from the upper thoracic spine to the pelvis with preoperative computed tomography navigation (pCTN). At the level of the spina bifida, where posterior elements such as the spinous process were missing, the reference frame of the pCTN was placed on the flipped lamina or pedicles, and a pedicle screw (PS) or iliac screw (IS) was inserted. Screw deviation was investigated by using postoperative CT. A total of 55 screws were placed at the spina bifida level and pelvis. Of these, 12 ISs were placed on each side in each case. The screws placed using the pCTN were not reinserted or removed intraoperatively or postoperatively. However, only one PS was found to have perforated the spinal canal on postoperative CT but was left in place because it caused no neurological problem. By modifying the placement of the reference frame, such as placing it on the flipped lamina or pedicles, pCTN could be used even at the levels of the spina bifida, where the posterior elements are missing, to accurately place PSs and various types of ISs.

Incidence and risk factors of proximal junctional kyphosis in adolescent idiopathic scoliosis after correction surgery: a meta-analysis and systematic review

AIM

To analyze the risk factors of proximal junctional kyphosis (PJK) after correction surgery in patients with adolescent idiopathic scoliosis (AIS).

METHODS

PubMed, Medline, Embase, Cochrane Library, Web of Science, CNKI, and EMCC databases were searched for retrospective studies utilizing all AIS patients with PJK after corrective surgery to collect preoperative, postoperative, and follow-up imaging parameters, including thoracic kyphosis (TK), lumbar lordosis (LL), proximal junctional angle (PJA), the sagittal vertical axis (SVA), pelvic incidence (PI), pelvic tilt (PT), pelvic incidence-lumbar lordosis (PI-LL), sacral slope (SS), rod contour angle (RCA) and upper instrumented vertebra (UIV).

RESULTS

Nineteen retrospective studies were included in this meta-analysis, including 550 patients in the intervention group and 3456 patients in the control group. Overall, sex (OR 1.40, 95% CI (1.08, 1.83), P = 0.01), larger preoperative TK (WMD 6.82, 95% CI (5.48, 8.16), P < 0.00001), larger follow-up TK (WMD 8.96, 95% CI (5.62, 12.30), P < 0.00001), larger postoperative LL (WMD 2.31, 95% CI (0.91, 3.71), P = 0.001), larger follow-up LL (WMD 2.51, 95% CI (1.19, 3.84), P = 0.0002), great change in LL (WMD - 2.72, 95% CI (- 4.69, - 0.76), P = 0.006), larger postoperative PJA (WMD 4.94, 95% CI (3.62, 6.26), P < 0.00001), larger follow-up PJA (WMD 13.39, 95% CI (11.09, 15.69), P < 0.00001), larger postoperative PI-LL (WMD - 9.57, 95% CI (- 17.42, - 1.71), P = 0.02), larger follow-up PI-LL (WMD - 12.62, 95% CI (- 17.62, - 7.62), P < 0.00001), larger preoperative SVA (WMD 0.73, 95% CI (0.26, 1.19), P = 0.002), larger preoperative SS (WMD - 3.43, 95% CI (- 4.71, - 2.14), P < 0.00001), RCA (WMD 1.66, 95% CI (0.48, 2.84), P = 0.006) were identified as risk factors for PJK in patients with AIS. For patients with Lenke 5 AIS, larger preoperative TK (WMD 7.85, 95% CI (5.69, 10.00), P < 0.00001), larger postoperative TK (WMD 9.66, 95% CI (1.06, 18.26), P = 0.03, larger follow-up TK (WMD 11.92, 95% CI (6.99, 16.86), P < 0.00001, larger preoperative PJA (WMD 0.72, 95% CI (0.03, 1.41), P = 0.04, larger postoperative PJA (WMD 5.54, 95% CI (3.57, 7.52), P < 0.00001), larger follow-up PJA (WMD 12.42, 95% CI 9.24, 15.60), P < 0.00001, larger follow-up SVA (WMD 0.07, 95% CI (- 0.46, 0.60), P = 0.04), larger preoperative PT (WMD - 3.04, 95% CI (- 5.27, - 0.81), P = 0.008, larger follow-up PT (WMD - 3.69, 95% CI (- 6.66, - 0.72), P = 0.02) were identified as risk factors for PJK.

CONCLUSION

Following corrective surgery, 19% of AIS patients experienced PJK, with Lenke 5 contributing to 25%. Prior and post-op measurements play significant roles in predicting PJK occurrence; thus, meticulous, personalized preoperative planning is crucial. This includes considering individualized treatments based on the Lenke classification as our future evaluation standard.

Unraveling molecular signatures in rare bone tumors and navigating the cancer pathway landscapes for targeted therapeutics

Rare cancers (RCs), which account for over 20% of cancer cases, face significant research and treatment challenges due to their limited prevalence. This results in suboptimal outcomes compared to more common malignancies. Rare bone tumors (RBTs) constitute 5-10% of rare cancer cases and pose unique diagnostic complexities. The therapeutic potential of anti-cancer drugs for RBTs remains largely unexplored. Identifying molecular alterations in cancer-related genes and their associated pathways is essential for precision medicine in RBTs. Small molecule inhibitors and monoclonal antibodies targeting specific RBT-associated proteins show promise. Ongoing clinical trials aim to define RBT biomarkers, subtypes, and optimal treatment contexts, including combination therapies and immunotherapeutic agents. This review addresses the challenges in diagnosing, treating, and studying RBTs, shedding light on the current state of RBT biomarkers, potential therapeutic targets, and promising inhibitors. Rare cancers demand attention and innovative solutions to improve clinical outcomes.

Posterior Approach With Osteotomized Debridement Versus Combined Anterior and Posterior Approach in Treating Thoracolumbar Tuberculosis: A Retrospective Cohort Study

STUDY DESIGN

Retrospective cohort.

OBJECTIVES

To compare outcomes of posterior osteotomized debridement (OD) with combined anterior and posterior approach (AP) in treating thoracolumbar tuberculosis (TB).

METHODS

This study reviewed 178 patients who were diagnosed as active thoracolumbar TB and surgically treated in our center. One hundred and two patients underwent posterior OD, interbody fusion with titanium mesh cage (TMC), and instrumentation (group A). Seventy-six patients underwent one-stage posterior instrumentation, anterior debridement, and interbody fusion with TMC (group B). Patients' clinical outcomes were compared between the 2 groups.

RESULTS

Erythrocyte sedimentation rate and C-reactive protein in all patients returned to normal levels within 3 months after surgery, and no recurrence occurred during the follow-up. Compared with AP approach, OD surgery was less invasive and with a lower cost (¥ 70 581 ± 17 645 vs ¥ 87 600 ± 27 328; P < .05). Patients treated by OD showed more significant improvements in Visual Analog Scale (VAS) and Oswestry Disability Index (ODI) than those treated by AP approach 3 months postoperatively (VAS: 3.0 ± .7 vs 3.7 ± .9; ODI: 14.7 ± 4.4 vs 20.6 ± 4.6). Two groups showed similar postoperative kyphosis correction and final follow-up correction loss (P = .361 and P = .162, respectively). The OD method had a lower complication rate than AP approach (9.8% [10/102] vs 35.5% [27/76]; P < .05).

CONCLUSIONS

Posterior OD is effective in treating active thoracolumbar TB. Compared with traditional AP approach, OD surgery has less surgical invasiveness, lower complication rate, and shorter fusion time.

An Algorithmic Roadmap for the Surgical Management of Degenerative Cervical Myelopathy: A Narrative Review

Degenerative cervical myelopathy (DCM) is a leading cause of disability, and its surgical management is crucial for improving patient neurological outcomes. Given the varied presentations and severities of DCM, treatment options are diverse. Surgeons often face challenges in selecting the most appropriate surgical approach because there is no universally correct answer. This narrative review aimed to aid the decision-making process in treating DCM by presenting a structured treatment algorithm. The authors categorized surgical scenarios based on an algorithm, outlining suitable treatment methods for each case. Four primary scenarios were identified based on the number of levels requiring surgery and K-line status: (1) K-line (+) and ≤3 levels, (2) K-line (+) and ≥3 levels, (3) K-line (-) and ≤3 levels, and (4) K-line (-) and ≥3 levels. This categorization aids in determining the appropriateness of anterior or posterior approaches and the necessity for fusion, considering the surgical level and K-line status. The complexity of surgical situations and diversity of treatment methods for DCM can be effectively managed using an algorithmic approach. Furthermore, surgical techniques that minimize the stages and address challenging conditions could enhance treatment outcomes in DCM.

An in Vivo, Three-Dimensional (3D), Functional Centers of Rotation of the Healthy Cervical Spine

OBJECTIVE

This study examined cervical center of rotation (COR) positions in 7 postures using validated cone beam computed tomography (CBCT) combined with 3D-3D registration in healthy volunteers.

METHODS

CBCT scans were performed on 20 healthy volunteers in 7 functional positions, constructing a three-dimensional (3D) model. Images were registered to the neutral position using 3D-3D registration, allowing analysis of kinematic differences and rotational axes. COR measurements were obtained for each segment (C2/3 to C6/7) in each posture.

RESULTS

The CORs of C2/3 to C6/7 were predominantly posterior (-5.3 ± 3.8 ∼ -0.6 ± 1.2 mm) and superior (16.5 ± 6.0 ∼ 23.6 ± 3.2 mm) to the intervertebral disc's geometric center (GC) in flexion and extension. However, the C4/5 segment's COR was anterior to the GC (2.0 ± 9.8 mm) during flexion and close to it in the right-left direction. During left-right twisting, the CORs of C2/3-C6/7 were posterior (-21.8 ± 10.5 ∼-0.9 ± 0.8 mm) and superior (3.1 ± 7.5 ∼23.2 ± 3.6 mm) to the GCs in anterior-posterior and superior-inferior directions, without consistent right-left directionality. During left-right bending, each segment's COR was predominantly posterior (-25.2 ± 13.1 ∼-6.5 ± 9.9 mm) and superior (0.3 ± 12.5 ∼12.1 ± 5.1 mm) to the GC in anterior-posterior and superior-inferior directions, except for the C2/3 segment, located inferiorly (-5.9 ± 4.1 mm) in left bending. The right-left COR position varied across segments.

CONCLUSIONS

Our findings reveal segment-specific and posture-dependent COR variations. Notably, the CORs of C3/4, C4/5, and C5/6 consistently align near the intervertebral disc's GC at different postures, supporting their suitability for total disc replacement surgery within the C3/4 to C5/6 segments.

Endoscopic Lumbar Disc Surgery Experience with the TESSYS Technique in 253 Case Series

Background: Herniated lumbar disc (HLD) is a widespread medical problem which can require surgery. Minimally invasive surgical management can represent an extremely valuable option for patients suffering from HLDs. Transforaminal endoscopic lumbar discectomy is an alternative to classical microdiscectomy which was proposed more than two decades ago and has evolved technologically with time. Methods: The transforaminal endoscopic spine system (TESSYS) technique has been introduced in recent years and offers the advantage of performing a controlled foraminal augmentation with full nerve root protection. We started using this technique in 2016 and prospectively evaluated the results of endoscopic TESSYS-based operations performed in a three-year period until the end of 2019. Selection criteria were very strict, and we included only patients with unilateral radicular pain with no instability who failed conservative therapy. Out of the 253 patients operated on in that time span, 183 were available for follow-up evaluation. Results: After surgery, there was a clinically significant improvement of all symptoms which basically lasted in the long-term follow-up. Complications were limited and generally minor. Redo surgery with microdiscectomy was required only in four cases. Obesity did not play a clear negative role in patients' outcome. Conclusions: Endoscopic transforaminal discectomy with the TESSYS technique represents a valuable management option for patients harbouring unilateral herniated lumbar disc located laterally.

Sagittal Balance Parameters and Proximal Junctional Kyphosis in Adolescent Idiopathic Scoliosis

Background: To review and evaluate multiple preoperative and postoperative sagittal parameters and their association with the risk of developing proximal junctional kyphosis (PJK) in patients with adolescent idiopathic scoliosis (AIS) who undergo correction surgery. Methods: A systematic search was performed in December 2022 in PubMed, Embase and the Cochrane Library to retrieve all the studies relevant to our research. After the study selection and data extraction following PRISMA guidelines, RevMan 5.3 was used for statistical analysis. All the analyzed factors were evaluated by using odds ratios and weighted mean differences with 95% confidence intervals. Moreover, the meta-analysis of proportions via MedCalc was used for analyzing quantitative data from the studies. Results: A total of 22 studies were included in our meta-analysis. All the available values of sagittal parameters were evaluated. Among all the potential risk factors, higher preoperative thoracic kyphosis (Test for overall effect Z = 11.79, p < 0.00001), higher preoperative sagittal vertical axis (SVA) (test for overall effect Z = 11.19, p < 0.00001), greater thoracic kyphosis change post-op. compared to pre-op. (test for overall effect Z = 6.02, p < 0.00001), increased postoperative lumbar lordosis (test for overall effect Z = 3.65, p = 0.0003), higher post-op. SVA (test for overall effect Z = 24.93, p < 0.00001) and a larger pelvic incidence/lumbar lordosis (PI/LL) mismatch (test for overall effect Z = 20.50, p < 0.00001) were found to be the risk factors for PJK after AIS surgery. Moreover, a decreased rod contour angle (RCA) (test for overall effect Z = 3.79, p < 0.0002) and higher proximal junctional angle-rod contour angle (PJA-RCA) (test for overall effect Z = 39.18, p < 0.00001) play a significant role in the risk of developing PJK after AIS correction. Conclusions: Sagittal balance is of great importance when considering the surgical correction of AIS. Many factors in our meta-analysis were found to increase the incidence for PJK such as higher preoperative thoracic kyphosis and pre-op. SVA. Furthermore, increased thoracic kyphosis change, increased post-operative lumbar lordosis, SVA and PI/LL mismatch are also factors that influence the possibility of post-op. PJK. Lastly, RCA and PJA-RCA are two important factors that need attention during AIS, as over-contouring of the rod could lead to PJK in AIS patients.

Exploring the mechanisms of kaempferol in neuroprotection: Implications for neurological disorders

Kaempferol, a flavonoid compound found in various fruits, vegetables, and medicinal plants, has garnered increasing attention due to its potential neuroprotective effects in neurological diseases. This research examines the existing literature concerning the involvement of kaempferol in neurological diseases, including stroke, Parkinson's disease, Alzheimer's disease, neuroblastoma/glioblastoma, spinal cord injury, neuropathic pain, and epilepsy. Numerous in vitro and in vivo investigations have illustrated that kaempferol possesses antioxidant, anti-inflammatory, and antiapoptotic properties, contributing to its neuroprotective effects. Kaempferol has been shown to modulate key signaling pathways involved in neurodegeneration and neuroinflammation, such as the PI3K/Akt, MAPK/ERK, and NF-κB pathways. Moreover, kaempferol exhibits potential therapeutic benefits by enhancing neuronal survival, attenuating oxidative stress, enhancing mitochondrial calcium channel activity, reducing neuroinflammation, promoting neurogenesis, and improving cognitive function. The evidence suggests that kaempferol holds promise as a natural compound for the prevention and treatment of neurological diseases. Further research is warranted to elucidate the underlying mechanisms of action, optimize dosage regimens, and evaluate the safety and efficacy of this intervention in human clinical trials, thereby contributing to the advancement of scientific knowledge in this field.

Biomechanical Comparison of Anterior Cervical Corpectomy Decompression and Fusion, Anterior Cervical Discectomy and Fusion, and Anterior Controllable Antedisplacement and Fusion in the Surgical Treatment of Multilevel Cervical Spondylotic Myelopathy: A Finite Element Analysis

PURPOSE

Multilevel cervical spondylotic myelopathy poses significant challenges in selecting optimal surgical approaches, warranting a comprehensive understanding of their biomechanical impacts. Given the lack of consensus regarding the most effective technique, this study aims to fill this critical knowledge gap by rigorously assessing and comparing the biomechanical properties of three distinct surgical interventions, including anterior controllable antedisplacement and fusion (ACAF), anterior cervical corpectomy decompression and fusion (ACCF), and anterior cervical discectomy and fusion (ACDF). The study offers pivotal insights to enhance treatment precision and patient outcomes.

METHODS

The construction of the cervical spine model involved a detailed process using CT data, specialized software (Mimics, Geomagic Studio, and Hypermesh) and material properties obtained from prior studies. Surgical instruments were modeled (titanium mesh, anterior cervical plate, interbody cage, and self-tapping screws) to simulate three surgical approaches: ACAF, ACCF, and ACDF, each with specific procedures replicating clinical protocols. A 75-N follower load with 2 Nm was applied to simulate biomechanical effects.

RESULTS

The range of motion decreased more after surgery for ACAF and ACDF than for ACCF, especially in flexion and lateral bending. ACCF have higher stress peaks in the fixation system than those of ACAF and ACDF, especially in flexion. The maximum von Mises stresses of the bone-screw interfaces at C3 of ACCF were higher than those of ACAF and ACDF. The maximum von Mises stresses of the bone-screw interfaces at C6 of ACDF were much higher than those of ACAF and ACCF. The maximum von Mises stresses of the grafts of ACCF and ACAF were much higher than those of ACDF. The maximum von Mises stresses of the endplate of ACCF were much higher than those of ACAF and ACDF.

CONCLUSION

The ACAF and ACDF models demonstrated superior cervical reconstruction stability over the ACCF model. ACAF exhibited lower risks of internal fixation failure and cage subsidence compared to ACCF, making it a promising approach. However, while ACAF revealed improved stability over ACCF, higher rates of subsidence and internal fixation failure persisted compared to ACDF, suggesting the need for further exploration of ACAF's long-term efficacy and potential improvements in clinical outcomes.