Degenerative Lumbar Spine Disease: Estimating Global Incidence and Worldwide Volume

Tetrahedral framework nucleic acids-based delivery of microRNA-155 alleviates intervertebral disc degeneration through targeting Bcl-2/Bax apoptosis pathway

Intervertebral disc degeneration (IDD) is one of the most common causes of chronic low back pain, which does great harm to patients' life quality. At present, the existing treatment options are mostly aimed at relieving symptoms, but the long-term efficacy is not ideal. Tetrahedral framework nucleic acids (tFNAs) are regarded as a type of nanomaterial with excellent biosafety and prominent performance in anti-apoptosis and anti-inflammation. MicroRNA155 is a non-coding RNA involved in various biological processes such as cell proliferation and apoptosis. In this study, a complex named TR155 was designed and synthesised with microRNA155 attached to the vertex of tFNAs, and its effects on the nucleus pulposus cells of intervertebral discs were evaluated both in vitro and in vivo. The experimental results showed that TR155 was able to alleviate the degeneration of intervertebral disc tissue and inhibit nucleus pulposus cell apoptosis via Bcl-2/Bax pathway, indicating its potential to be a promising option for the treatment of IDD.

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.

A randomized trial on three different minimally invasive decompression techniques for lumbar spinal stenosis. Five years follow-up from the NORDSTEN-SST

PURPOSE

The short-term clinical outcome for midline-preserving posterior decompression techniques was comparable. The aim of this study was to evaluate long-term clinical results after three different midline-preserving posterior decompression techniques.

MATERIAL

In the NORDSTEN spinal stenosis trial (NORDSTEN-SST) 437 patients were randomized to three different midline-retaining posterior decompression techniques: Unilateral laminotomy with crossover (UL), bilateral laminotomy (BL) and spinous process osteotomy (SPO). Primary outcome was the mean change in Oswestry disability index (ODI) score at five-years follow-up. Secondary outcomes were the proportion of patients classified as success, mean change in EQ-5D, ZCQ-score, NRS-score for leg and low back pain, a seven-point Global Perceived Effect (GPE) Scale and proportion of subsequential spinal surgery.

RESULTS

The number of patients that completed follow-up data after five years was 358 (82%): In the UL, BL and SPO group the numbers were 122, 119 and 117, respectively. Mean age at baseline was 66.7 (SD 8.2) years, mean BMI was 27.8 (SD 4.1), and 172/358 (48%) were female. In the UL group the mean change was  -18.2 (95% CI  -21.0  -5.4), in the BL group it was  -19.0 (95% CI -21.9-16.1) and in the SPO it was  -18.6 (95% CI  -21.6-15.7) (p = 0.917). No significant differences in the secondary outcomes between the three surgical groups were found, also the subsequent spinal surgery rates were similar.

CONCLUSION

There were no significant differences in patient reported outcomes and subsequent spinal surgery rates after the three different decompression techniques at five-year follow-up.

Perioperative management of antithrombotic therapy in elderly patients undergoing lumbar discectomy: a retrospective study on 163 patients

BACKGROUND CONTEXT

The prevalence of lumbar disc herniation (LDH) has risen alongside the aging population, often necessitating neurosurgical intervention. However, managing antithrombotic medications in elderly patients with a history of major cardiovascular events (MACE) presents challenges, as treatment may require modification or cessation. This study aims to compare surgical outcomes among elderly patients receiving antithrombotic drugs and assess their impact and potential complications. The findings aim to inform the management of elderly patients with cardiovascular and spinal conditions undergoing neurosurgery.

METHODS

This retrospective, observational study was conducted at a single center. A total of 163 patients aged 60 or above who underwent lumbar discectomy for LDH were included. Patients were categorized into three groups based on their antithrombotic drug management: Group A (46 patients) replaced antiplatelet agents with low-dose aspirin for secondary prevention, Group B (54 patients) discontinued antiplatelet agents for primary prevention one week preoperatively and replaced them with LMWH, and Group C (63 patients) did not receive antithrombotic medication. Intraoperative blood loss, surgical time, and postoperative hospitalization were analyzed across all three groups. Continuous variables were compared between groups using the two-tailed Mann-Whitney test, with significance set at p < 0.05.

RESULTS

No significant differences were found in intraoperative blood loss or surgical time among groups A, B, and C. Similarly, no significant differences were observed between groups B and C across all analyzed variables. No early or delayed hemorrhagic complications occurred perioperatively or during the 3-month postoperative follow-up period.

CONCLUSIONS

The study suggests that elective discectomy surgery in patients receiving anticoagulant and antiplatelet therapies may proceed without early complications and can be safely continued perioperatively. These findings have implications for the management of elderly patients requiring neurosurgical intervention in the context of cardiovascular comorbidities.

Convolutional Neural Network Incorporating Multiple Attention Mechanisms for MRI Classification of Lumbar Spinal Stenosis

BACKGROUND

Lumbar spinal stenosis (LSS) is a common cause of low back pain, especially in the elderly, and accurate diagnosis is critical for effective treatment. However, manual diagnosis using MRI images is time consuming and subjective, leading to a need for automated methods.

OBJECTIVE

This study aims to develop a convolutional neural network (CNN)-based deep learning model integrated with multiple attention mechanisms to improve the accuracy and robustness of LSS classification via MRI images.

METHODS

The proposed model is trained on a standardized MRI dataset sourced from multiple institutions, encompassing various lumbar degenerative conditions. During preprocessing, techniques such as image normalization and data augmentation are employed to enhance the model's performance. The network incorporates a Multi-Headed Self-Attention Module, a Slot Attention Module, and a Channel and Spatial Attention Module, each contributing to better feature extraction and classification.

RESULTS

The model achieved 95.2% classification accuracy, 94.7% precision, 94.3% recall, and 94.5% F1 score on the validation set. Ablation experiments confirmed the significant impact of the attention mechanisms in improving the model's classification capabilities.

CONCLUSION

The integration of multiple attention mechanisms enhances the model's ability to accurately classify LSS in MRI images, demonstrating its potential as a tool for automated diagnosis. This study paves the way for future research in applying attention mechanisms to the automated diagnosis of lumbar spinal stenosis and other complex spinal conditions.

Cellular and Molecular Mechanisms of Hypertrophy of Ligamentum Flavum

Hypertrophy of the ligamentum flavum (HLF) is a common contributor to lumbar spinal stenosis (LSS). Fibrosis is a core pathological factor of HLF resulting in degenerative LSS and associated low back pain. Although progress has been made in HLF research, the specific molecular mechanisms that promote HLF remain to be defined. The molecular factors involved in the onset of HLF include increases in inflammatory cytokines such as transforming growth factor (TGF)-β, matrix metalloproteinases, and pro-fibrotic growth factors. In this review, we discuss the current understanding of the mechanisms involved in HLF with a particular emphasis on aging and mechanical stress. We also discuss in detail how several pathomechanisms such as fibrosis, proliferation and apoptosis, macrophage infiltration, and autophagy, in addition to several molecular pathways involving TGF-β1, mitogen-activated protein kinase (MAPKs), and nuclear factor-κB (NF-κB) signaling, PI3K/AKT signaling, Wnt signaling, micro-RNAs, extracellular matrix proteins, reactive oxygen species (ROS), etc. are involved in fibrosis leading to HLF. We also present a summary of the current advancements in preclinical animal models for HLF research. In addition, we update the current and potential therapeutic targets/agents against HLF. An improved understanding of the molecular processes behind HLF and a novel animal model are key to developing effective LSS prevention and treatment strategies.

Human molecular mechanisms of discogenic low back pain: A scoping review

The limited understanding of the mechanisms underlying human discogenic low back pain (DLBP) has hampered the development of effective treatments. While there is much research on disc degeneration, the association between degeneration and pain is weak. Therefore, there is an urgent need to identify pain-inducing molecular mechanism to facilitate the development of mechanism-specific therapeutics. This scoping review aims to determine the current knowledge of molecular mechanisms associated with human DLBP. A systematic search on CENTRAL, CINAHL, Citation searching, ClinicalTrials.gov, Embase, Google Scholar, MEDLINE, PsycINFO, PubMed, Scopus, Web of Science, and World Health Organization was performed. Studies with human DLBP as diagnosed by discography or imaging that analyzed human disc tissues and reported pain-related outcomes were included, and those on predominant radicular pain were excluded. The search returned 6012 studies. Most studies did not collect pain-related outcomes. Those that included pain assessment relied on self-report of pain intensity and disability. Six studies qualified for data extraction and synthesis. The main molecular mechanisms associated with DLBP were the expressions of nociceptive neuropeptides and cytokines, particularly TNF-αdue to its strong association with pain outcomes. Activation of NF-κB signaling pathway, alterations in adrenoceptor expressions, and increase in reactive oxygen species (ROS) were also associated with DLBP through regulation of pro-inflammatory factors and pain-related neuropeptides. Current evidence converges to TNF-α, NF-κB signaling, and ROS-induced pro-inflammation. Major weaknesses in the current literature are the focus on degeneration without pain phenotyping, and lack of association of molecular findings with pain outcomes. PERSPECTIVE: This scoping review identified TNF-α, NF-κB signaling, and ROS-induced pro-inflammation as relevant mechanisms of human discogenic low back pain. Major weaknesses in the current literature are the focus on degeneration without pain phenotyping, and lack of association of molecular findings with pain outcomes.

Learning Curve of Endoscopic Lumbar Discectomy - A Systematic Review and Meta-Analysis of Individual Participant and Aggregated Data

STUDY DESIGN

A systematic review and meta-analysis of individual participant and aggregated data.

OBJECTIVES

To define the learning curves of endoscopic discectomies using unified statistical methodologies.

METHODS

Searches returned 913 records, with 118 full-text articles screened. Studies of endoscopic lumbar spine surgery reporting outcomes by case order were included. Mixed-effects nonlinear, logistic, and beta meta-regressions prdwere conducted to define the learning curves.

RESULTS

13 studies involving 864 patients among 15 surgeons were included in total. For transforaminal endoscopic discectomy, the estimated operating time for the first case was 95 min [CI: 87-104], and the estimated plateau was 66 minutes [CI: 51-81]. An estimated 21 cases [CI: 18-25] were required to overcome 80% of this deficit, but near-plateau performance was expected only after 59 cases [CI: 51-70]. The estimated risk of surgical complications on the first case was 25% [CI: 11%-46%], with an 80% reduction in relative risk requiring an estimated 41 cases. The expected postoperative VAS leg pain score after the first case was 2.7 [CI: 1.8-3.8], with an 80% improvement requiring an estimated 96 cases. Similar numbers were required to overcome the learning curves in interlaminar and biportal endoscopic discectomies.

CONCLUSIONS

Approximately 60 cases are required to achieve proficiency in endoscopic lumbar spine surgery, although the greatest part of the learning curve can be overcome with 20 cases. This should be considered when designing implementation programmes for surgeons and service providers that wish to incorporate endoscopic spinal surgery into their practice.

The Application of Deep Learning to Accurately Identify the Dimensions of Spinal Canal and Intervertebral Foramen as Evaluated by the IoU Index

Artificial intelligence has garnered significant attention in recent years as a rapidly advancing field of computer technology. With the continual advancement of computer hardware, deep learning has made breakthrough developments within the realm of artificial intelligence. Over the past few years, applying deep learning architecture in medicine and industrial anomaly inspection has significantly contributed to solving numerous challenges related to efficiency and accuracy. For excellent results in radiological, pathological, endoscopic, ultrasonic, and biochemical examinations, this paper utilizes deep learning combined with image processing to identify spinal canal and vertebral foramen dimensions. In existing research, technologies such as corrosion and expansion in magnetic resonance image (MRI) processing have also strengthened the accuracy of results. Indicators such as area and Intersection over Union (IoU) are also provided for assessment. Among them, the mean Average Precision (mAP) for identifying intervertebral foramen (IVF) and intervertebral disc (IVD) through YOLOv4 is 95.6%. Resnet50 mixing U-Net was employed to identify the spinal canal and intervertebral foramen and achieved IoU scores of 79.11% and 80.89%.

Comparison of midline lumbar interbody fusion and minimally invasive transforaminal lumbar interbody fusion for treatment of lumbar degeneration disease

Midline lumbar interbody fusion (MIDLIF) and minimally invasive transforaminal interbody fusion (MIS-TLIF) are two minimally invasive lumbar fusion methods that have gained popularity in the past two decades. MIDLIF involves the use of cortical bone trajectory screws, whereas MIS-TLIF uses traditional pedicle screws. However, there is a significant lack of research directly examining the clinical efficacy of these two methods in treating single-segment lumbar degenerative diseases. Hence, the objective of our retrospective study is to assess and contrast the surgical and clinical results of MIDLIF and MIS-TLIF. The study population comprised 133 patients diagnosed with single-segment lumbar degenerative disease that received treatment using either MIDLIF (n = 65) or MIS-TLIF (n = 68) in our department from January 2017 to January 2019. The fusion rates for MIDLIF were consistently lower than MID-TLIF at all post-operative time periods of follow-up, however, the differences between the two groups were not statistically significant. The 1-year fusion rates were 81.5% (MIDLIF) and 83.8% (MIS-TLIF) (P = 0.728), and the 2-year fusion rates were 87.7% (MIDLIF) and 91.2% (MIS-TLIF) (P = 0.513). The final follow-up fusion rates were 93.8% (MIDLIF) and 95.6% (MIS-TLIF) (P = 0.653). MIDLIF had several advantages over MIS-TLIF, including a shorter operative time (135.2 ± 15.70 vs. 160.1 ± 17.2 min, P < 0.001), decreased intraoperative blood loss (147.9 ± 36.4 vs. 169.5 ± 24.7 mL, P < 0.001), and a shorter length of hospital stay (10.8 ± 3.1 vs. 12.4 ± 4.1d; P = 0.014). No significant differences were seen between the groups in terms of the postoperative day of ambulation, Oswestry dysfunction index (ODI) scores, and visual analog scale (VAS) scores for leg and lower back pain (P > 0.05). Although not significant (P = 0.707), MIDLIF (13.8%) had fewer overall complications than MIS-TLIF (16.2%). Therefore, compared to MIS-TLIF, MIDLIF provides perioperative benefits while achieving the same outcomes as MIS-TLIF in terms of fusion rate, pain relief, functional improvement, and complication rate.

How to Prevent Nerve Root Injury in Uniportal Full Endoscopic Lumbar Fusion Surgery? Insights From a Cadaveric Anatomic Study With Simulation Surgery

STUDY DESIGN

The study included 2 fresh-frozen cadavers.

OBJECTIVE

To elucidate the positional relationship between surgical instruments and nerve roots during full endoscopic facet-sparing (FE fs-TLIF) and full endoscopic facet-resecting (FE fr-TLIF) transforaminal lumbar interbody fusion and propose safe instrumentation insertion procedures and recommend cage glider designs aimed at protecting nerve roots.

BACKGROUND

Endoscopic surgical techniques are increasingly used for minimally invasive lumbar fusion surgery, with FE fr-TLIF and FE fs-TLIF being common approaches. However, the risk of nerve root injury remains a significant concern during these procedures.

PATIENTS AND METHODS

Eight experienced endoscopic spine surgeons performed uniportal FE fr-TLIF and FE fs-TLIF on cadaveric lumbar spines, totaling 16 surgeries. Postoperation, soft tissues were removed to assess the positional relationship between the cage entry point and nerve roots. Distances between the cage entry point, traversing nerve root, and exiting nerve root were measured. Safe instrumentation design and insertion procedures were determined.

RESULTS

In FE fr-TLIF, the mean distance between the cage entry point and traversing nerve root was significantly shorter compared with FE fs-TLIF (3.30 ± 1.35 vs . 8.58 ± 2.47 mm, respectively; P < 0.0001). Conversely, the mean distance between the cage entry point and the exiting nerve root was significantly shorter in FE fs-TLIF compared with FE fr-TLIF (3.73 ± 1.97 vs . 6.90 ± 1.36 mm, respectively; P < 0.0001). For FE fr-TLIF, prioritizing the protection of the traversing root using a 2-bevel tip cage glider was crucial. In contrast, for FE fs-TLIF, a single-bevel tip cage glider placed in the caudal location was recommended.

CONCLUSION

This study elucidates the anatomic relationship between cage entry points and nerve roots in uniportal endoscopic lumbar fusion surgery. Protection strategies should prioritize the traversing root in FE fr-TLIF and the exiting root in FE fs-TLIF, with corresponding variations in surgical techniques.

LEVEL OF EVIDENCE

Level V.

Quercetin relieves compression-induced cell death and lumbar disc degeneration by stabilizing HIF1A protein

Background

Lumbar disc degeneration (LDD) is a prevalent condition characterized by the decreased viability and functional impairment of nucleus pulposus mesenchymal stem cells (NPMSCs). Shaoyao-Gancao decoction (SGD), a traditional Chinese medicine formula, has been used to treat LDD, but its active components and mechanisms are unclear.

Methods

An integrative network pharmacology and transcriptome analysis were conducted to identify bioactive compounds in SGD that could target LDD. NPMSCs were cultured under mechanical compression as a cellular model of LDD. A rat model of annulus fibrosus needle-puncture was established to induce intervertebral disc degeneration. The effects of quercetin, a predicted active component, on alleviating compression-induced NPMSC death and LDD were evaluated in vitro and in vivo.

Results

The analysis identified hypoxia-inducible factor 1-alpha (HIF1A) as a potential target of quercetin in LDD. HIF1A was upregulated in degenerated human disc samples and compression-treated NPMSCs. Quercetin treatment alleviated compression-induced oxidative stress, apoptosis, and loss of viability in NPMSCs by stabilizing HIF1A. The protective effects of quercetin were abrogated by HIF1A inhibition. In the rat model, quercetin ameliorated intervertebral disc degeneration.

Conclusion

Our study identified HIF1A as a protective factor against compression-induced cell death in NPMSCs. Quercetin, a bioactive compound found in the traditional Chinese medicine formula SGD, improved the survival of NPMSCs and alleviated LDD progression by stabilizing HIF1A. Targeting the HIF1A pathway through natural compounds like quercetin could represent a promising strategy for the clinical management of LDD and potentially other degenerative disc diseases.

Comparison of the short-term efficacy of MIS-TLIF and Endo-LIF for the treatment of two-segment lumbar degenerative disease

BACKGROUND

This study retrospectively compared short-term clinical outcomes and complications of minimally invasive surgery transforaminal lumbar interbody fusion(MIS-TLIF)and endoscopic lumbar interbody fusion(Endo-LIF))for two-segmental lumbar degenerative disease, aiming to guide spine surgeons in selecting surgical approaches.

METHODS

From January 2019 to December 2023, 30 patients were enrolled,15 in the MIS-TLIF group and 15 in the Endo-LIF group. All patients were followed up for more than 3 months after surgery and the following information was recorded: (1)surgery time, difference in hemoglobin between preoperative and postoperative, surgical costs, first time out of bed after operation, postoperative hospitalization time, postoperative complication; (2) ODI score (The Oswestry Disability Index), leg and back VAS score (Visual Analogue Scale), and lumbar vertebra JOA score (Japanese Orthopaedic Association Scores); (3) MacNab score at final follow-up to assess clinical outcome, CT to evaluate lumbar fusion.

RESULTS

There were significant differences between the two groups regarding operation time and cost, with the MIS-TLIF group performing significantly better. Intraoperative bleeding was considerably less in the Endo-LIF group compared to the MIS-TLIF group. However, there were no significant differences in the time of the first postoperative ambulation, postoperative hospitalization time, and postoperative complications. There was no significant difference in preoperative VAS, ODI, and JOA between the two surgical groups There were no significant differences in VAS(leg), ODI, and JOA scores between the two groups before and at 1 day,7 days, 1 month, 3 months and final follow-up. However, at 1 day postoperatively, the VAS( back)score in the Endo-LIF group was lower than that in the MIS-TLIF group, and the difference was statistically significant. At the final follow-up, all patients achieved grade III and above according to the Bridwell criteria, and there was no significant difference between the two surgical groups compared to each other. According to the MacNab score at the final follow-up, the excellent rate was 80.00% in the Endo-LIF group and 73.33% in the MIS-TLIF group, with no significant difference between the two groups.

CONCLUSION

There was no significant difference in short-term efficacy and safety between Endo-LIF and MIS-TLIF for two-segment degenerative lumbar diseases. MIS-TLIF has a shorter operative time and lower costs, while Endo-LIF causes less tissue damage, blood loss, and early postoperative pain, aiding long-term recovery. Both MIS-TLIF and Endo-LIF are promising for treating two-segment lumbar degenerative disease. The choice of a surgical procedure depends on the patient's financial situation, their ability to tolerate surgery, and the surgeon's expertise.

Impact of Preoperative Intervertebral Disc Degeneration on Patient-Reported Outcome Measures After Lumbar Fusion

OBJECTIVE

The Pfirrmann scoring system classifies lumbosacral disc degeneration based on magnetic resonance imaging signal intensity. The relationship between pre-existing disc degeneration and patient-reported outcome measures (PROMs) after one-level lumbar fusion is not well documented. The purpose of this study was to investigate the relationship between the severity of preoperative intervertebral disc degeneration and preoperative and postoperative PROMs in patients undergoing one-level lumbar fusion.

METHODS

All adult patients who underwent posterior lumbar decompression and fusion or transforaminal lumbar interbody fusion between 2014 and 2022 were included. Patient demographics and comorbidities were extracted from medical records. Lumbar intervertebral discs on sagittal magnetic resonance imaging T2-weighted images were assessed by 2 independent graders utilizing Pfirrmann criteria. Grades I-III were categorized as low-grade disc degeneration, while IV-V were considered high grade. Multivariable linear regression assessed the impact of disc degeneration on PROMs.

RESULTS

A total of 150 patients were included, of which 69 (46%) had low-grade disc degeneration, while 81 (54%) had high-grade degeneration. Patients with high-grade degeneration had increased preoperative visual analog scale (VAS)-Leg scores (6.10 vs. 4.54, P = 0.005) and displayed greater 1-year postoperative improvements in VAS-Back scores (-2.11 vs. -0.66, P = 0.002). Multivariable regression demonstrated Pfirrmann scores as independent predictors for both preoperative VAS-Leg scores (P = 0.004) and postoperative VAS-Back improvement (P = 0.005).

CONCLUSIONS

In patients undergoing one-level lumbar fusion, higher Pfirmann scores were associated with increased preoperative leg pain and greater 1-year postoperative improvement in back pain. Further studies into the relationship of preoperative disc degeneration and their impact on postoperative outcomes may help guide clinical decision-making and patient expectations.

The Effect of Patient Resilience on Postoperative Scores After One- and Two-Level Anterior Cervical Discectomy and Fusion

OBJECTIVE

To investigate the association between resilience and outcomes of pain and neck-related disability after single- and double-level anterior cervical discectomy and fusion (ACDF).

METHODS

Patients who underwent single- or double-level ACDF were sent a survey between 6 months and 2 years after surgery. The survey included the Brief Resilience Scale (BRS), visual analogue scale (VAS) for pain, Neck Disability Index (NDI), and Pain Self-Efficacy Questionnaire (PSEQ-2). Patients completed the VAS and NDI twice, once describing preoperative pain and disability and once describing current pain and disability. Respondents were classified as high resilience (HR), medium resilience (MR), or low resilience (LR). Demographics, PSEQ-2 scores, pre- and postoperative VAS and NDI scores, and change in VAS (ΔVAS) and NDI (ΔNDI) scores were compared between groups.

RESULTS

Thirty-three patients comprised the HR group, 273 patients comprised the MR group, and 47 patients comprised the LR group. All groups demonstrated postoperative improvement in VAS and NDI scores that exceeded previously established MCID values. The HR group demonstrated greater improvement in pain compared with the LR group (ΔVAS: -5.8 for HR vs. -4.4 for LR, P = 0.05). Compared with the MR group, the LR group demonstrated greater postoperative pain (VAS: 3.2 for LR vs. 2.5 for MR, P = 0.02) and disability (NDI: 11.9 for LR vs. 8.6 for MR, P = 0.02).

CONCLUSIONS

Patients demonstrated improvement in pain and neck-related disability after single- and double-level ACDF, regardless of resilience score. Patients with greater resilience may be expected to demonstrate more improvement in pain after ACDF.

Risk factors of revision operation and early revision for adjacent segment degeneration after lumbar fusion surgery: a case-control study

BACKGROUND CONTEXT

Adjacent segment degeneration (ASD) following lumbar fusion operation is common and can occur at varying timepoints after index surgery. An early revision operation for ASD, however, signifies a short symptom-free period and might increase the risk of successive surgeries.

PURPOSE

We aimed to elucidate the overall risk factors associated with revision surgeries for ASD with distinct attention to early revisions.

STUDY DESIGN/SETTING

Retrospective, case-control study.

PATIENT SAMPLE

The study included 86 patients who underwent revision operations for ASD after lumbar fusion in the revision group and 166 patients who did not for at least 5 years after index surgery.

OUTCOME MEASURES

Sagittal parameters, Pfirrmann grading, facet degeneration grading, and disc space height (DSH) of adjacent segments were assessed.

METHODS

Revision operations within 5 years postsurgery were defined as early revision. We compared the revision and no-revision groups as well as the early- and late-revision groups.

RESULTS

The revision group demonstrated a significantly greater preoperative C7-S1 sagittal vertical axis (SVA) (p=.001), postoperative C7-S1 SVA (p<.001), and postoperative pelvic incidence (PI)-lumbar lordosis (LL) (p<.001) than those in the no-revision group. Preoperative DSH of the proximal adjunct segment (p=.001), postoperative PI-LL (p=.014), and postoperative C7-S1 SVA (p=.037) exhibited significant association with ASD in logistic regression analysis. The early-revision group had a significantly higher patient age (p=.001) and a greater number of levels fused (p=.030) than those in the late-revision group. Multivariate Cox regression analysis demonstrated that old age (p=.045), a significant number of levels fused (p=.047), and a narrow preoperative DSH of the proximal adjacent level (p=.011) were risk factors for early revision.

CONCLUSIONS

Postoperative sagittal imbalance, including significant PI-LL and C7-S1 SVA were risk factors for revision operation for ASD but not for early revision. These factors are likely to affect the long-term risk of revision operation due to ASD and thus are not considered risk factors for early revision. Narrow DSH of the proximal adjacent level increased the risks of both revision and early revision surgeries. Moreover, old age and a significant number of levels fused further increased the risk for early revision for ASD.

Impact of sarcopenia on outcomes following lumbar spine surgery for degenerative disease: an updated systematic review and meta-analysis

PURPOSE

This study aimed to consolidate the evidence regarding the prognostic influence of sarcopenia in degenerative lumbar spine surgeries.

METHODS

A literature search of public databases was conducted up to Nov 15, 2023 using combinations of the key words "sarcopenia" and "lumbar spine surgery". Eligible studies were those that focused on adults undergoing decompression or fusion surgery for degenerative lumbar spine diseases, and compared the outcomes between patients with and without preoperative sarcopenia. Primary outcomes were change in ODI and back and leg pain VAS pain scores. Secondary outcomes were changes in Eq. 5D, JOA, SFHS-p scores, and LOS.

RESULTS

Ultimately, nine retrospective studies with a total of 993 patients were included. Sarcopenic patients exhibited significantly worse functional improvement as assessed by ODI compared to non-sarcopenic patients (pooled standardized mean difference [pSMD] = 0.53, 95% confidence interval [CI]: 0.17-0.90). Back pain (pSMD = 0.31, 95% CI:0.15-0.47) and leg pain (pSMD = 0.21, 95% CI:0.02 - 0.39) improvement were also less in sarcopenic patients. Non-sarcopenic patients had greater improvements in Eq. 5D (pSMD = 0.25) and SFHS-p (pSMD = 0.39), and shorter LOS (pSMD = 0.62).

CONCLUSIONS

As compared to patients without sarcopenia, those with sarcopenia undergoing lumbar spine surgery for degenerative diseases have lower improvements in functional ability, quality of life, physical health, pain relief and extended hospitalization compared to those without sarcopenia.

Proteomic analysis of serum in a population-based cohort did not reveal a biomarker for Modic changes

Introduction

Modic changes (MC) are bone marrow lesions of vertebral bones, which can be detected with magnetic resonance imaging (MRI) adjacent to degenerated intervertebral discs. Defined by their appearance on T1 and T2 weighted images, there are three interconvertible types: MC1, MC2, and MC3. The inter-observer variability of the MRI diagnosis is high, therefore a diagnostic serum biomarker complementing the MRI to facilitate diagnosis and follow-up would be of great value.

Methods

We used a highly sensitive and reproducible proteomics approach: DIA/SWATH-MS to find serum biomarkers in a subset of the Northern Finland Birth Cohort 1966. Separately, we measured a panel of factors involved in inflammation and angiogenesis to confirm some potential biomarkers published before with an ELISA-based method called V-Plex.

Results

We found neither an association between the serum concentrations of the proteins detected with DIA/SWATH-MS with the presence of MC, nor a correlation with the size of the MC lesions. We did not find any association between the factors measured with the V-Plex and the presence of MC or their size.

Conclusion

Altogether, our study suggests that a robust and generally usable biomarker to facilitate the diagnosis of MC cannot readily be found in serum.

Comparison of Fusion Rate and Clinical Outcomes in Minimally Invasive and Conventional Posterior Fusion for Lumbar Degenerative Disease: A Network Meta-Analysis

BACKGROUND

The fusion rate, clinical efficacy, and complications of minimally invasive fusion surgery and open fusion surgery in the treatment of lumbar degenerative disease are still unclear.

METHODS

We conducted a literature search using PubMed, Embase, Cochrane Library, CNKI, and WANFANG databases.

RESULTS

This study included 38 retrospective studies involving 3097 patients. Five intervention modalities were considered: unilateral biportal endoscopic-lumbar interbody fusion (UBE-LIF), percutaneous endoscopic-lumbar interbody fusion (PE-LIF), minimally invasive-transforaminal lumbar interbody fusion (MIS-TLIF), transforaminal lumbar interbody fusion (TLIF), and posterior lumbar interbody fusion (PLIF). Quality assessment indicated that each study met acceptable quality standards. PE-LIF demonstrated reduced low back pain (Odds Ratio = 0.50, Confidence Interval: 0.38-0.65) and lower complication rate (Odds Ratio = 0.46, Confidence Interval: 0.25-0.87) compared to PLIF. However, in indirect comparisons, PE-LIF showed the lowest fusion rates, with the ranking as follows: UBE-LIF (83.2%) > MIS-TLIF (59.6%) > TLIF (44.3%) > PLIF (39.8%) > PE-LIF (23.1%). With respect to low back pain relief, PE-LIF yielded the best results, with the order of relief as follows: PE-LIF (96.4%) > MIS-TLIF (64.8%) > UBE-LIF (62.6%) > TLIF (23.0%) > PLIF (3.2%). Global and local consistency tests showed satisfactory results, and heterogeneity tests indicated good stability.

CONCLUSIONS

Compared to conventional open surgery, minimally invasive fusion surgery offered better scores for low back pain and Oswestry Disability Index, lower complication rates, reduced bleeding, and shorter hospital stays. However, minimally invasive fusion surgery did not show a significant advantage in terms of fusion rate and had a longer operative time.

The Decline of Lumbar Artificial Disc Replacement

Lower back pain associated with degenerative disc disease is a common occurrence, with many surgical treatments targeting the degenerated disc to relieve symptoms. Current surgical options for degenerative disc disease primarily consist of a discectomy followed by either spinal fusion or artificial disc replacement, with the former being increasingly more common in the lumbar region despite the risk of adjacent segment disease. Though artificial disc replacement aims to provide an increase in range of motion and decreases risk of adjacent segment disease, surgeons are increasingly opting for spinal fusion in the lumbar region. This review investigates underlying factors that may be contributing to this trend by assessing lumbar artificial disc replacement selection criteria, clinical outcomes, surgical technique, complications, revision burden, and overall cost. While these factors had some role in the physician's decision, ultimately the narrow selection criteria and lack of cost reimbursement by insurance has primarily led to the decline in lumbar artificial disc replacement.

Validation of a surgical simulator and establishment of quantitative performance thresholds-RealSpine simulation system for open lumbar decompressions

BACKGROUND CONTEXT

The majority of surgical training is conducted in real-world operations. High-fidelity surgical simulators may provide a safer environment for surgical training. However, the extent that it reflects real-world operations and surgical ability is often poorly characterized.

PURPOSE

(1) Assess the validity and fidelity of a surgical simulator; (2) Examine the quantitative relationship between simulation performance and markers of real-world ability; (3) Establish thresholds for surgical expertise, and estimate their external validity and accuracy.

STUDY DESIGN/SETTING

A cohort study of surgeons at a British neurosurgical center.

STUDY SAMPLE

Ten early-career "novice" surgeons and 8 board-certified "expert" neurosurgeons.

OUTCOMES MEASURES

(1) Face and content validity, and visual and haptic fidelity; (2) Construct validity; (3) Predictive and discriminative utility of quantitative performance thresholds.

METHODS

Participants performed unilateral lumbar decompressions on high-fidelity spinal simulators that replicate the bony and soft tissue anatomy along with physiological processes such as bleeding and CSF leaks. Operating times, measured from first surgical action to either self-perceived satisfactory decompression or the end of allocated time, were recorded. The performance was also assessed independently by 2 blinded spinal subspecialist neurosurgeons using OSATS, a validated surgical assessment tool that utilizes 5-point scales on a variety of technical domains to grade the overall technical proficiency. Validity and fidelity were assessed by expert neurosurgeons using quantitative questionnaires. Construct validity was assessed by ordinal regression of simulation performance against real-world surgical grade and portfolio. Thresholds of expert status by simulation performance was established, and their predictive and discriminative utility assessed by crossvalidation accuracy and AUC-ROC.

RESULTS

Operating time and expert assessments of simulation performance (OSATS) were strong and significant prdictors of surrogate markers of real-world surgical ability. The thresholds for expert status were operating time of 15 minutes and modified OSATS score of 15/20. These thresholds predicted expert status with 84.2% and 71.4% accuracy respectively. Strong discriminative ability was demonstrated by AUC-ROC of 0.95 and 0.83 respectively. All expert surgeons agreed that RealSpine simulators demonstrate high face validity, and high visual and haptic fidelity, with overall scores showing statistically significant agreement on these items (all scores at least 4/5, p<.0001). There was less consensus on content validity, but with still significant overall agreement (average score: 3.75/5, p=.023).

CONCLUSIONS

Real-world surgical ability and experience can be accurately predicted by defining objective quantitative thresholds on high-fidelity simulations. The thresholds established here, along with other data presented in this paper, may inform objectives and standards to be established in a spinal surgical training curriculum.

Single-cell RNA sequencing reveals the CRTAC1+ population actively contributes to the pathogenesis of spinal ligament degeneration by SPP1+ macrophage

Degenerative spinal stenosis is a chronic disease that affects the spinal ligaments and associated bones, resulting in back pain and disorders of the limbs among the elderly population. There are few preventive strategies for such ligament degeneration. We here aimed to establish a comprehensive transcriptomic atlas of ligament tissues to identify high-priority targets for pharmaceutical treatment of ligament degeneration. Here, single-cell RNA sequencing was performed on six degenerative ligaments and three traumatic ligaments to understand tissue heterogeneity. After stringent quality control, high-quality data were obtained from 32,014 cells. Distinct cell clusters comprising stromal and immune cells were identified in ligament tissues. Among them, we noted that collagen degradation associated with CTHRC1+ fibroblast-like cells and calcification linked to CRTAC1+ chondrocyte-like cells were key features of ligament degeneration. SCENIC analysis and further experiments identified ATF3 as a key transcription factor regulating the pathogenesis of CRTAC1+ chondrocyte-like cells. Typically, immune cells infiltrate localized organs, causing tissue damage. In our study, myeloid cells were found to be inflammatory-activated, and SPP1+ macrophages were notably enriched in degenerative ligaments. Further exploration via CellChat analysis demonstrated a robust interaction between SPP1+ macrophages and CRTAC1+ chondrocyte-like cells. Activated by SPP1, ATF3 propels the CRTAC1/MGP/CLU axis, fostering ligament calcification. Our unique resource provides novel insights into possible mechanisms underlying ligament degeneration, the target cell types, and molecules that are expected to mitigate degenerative spinal ligament. We also highlight the role of immune regulation in ligament degeneration and calcification, enhancing our understanding of this disease.

Endoscopic Treatment of Lumbar Degenerative Disc Disease: A Narrative Review of Full-Endoscopic and Unilateral Biportal Endoscopic Spine Surgery

BACKGROUND

Degenerative lumbar spine disease is the leading cause of disability and work absenteeism worldwide. Lumbar microdiscectomy became the standard treatment for herniated discs and stenotic disease. With the evolution of different techniques, endoscopic spinal surgery emerged to minimize the surgical footprint while providing at least non-inferior results. Currently, two different types of endoscopic spine procedures are dominating the surgical scenario: "Full-Endoscopic" (FE) and Unilateral Biportal Endoscopic" (UBE) Spine Surgery. The aim of this study is to describe and analyze their indications, their technical characteristicswithitsadvantagesanddisadvantagesofbothtechniquesandtheirfuture trends.

METHODS

We performed a narrative review of the most relevant articles published up to August 2023 through a Pub Med search. The search terms " FE Spine Surgery" and " UBE Spine Surgery" were used. The articles selected, were independently reviewed by 3 authors and 55 full text articles were reviewed.

RESULTS

The FE and UBE Spine Surgery techniques were described. The FE technique is performed with a monoportal access under constant saline irrigation. The FE comprises the transforaminal and the interlaminar approaches, and the indication depends from the pathology to treat, and still remains controversial. UBE can approach also the spine from a posterior, postero lateral,and para spinal route. It uses two different ports addressed to a target with continuous irrigation. The process of establishing these two portals is called triangulation.

CONCLUSIONS

FE and UBE spine surgery have demonstrated outcomes comparable to open surgery, minimizing complications and surgical footprint.

How do information and physiotherapy affect health-related quality of life among patients with spinal stenosis undergoing decompression surgery: A qualitative study

BACKGROUND

There is a lack of qualitative research on how patients with lumbar spinal stenosis (LSS) undergoing surgery perceive their health-related quality of life (HRQOL). Research that increases our understanding in this area could facilitate a biopsychosocial approach to care.

AIM

We aimed to investigate the experiences of patients with LSS undergoing decompression surgery regarding their pre- and post-surgery perceptions of HRQOL and the pre-and post-operative information and physiotherapy.

METHOD

We used a qualitative design with semi-structured interviews to perform content analysis using an inductive approach. Twelve patients (7 female, 5 male) were included post-surgery and interviewed by phone. The interviews were recorded and transcribed verbatim.

RESULTS

Four distinct categories with nine associated subcategories were identified: Patients' feelings of safety and empowerment are enhanced by healthcare professionals; Divided perceptions of information and physiotherapy in a group context; Health-related quality of life is associated with patients' perceived physical capacity; Patients' optimism and concerns influence health-related quality of life.

CONCLUSION

Both physical and psychological factors pre- and post-surgery appear to influence patients' HRQOL. Inherent optimism and feelings of empowerment in the care process appear to be important factors, regardless of physical health status. A strong patient-provider relationship is important to promote self-efficacy, which may positively affect perceived HRQOL and is in line with the generally recommended biopsychosocial approach in the treatment of people with low back pain. As qualitative studies in this area are scarce, there is a need for further studies to validate our findings.

The Effect of Graded Activity and Pain Education After Lumbar Spinal Fusion on Sedentary Behavior 3 and 12 Months Postsurgery: A Randomized Controlled Trial

OBJECTIVES

To examine the effect of an early postsurgical intervention consisting of graded activity and pain education (GAPE) in patients with chronic low back pain (CLBP) undergoing lumbar spinal fusion (LSF) on sedentary behavior, disability, pain, fear of movement, self-efficacy for exercise and health-related quality of life (HRQoL) at 3-, 6-, and 12 months follow-up.

DESIGN

A parallel-group, observer-blinded randomized controlled trial.

SETTING

Department of Occupational- and Physiotherapy and the Centre for Rheumatology and Spine Diseases, Rigshospitalet, Denmark.

PARTICIPANTS

In total, 144 participants undergoing an LSF for CLBP were randomly assigned to an intervention or a control group.

INTERVENTIONS

The intervention group received 9 sessions of GAPE, based on principles of operant conditioning.

MAIN OUTCOME MEASURES

The primary outcome was reduction in time spent in sedentary behavior, measured by an accelerometer at 3 months. The secondary outcomes were reduction in time spent in sedentary behavior at 12 months and changes from baseline to 3-, 6-, and 12 months on disability, pain, fear of movement, self-efficacy for exercise, and HRQoL.

RESULTS

No difference in changes in sedentary behavior between groups was found 3 months after surgery. At 12 months after surgery, there was a significant difference between groups (mean difference: -25.4 min/d (95% confidence interval -49.1 to -1.7)) in favor of the intervention group.

CONCLUSIONS

Compared with usual care, GAPE had no effect on short-term changes in sedentary behavior but GAPE had a statistical, but possibly not clinical significant effect on sedentary behavior 12 months after LSF. Further, the behavioral intervention was safe to perform.

Effect of Acupuncture on Neurogenic Claudication Among Patients With Degenerative Lumbar Spinal Stenosis : A Randomized Clinical Trial

BACKGROUND

Acupuncture may improve degenerative lumbar spinal stenosis (DLSS), but evidence is insufficient.

OBJECTIVE

To investigate the effect of acupuncture for DLSS.

DESIGN

Multicenter randomized clinical trial. (ClinicalTrials.gov: NCT03784729).

SETTING

5 hospitals in China.

PARTICIPANTS

Patients with DLSS and predominantly neurogenic claudication pain symptoms.

INTERVENTION

18 sessions of acupuncture or sham acupuncture (SA) over 6 weeks, with 24-week follow-up after treatment.

MEASUREMENTS

The primary outcome was change from baseline in the modified Roland-Morris Disability Questionnaire ([RMDQ] score range, 0 to 24; minimal clinically important difference [MCID], 2 to 3). Secondary outcomes were the proportion of participants achieving minimal (30% reduction from baseline) and substantial (50% reduction from baseline) clinically meaningful improvement per the modified RMDQ.

RESULTS

A total of 196 participants (98 in each group) were enrolled. The mean modified RMDQ score was 12.6 (95% CI, 11.8 to 13.4) in the acupuncture group and 12.7 (CI, 12.0 to 13.3) in the SA group at baseline, and decreased to 8.1 (CI, 7.1 to 9.1) and 9.5 (CI, 8.6 to 10.4) at 6 weeks, with an adjusted difference in mean change of -1.3 (CI, -2.6 to -0.03; P = 0.044), indicating a 43.3% greater improvement compared with SA. The between-group difference in the proportion of participants achieving minimal and substantial clinically meaningful improvement was 16.0% (CI, 1.6% to 30.4%) and 12.6% (CI, -1.0% to 26.2%) at 6 weeks. Three cases of treatment-related adverse events were reported in the acupuncture group, and 3 were reported in the SA group. All events were mild and transient.

LIMITATION

The SA could produce physiologic effects.

CONCLUSION

Acupuncture may relieve pain-specific disability among patients with DLSS and predominantly neurogenic claudication pain symptoms, although the difference with SA did not reach MCID. The effects may last 24 weeks after 6-week treatment.

PRIMARY FUNDING SOURCE

2019 National Administration of Traditional Chinese Medicine "Project of building evidence-based practice capacity for TCM-Project BEBPC-TCM" (NO. 2019XZZX-ZJ).

Efficacy and safety of percutaneous cement discoplasty in the management of degenerative spinal diseases: A systematic review and meta-analysis

BACKGROUND

Percutaneous cement discoplasty (PCD) is a minimally invasive procedure. We aim to explore the efficacy and indication(s) of PCD in patients with degenerative disc disease (DDD).

METHODS

The search was conducted across Ovid MEDLINE, Ovid Embase, and PubMed. Data on study design, patient demographics, pre- and post-procedure Visual Analog Scale (VAS) and Oswestry Disability Index (ODI) scores, and complications were extracted. Inclusion criteria focused on adult patients with degenerative spinal diseases treated with cement discoplasty. The overall effect size was evaluated using a forest plot, and heterogeneity was assessed using the I2 statistic and chi-squared test.

RESULTS

The search strategy yielded six studies, which included 336 patients (73.8% female, 26.2% male) with a mean average age of 74.6 years. VAS scores were reported in all studies, showing a significant difference between pre- and post-PCD pain scores (Weighted Mean Difference [WMD]: -3.45; 95% CI: -3.83, -3.08; I2 = 15%; P < .001). ODI scores were reported in 83% of studies, with a significant difference between pre- and post-PCD scores (WMD: -22.22; 95% CI: -25.54, -18.89; I2 = 61%; p < .001). Complications reported included infections, thrombophlebitis, vertebral fractures, disc extrusion, and the need for further operations.

CONCLUSIONS

The analysis showed clinically significant improvements in pain and functional disability based on VAS and ODI scores. However, due to methodological limitations and a high risk of bias, the validity and generalizability of the findings are uncertain. Despite these issues, the results provide preliminary insights into PCD's potential efficacy and can guide future research to address current limitations.

The relation of osteoporotic vertebral fractures and spine degeneration on the occurrence of complications: a systematic review

STUDY DESIGN

Systematic review.

PURPOSE

Osteoporotic vertebral fractures (OVFs) and degenerative spine conditions are age-related and associated with higher morbidity and mortality and greater health care costs. The relationship between OVFs and prevalent spine degeneration is rarely reported. The aim of this study was to systematically review current literature on the influence of preexisting degenerative spine conditions in patients with OVFs on the occurrence of complications during and after treatment.

METHODS

A systematic literature review adhering to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines was performed using Web of Science and MEDLINE. We considered English and German articles published from January 1990 to December 2022. The inclusion criteria were patients with OVFs and preexisting spinal degeneration with complications such as subsequent fractures, deformity, implant failure and surgical and general complications. The included studies were controlled trials, cohort studies, and case series.

RESULTS

Ten articles met the inclusion criteria (two prospective studies, seven retrospective studies and one case series). These were divided into two groups: studies on OVFs in patients with coexisting degenerative spine conditions (n = 5) and studies on OVFs following surgical treatment for degenerative spine conditions (n = 5). Three studies reported more complications in patients with OVFs and severe degeneration. One study stated the opposite. One study did not find any correlation. The remaining studies described complications narratively. Subsequent fractures were the most frequent complications.

CONCLUSION

OVFs in patients with preexisting spinal degeneration seem to cause more complications. In addition to subsequent fractures, other complications have rarely been examined. The presence of degenerative changes or undergoing surgical correction may increase the risk of subsequent fractures.

Understanding the role of surgical intervention for patients with concomitant degenerative spinal disease without deformity and Parkinson's disease: a meta-analysis

INTRODUCTION

Parkinson's disease is a common neurodegenerative disease. With an aging population, co-existent degenerative diseases of the spine in these patients will become more prevalent.

RESEARCH QUESTION

This systematic review and meta-analysis aims to establish the incidence and risk of adverse outcomes following spinal surgery in patients with Parkinson's disease. Material and Methods A literature review was carried out in order to identify studies assessing the outcomes of adult patients with Parkinson's disease undergoing spinal surgery for degenerative conditions. Studies with less than ten subjects or those assessing surgery for spinal deformity or trauma were excluded.

RESULTS

Of 74 studies identified, seven were included for meta-analysis. In the 689,578 participants, there was a significantly higher incidence, but not higher risk, of complications (0.54 95% CI [0.19-0.85] vs 0.07 95% CI [0.01-0.41]; p = 0.048) and revision surgery (0.6 95% CI [0.25-0.88] vs 0.1 95% CI [0.05-0.19]; p = 0.003) amongst patients with Parkinson's disease compared to controls. We also demonstrated a significantly lower incidence but not lower risk of clinical improvement (0.27 95% CI [0.16-0.41] vs 0.57 95% CI [0.36-0.76]; p = 0.02) after surgery in patients with Parkinson's disease. There was no difference in the incidence or risk of death following surgery.

DISCUSSION AND CONCLUSION

Spinal surgery for concomitant degenerative diseases in patients with Parkinson's disease is associated with a lower incidence of clinical improvement and a higher incidence of complications. Medical management should be optimised before an individually tailored and well-considered surgical intervention is implemented.

Cyclic testing of standalone ALIF versus TLIF in lumbosacral spines of low bone mineral density: an ex vivo biomechanical study

PURPOSE

Screwed anterior lumbar interbody fusion (SALIF) alleviates the need for supplemental posterior fixation leading to reduction of perioperative morbidity. Specifically, elderly and multimorbid patients would benefit from shorter operative time and faster recovery but tend to have low bone mineral density (BMD). The current study aimed to compare loosening, defined as increase of ROM and NZ, of SALIF versus transforaminal lumbar interbody fusion (TLIF) under cyclic loading in cadaveric spines with reduced BMD.

METHODS

Twelve human spines (L4-S2; 6 male 6 female donors; age 70.6 ± 19.6; trabecular BMD of L5 84.2 ± 24.4 mgHA/cm3, range 51-119 mgHA/cm3) were assigned to two groups. SALIF or TLIF were instrumented at L5/S1. Range of motion (ROM) and neutral zone (NZ) were assessed before and after axial cyclic loading (0-1150 N, 2000 cycles, 0.5 Hz) in flexion-extension (Flex-Ext), lateral bending, (LB), axial rotation (AR).

RESULTS

ROM of the SALIF specimens increased significantly in all loading directions (p ≤ 0.041), except for left AR (p = 0.053), whereas for TLIF it increased significantly in left LB (p = 0.033) and Flex (p = 0.015). NZ of SALIF showed increase in Flex-Ext and LB, whereas NZ of TLIF did not increase significantly in any motion direction.

CONCLUSIONS

Axial compression loading caused loosening of SALIF in Flex-Ext and LB, but not TLIF at L5/S1 in low BMD specimens. Nevertheless, Post-cyclic ROM and NZ of SALIF is comparable to TLIF. This suggests that, neither construct is optimal for the use in patients with reduced BMD.

What is the early fate of adjacent segmental lordosis compensation at L3-4 and L5-S1 following a lateral versus transforaminal lumbar Interbody Fusion at L4-5?

INTRODUCTION

Degenerative spondylolisthesis causes translational and angular malalignment, resulting in a loss of segmental lordosis. This leads to compensatory adjustments in adjacent levels to maintain balance. Lateral lumbar interbody fusion (LLIF) and transforaminal lumbar interbody fusion (TLIF) are common techniques at L4-5. This study compares compensatory changes at adjacent L3-4 and L5-S1 levels six months post LLIF versus TLIF for grade 1 degenerative spondylolisthesis at L4-5.

METHODS

A retrospective study included patients undergoing L4-5 LLIF or TLIF with posterior pedicle screw instrumentation (no posterior osteotomy) for grade 1 spondylolisthesis. Pre-op and 6-month post-op radiographs measured segmental lordosis (L3-L4, L4-L5, L5-S1), lumbar lordosis (LL), and pelvic incidence (PI), along with PI-LL mismatch. Multiple regressions were used for hypothesis testing.

RESULTS

113 patients (61 LLIF, 52 TLIF) were studied. TLIF showed less change in L4-5 lordosis (mean = 1.04°, SD = 4.34) compared to LLIF (mean = 4.99°, SD = 5.53) (p = 0.003). L4-5 angle changes didn't correlate with L3-4 changes, and no disparity between LLIF and TLIF was found (all p > 0.16). In LLIF, greater L4-5 lordosis change predicted reduced compensatory L5-S1 lordosis (p = 0.04), while no significant relationship was observed in TLIF patients (p = 0.12).

CONCLUSION

LLIF at L4-5 increases lordosis at the operated level, with compensatory decrease at L5-S1 but not L3-4. This reciprocal loss at adjacent L5-S1 may explain inconsistent improvement in lumbar lordosis (PI-LL) post L4-5 fusion.

Comparing OLIF Combined with Lateral Screw Fixation versus Minimally Invasive TLIF for Treating Single-Level Degenerative Lumbar Spondylolisthesis: A Retrospective Cohort Study

BACKGROUND

 The present study aimed to compare the clinical and radiologic outcomes of oblique lumbar interbody fusion (OLIF) combined with lateral screw fixation and minimally invasive transforaminal lumbar interbody fusion (Mis-TLIF) for the treatment of single-level degenerative lumbar spondylolisthesis (DLS).

METHODS

 Data regarding clinical and radiologic outcomes for single-level DLS treated using OLIF combined with lateral screw fixation or Mis-TLIF between November 2017 and June 2020 were retrospectively analyzed.

RESULTS

 Seventy-five patients with single-level DLS (≥2 years' follow-up) were included and divided into two groups according to the surgical method used: OLIF (n = 33) and Mis-TLIF (n = 42). Operative time, intraoperative blood loss, and length of hospital stay were significantly lower in the OLIF group than that in the Mis-TLIF group. There were no significant differences in preoperative low back pain (LBP), leg pain (LP), visual analog scale (VAS) scores, and Oswestry Disability Index (ODI) between the two groups, although the OLIF group had significantly lower LBP VAS scores at 1, 3, and 6 months postoperatively. Additionally, the LP VAS score was significantly lower in the Mis-TLIF group than that in the OLIF group at 1 month postoperatively, and the ODI of the OLIF group at 3 months postoperatively was significantly lower than that of the Mis-TLIF group. There was no significant difference in the preoperative and postoperative lumbar lordosis angles between the two groups, whereas the postoperative surgical segmental lordosis angle and disk height (at 1, 6, 12, and 24 months) in the OLIF group were significantly higher than those in the Mis-TLIF group. Additionally, there was no significant difference in complication rates between the two groups (18.2% in the OLIF group vs. 11.9% in the Mis-TLIF group; p = 0.520).

CONCLUSION

 OLIF combined with lateral screw fixation yielded better clinical and radiologic outcomes than Mis-TLIF in patients with single-level DLS.

Robotic endoscopic transforaminal lumbar interbody fusion: A single institution case series

Background

Robotic-assisted, endoscopic transforaminal lumbar interbody fusion (RE-TLIF) is a promising, minimally invasive surgical option for degenerative lumbar spondylosis/spondylolisthesis; however, outcomes data and efficacy are limited, especially in multilevel disease. Here, we present the first reported series of patients that underwent either single or multilevel RE-TLIF.

Methods

A retrospective review was performed on 23 consecutive patients who underwent a single level or multilevel RE-TLIF by a single surgeon. Variables included demographics, perioperative results, pain scores, and functional outcome scores.

Results

Eighteen patients (78.3 %) underwent single level RE-TLIF and 5 patients (21.7 %) underwent multilevel RE-TLIF. The median reduction of visual analog scale (VAS) for low back pain (LBP) of all subjects was 6 (IQR = 4.5, 6.5) with no significant difference between single level and multilevel RE-TLIF (p = 0.565). The median reduction of VAS for leg pain of all subjects 7 (IQR = 6, 8) with no significant difference between single level and multilevel RE-TLIF (p = 0.702). Median blood loss was 25 cc (IQR = 25, 25) and 50 cc (IQR = 25, 100) for single and multilevel RE-TLIF, respectively (p = 0.025), whereas median length of stay was 1 (IQR = 1, 1; mean = 1.0 ± 00.18) days and 1 (IQR = 1, 2; mean = 1.4 ± 00.54) days, respectively (p = 0.042). One major complication was observed requiring reoperation for demineralized bone matrix migration resulting in an L5 radiculopathy.

Conclusions

Single and multi-level RE-TLIF appears to be a safe and efficacious approach with comparable outcomes to open and other minimally invasive approaches. Additionally, we observed favorable accuracy in robot-assisted pedicle screw, endoscope, and interbody device placement.

Determining Prior Authorization Approval for Lumbar Stenosis Surgery With Machine Learning

STUDY DESIGN

Medical vignettes.

OBJECTIVES

Lumbar spinal stenosis (LSS) is a degenerative condition with a high prevalence in the elderly population, that is associated with a significant economic burden and often requires spinal surgery. Prior authorization of surgical candidates is required before patients can be covered by a health plan and must be approved by medical directors (MDs), which is often subjective and clinician specific. In this study, we hypothesized that the prediction accuracy of machine learning (ML) methods regarding surgical candidates is comparable to that of a panel of MDs.

METHODS

Based on patient demographic factors, previous therapeutic history, symptoms and physical examinations and imaging findings, we propose an ML which computes the probability of spinal surgical recommendations for LSS. The model implements a random forest model trained from medical vignette data reviewed by MDs. Sets of 400 and 100 medical vignettes reviewed by MDs were used for training and testing.

RESULTS

The predictive accuracy of the machine learning model was with a root mean square error (RMSE) between model predictions and ground truth of .1123, while the average RMSE between individual MD's recommendations and ground truth was .2661. For binary classification, the AUROC and Cohen's kappa were .959 and .801, while the corresponding average metrics based on individual MD's recommendations were .844 and .564, respectively.

CONCLUSIONS

Our results suggest that ML can be used to automate prior authorization approval of surgery for LSS with performance comparable to a panel of MDs.

Single-center pilot study of remote therapeutic monitoring in patients with operative spinal pathologies

OBJECTIVES

Spine pathology affects a significant portion of the population, leading to neck and back pain, impacting quality of life, and potentially requiring surgical intervention. Current pre- and postoperative monitoring methods rely on patient reported outcome (PRO) measures and lack continuous objective data on patients' recoveries. Remote therapeutic monitoring (RTM) using wearable devices offers a promising solution to bridge this gap, providing real-time physical function data. This study aims to assess the feasibility and correlation between changes in physical function and daily activity levels using RTM for individuals with operative spinal pathologies.

METHODS

A single-center pilot study involving 21 participants with operative spinal pathologies was conducted at an academic hospital. Participants were provided Bluetooth-enabled Fitbit Inspire 2 activity trackers and asked to wear them daily for 100 days. The Healthcare Recovery Solutions (HRS) mobile application facilitated remote administration of the PROMIS - Physical Function Short Form 6b PROs questionnaire at days 1, 30, and 90. Linear regression, Students' paired T tests, and one-way ANOVA were used to analyze collected data.

RESULTS

Average compliance with RTM was found to be 82.4% compared to only 48% for PROMs. Changes in daily steps were moderately positively correlated with changes in PROs at both 30 and 90 days. Participant satisfaction with RTM was high, and responses indicated greater satisfaction with RTM compared to PROMs.

CONCLUSIONS

RTM offers continuous and objective data collection, presenting a potential solution to the limitations of intermittent clinical assessments and self-reported outcomes. The study demonstrated a moderate correlation between changes in activity levels and changes in PROs, suggesting that RTM data could serve as a surrogate for PROs. Participants' high compliance and satisfaction with RTM underscore its feasibility and potential clinical utility. This study lays the groundwork for larger future investigations into the clinical benefits and broader application of RTM in spine care.

Regenerative therapy in geriatric patients with low back pain

Low back pain (LBP) is a prevalent and debilitating condition, particularly among older adults, with degenerative spinal disease being a major contributor. Regenerative therapy, which aims to repair and regenerate damaged spinal structures, has shown promise in providing long-term pain relief and functional improvement. This review focuses on the application and efficacy of regenerative therapies such as mesenchymal stem cells, platelet-rich plasma, and atelocollagen in older patients with LBP. Despite the potential benefits, there is a notable scarcity of studies specifically targeting the older population, and those available often have small sample sizes and limited age-related analyses. Our findings underscore the need for more comprehensive and well-designed clinical trials to evaluate the effectiveness of these therapies in older patients. Future research should prioritize larger age-specific studies to establish regenerative therapy as a viable and effective treatment option for LBP in the aging population.

Quantification of cauda equina nerve root dispersion through radiomics features in weight-bearing MRI in normal subjects and spinal canal stenosis patients

OBJECTIVE

To quantify the distribution of cauda equina nerve roots in supine and upright positions using manual measurements and radiomics features both in normal subjects and in lumbar spinal canal stenosis (LSCS) patients.

METHODS

We retrospectively recruited patients who underwent weight-bearing MRI in supine and upright positions for back pain. 3D T2-weighted isotropic acquisition (3D-HYCE) sequences were used to develop a 3D convolutional neural network for identification and segmentation of lumbar vertebrae. Para-axial reformatted images perpendicular to the spinal canal and parallel to each vertebral endplate were automatically extracted. From each level, we computed the maximum antero-posterior (AP) and latero-lateral (LL) dispersion of nerve roots; further, radiomics features were extracted to quantify standardized metrics of nerve root distribution.

RESULTS

We included 16 patients with LSCS and 20 normal subjects. In normal subjects, nerve root AP dispersion significantly increased from supine to upright position (p < 0.001, L2-L5 levels), and radiomics features showed an increase in non-uniformity. In LSCS subjects, in the upright position AP dispersion of nerve roots and entropy-related features increased caudally to the stenosis level (p < 0.001) and decreased cranially (p < 0.001). Moreover, entropy-related radiomics features negatively correlated with pre-operative Pain Numerical Rating Scale. Comparison between normal subjects and LSCS patients showed a difference in AP dispersion and increase of variance cranially to the stenosis level (p < 0.001) in the upright position.

CONCLUSIONS

Nerve root distribution inside the dural sac changed between supine and upright positions, and radiomics features were able to quantify the differences between normal and LSCS subjects.

CLINICAL RELEVANCE STATEMENT

The distribution of cauda equina nerve roots and the redundant nerve root sign significantly varies between supine and upright positions in normal subjects and spinal canal stenosis patients, respectively. Radiomics features quantify nerve root dispersion and correlates with pain severity.

KEY POINTS

• Weight-bearing MRI depicts spatial distribution of the cauda equina in both supine and upright positions in normal subjects and spinal stenosis patients. • Radiomics features can quantify the effects of spinal stenosis on the dispersion of the cauda equina in the dural sac. • In the orthostatic position, dispersion of nerve roots is different in lumbar spinal stenosis patients compared to that in normal subjects; entropy-related features negatively correlated with pre-operative Pain Numerical Rating Scale.

Deep Learning-based Image Enhancement Techniques for Fast MRI in Neuroimaging

Despite its superior soft tissue contrast and non-invasive nature, MRI requires long scan times due to its intrinsic signal acquisition principles, a main drawback which technological advancements in MRI have been focused on. In particular, scan time reduction is a natural requirement in neuroimaging due to detailed structures requiring high resolution imaging and often volumetric (3D) acquisitions, and numerous studies have recently attempted to harness deep learning (DL) technology in enabling scan time reduction and image quality improvement. Various DL-based image reconstruction products allow for additional scan time reduction on top of existing accelerated acquisition methods without compromising the image quality.

Amphiphilic NLC-Gel formulation loaded with Sebacoyl dinalbuphine ester and Nalbuphine for localized postoperative pain management

Opioids are powerful analgesics; however, their significant systemic adverse effects and the need for frequent administration restrict their use. Nalbuphine (NA) is a κ-agonist narcotic with limited adverse effects, but needs to be frequently administrated due to its short elimination half-life. Whereas sebacoyl dinalbuphine ester (SDE) is a NA prodrug, which can effectively prolong the analgesic effect, but lacks immediate pain relief. Therefore, in this study, a rapid and sustained local delivery formulation to introduce NA and SDE directly into surgical sites was developed. An amphiphilic nanostructured lipid carrier (NLC) poloxamer 407 (P407) gel (NLC-Gel) was developed to permit concurrent delivery of hydrophobic SDE from the NLC core and hydrophilic NA from P407, offering a dual rapid and prolonged analgesic effect. Benefiting from the thermal-sensitive characteristic of P407, the formulation can be injected in liquid phase and instantly transit into gel at wound site. NLC-Gel properties, including particle size, drug release, rheology, and stability, were assessed. In vivo evaluation using a rat spinal surgery model highlighted the effect of the formulation through pain behavior test and hematology analysis. NLC-Gels demonstrated an analgesic effect comparable with that of commercial intramuscular injected SDE formulation (IM SDE), with only 15 % of the drug dosage. The inclusion of supplemental NA in the exterior gel (PA12-Gel + NA) provided rapid drug onset owing to swift NA dispersion, addressing acute pain within hours along with prolonged analgesic effects. Our findings suggest that this amphiphilic formulation significantly enhanced postoperative pain management in terms of safety and efficacy.

Retrieval analysis of PEEK rods pedicle screw system: three cases analysis

PURPOSE

To analyze the characteristics of PEEK rods retrieved in vivo, specifically their wear and deformation, biodegradability, histocompatibility, and mechanical properties.

METHOD

Six PEEK rods were retrieved from revision surgeries along with periprosthetic tissue. The retrieved PEEK rods were evaluated for surface damage and internal changes using Micro-CT, while light and electron microscopy were utilized to determine any histological changes in periprosthetic tissues. Patient history was gathered from medical records. Two intact and retrieved PEEK rods were used for fatigue testing analysis by sinusoidal load to the spinal construct.

RESULTS

All implants showed evidence of plastic deformation around the screw-rod interface, while the inner structure of PEEK rods appeared unchanged with no visible voids or cracks. Examining images captured through light and electron microscopy indicated that phagocytosis of macrophages around PEEK rods was less severe in comparison to the screw-rod interface. The results of an energy spectrum analysis suggested that the distribution of tissue elements around PEEK rods did not differ significantly from normal tissue. During fatigue testing, it was found that the retrieved PEEK rods cracked after 1.36 million tests, whereas the intact PEEK rods completed 5 million fatigue tests without any failure.

CONCLUSION

PEEK rods demonstrate satisfactory biocompatibility, corrosion resistance, chemical stability, and mechanical properties. Nevertheless, it is observed that the indentation at the junction between the nut and the rod exhibits relatively weak strength, making it susceptible to breakage. As a precautionary measure, it is recommended to secure the nut with a counter wrench, applying the preset torque to prevent overtightening.

Examining the influence of body fat distribution on standing balance and functional performance in overweight female patients with degenerative lumbar disease

Introduction: Degenerative lumbar disease (DLD) is a prevalent disorder that predominantly affects the elderly population, especially female. Extensive research has demonstrated that overweight individuals (categorized by body fat distribution) have a higher susceptibility to developing DLD and an increased risk of falling. However, there is limited research available on the standing balance and functional performance of overweight females with DLD. Aims: To determine the impact of body fat distribution on standing balance and functional performance in overweight females with DLD. Methods: This cross-sectional study evaluated thirty females with DLD were categorized into three types of body fat distribution based on body mass index (BMI) and waist-hip ratio, specifically as android-type, gynoid-type, and normal weight groups. In addition, a control group of ten age-matched females with normal weight was recruited. The Visual Analogue Scale, Roland Morris Disability Questionnaire, Cobb angle (Determined using x-ray), and body composition (Determined using the InBody S10), were conducted only on the DLD groups. All participants were assessed standing balance in the anteroposterior and mediolateral directions. The functional assessments included timed-up-and-go and 5-times-sit-to-stand tests. Results: There were 10 people in each group. Android-type (Age = 65.00 ± 6.34 years; BMI = 26.87 ± 2.05 kg/m2), Gynoid-type (Age = 65.60 ± 4.99 years; BMI = 26.60 ± 1.75 kg/m2), Normal weight (Age = 65.70 ± 5.92 years; BMI = 22.35 ± 1.26 kg/m2), and Control (Age = 65.00 ± 5.23 years; BMI = 22.60 ± 1.12 kg/m2). The android-type group had higher body fat, visceral fat, and lower muscle mass (p < 0.05), along with an increased Cobb angle (p < 0.05). They showed greater ellipse area, total excursion, and mean distance in the anteroposterior direction (p < 0.05). During the functional performance assessments, the android-type group had longer durations in both the 5-times-sit-to-stand and timed-up-and-go tasks (p < 0.05). Conclusion: Our study found that android-type overweight individuals showed postural instability, reduced functional performance, and insufficient lower limb muscle strength and mass. These findings might help physical therapists in planning interventions, as they imply that patients with DLD may require specific types of standing balance training and lower extremities muscle-strengthening based on their body fat distribution. Clinical Trial Registration: ClinicalTrials.gov, identifier NCT05375201.

Associations of overweight/obesity with patient-reported outcome measures after oblique lumbar interbody fusion

Background

Oblique lateral interbody fusion (OLIF) combined with transpedicular screw fixation has been practiced for degenerative spinal diseases of elderly patients for years. However, overweight patients have been shown to have longer operative times and more complications from surgery. The effect on clinical outcome is still uncertified. The objective of this study was to determine is overweight a risk factor to clinical outcome of OLIF combined with transpedicular screw fixation technique.

Material and methods

A retrospective study in patients submitted to OLIF combined with transpedicular screw fixation from January 2018 to August 2019 was conducted. VAS score, ODI score and EQ5D were measured before the operation and one year after the operation.

Results

A total of 111 patients were included with 48 patients in the non-obese group and 55 patients in the overweight/obese group. There was no significant difference between the two groups in gender, age, smoking history, hypertension, chronic kidney disease and diabetes mellitus. Overweight/obese group has higher BMI (28.4 vs. 22.7, p < 0.001) than non-obese group. There was no difference between the two groups in pre-operative VAS score, ODI score and EQ5D score. However, the healthy weight group improved much more than the overweight score in VAS score, ODI score and EQ5D score.

Conclusion

The overweight/obese patient group had clinical outcomes worse than the non-obese group in terms of pain relief and life functions.

Orthobiologic Management Options for Degenerative Disc Disease

Degenerative disc disease (DDD) is a pervasive condition that limits quality of life and burdens economies worldwide. Conventional pharmacological treatments primarily aimed at slowing the progression of degeneration have demonstrated limited long-term efficacy and often do not address the underlying causes of the disease. On the other hand, orthobiologics are regenerative agents derived from the patient's own tissue and represent a promising emerging therapy for degenerative disc disease. This review comprehensively outlines the pathophysiology of DDD, highlighting the inadequacies of existing pharmacological therapies and detailing the potential of orthobiologic approaches. It explores advanced tools such as platelet-rich plasma and mesenchymal stem cells, providing a historical overview of their development within regenerative medicine, from foundational in vitro studies to preclinical animal models. Moreover, the manuscript delves into clinical trials that assess the effectiveness of these therapies in managing DDD. While the current clinical evidence is promising, it remains insufficient for routine clinical adoption due to limitations in study designs. The review emphasizes the need for further research to optimize these therapies for consistent and effective clinical outcomes, potentially revolutionizing the management of DDD and offering renewed hope for patients.

Unveiling interactions between intervertebral disc morphologies and mechanical behavior through personalized finite element modeling

Introduction: Intervertebral Disc (IVD) Degeneration (IDD) is a significant health concern, potentially influenced by mechanotransduction. However, the relationship between the IVD phenotypes and mechanical behavior has not been thoroughly explored in local morphologies where IDD originates. This work unveils the interplays among morphological and mechanical features potentially relevant to IDD through Abaqus UMAT simulations. Methods: A groundbreaking automated method is introduced to transform a calibrated, structured IVD finite element (FE) model into 169 patient-personalized (PP) models through a mesh morphing process. Our approach accurately replicates the real shapes of the patient's Annulus Fibrosus (AF) and Nucleus Pulposus (NP) while maintaining the same topology for all models. Using segmented magnetic resonance images from the former project MySpine, 169 models with structured hexahedral meshes were created employing the Bayesian Coherent Point Drift++ technique, generating a unique cohort of PP FE models under the Disc4All initiative. Machine learning methods, including Linear Regression, Support Vector Regression, and eXtreme Gradient Boosting Regression, were used to explore correlations between IVD morphology and mechanics. Results: We achieved PP models with AF and NP similarity scores of 92.06\% and 92.10\% compared to the segmented images. The models maintained good quality and integrity of the mesh. The cartilage endplate (CEP) shape was represented at the IVD-vertebra interfaces, ensuring personalized meshes. Validation of the constitutive model against literature data showed a minor relative error of 5.20%. Discussion: Analysis revealed the influential impact of local morphologies on indirect mechanotransduction responses, highlighting the roles of heights, sagittal areas, and volumes. While the maximum principal stress was influenced by morphologies such as heights, the disc's ellipticity influenced the minimum principal stress. Results suggest the CEPs are not influenced by their local morphologies but by those of the AF and NP. The generated free-access repository of individual disc characteristics is anticipated to be a valuable resource for the scientific community with a broad application spectrum.

Transforaminal posterior lumbar interbody fusion microscopic safe operating area: a three-dimensional model study based on computed tomography imaging

BACKGROUND

Endoscopic spine lumbar interbody fusion (Endo-LIF) is well-regarded within the academic community. However, it presents challenges such as intraoperative disorientation, high rates of nerve damage, a steep learning curve, and prolonged surgical times, often occurring during the creation of the operative channel. Furthermore, the undefined safe operational zones under endoscopy continue to pose risks to surgical safety. We aimed to analyse the anatomical data of Kambin's triangle via CT imaging to define the parameters of the safe operating area for transforaminal posterior lumbar interbody fusion (TPLIF), providing crucial insights for clinical practice.

METHODS

We selected the L4-L5 intervertebral space. Using three-dimensional (3D), we identified Kambin's triangle and the endocircle within it, and recorded the position of point 'J' on the adjacent facet joint as the centre 'O' of the circle shifts by angle 'β.' The diameter of the inscribed circle 'd,' the abduction angle 'β,' and the distances 'L1' and 'L2' were measured from the trephine's edge to the exiting and traversing nerve roots, respectively.

RESULTS

Using a trephine with a diameter of 8 mm in TPLIF has a significant safety distance. The safe operating area under the TPLIF microscope was also clarified.

CONCLUSIONS

Through CT imaging research, combined with 3D simulation, we identified the anatomical data of the L4-L5 segment Kambin's triangle, to clarify the safe operation area under TPLIF. We propose a simple and easy positioning method and provide a novel surgical technique to establish working channels faster and reduce nerve damage rates. At the same time, according to this method, the Kambin's triangle anatomical data of the patient's lumbar spine diseased segments can be measured through CT 3D reconstruction of the lumbar spine, and individualised preoperative design can be conducted to select the appropriate specifications of visible trephine and supporting tools. This may effectively reduce the learning curve, shorten the time operation time, and improve surgical safety.

Risk factors affecting spinal fusion: A meta-analysis of 39 cohort studies

PURPOSE

We performed a meta-analysis to identify risk factors affecting spinal fusion.

METHODS

We systematically searched PubMed, Embase, and the Cochrane Library from inception to January 6, 2023, for articles that report risk factors affecting spinal fusion. The pooled odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using fixed-effects models for each factor for which the interstudy heterogeneity I2 was < 50%, while random-effects models were used when the interstudy heterogeneity I2 was ≥ 50%. Using sample size, Egger's P value, and heterogeneity across studies as criteria, we categorized the quality of evidence from observational studies as high-quality (Class I), moderate-quality (Class II or III), or low-quality (Class IV). Furthermore, the trim-and-fill procedure and leave-one-out protocol were conducted to investigate potential sources of heterogeneity and verify result stability.

RESULTS

Of the 1,257 citations screened, 39 unique cohort studies comprising 7,145 patients were included in the data synthesis. High-quality (Class I) evidence showed that patients with a smoking habit (OR, 1.57; 95% CI, 1.11 to 2.21) and without the use of bone morphogenetic protein-2 (BMP-2) (OR, 4.42; 95% CI, 3.33 to 5.86) were at higher risk for fusion failure. Moderate-quality (Class II or III) evidence showed that fusion failure was significantly associated with vitamin D deficiency (OR, 2.46; 95% CI, 1.24 to 4.90), diabetes (OR, 3.42; 95% CI, 1.59 to 7.36), allograft (OR, 1.82; 95% CI, 1.11 to 2.96), conventional pedicle screw (CPS) fixation (OR, 4.77; 95% CI, 2.23 to 10.20) and posterolateral fusion (OR, 3.63; 95% CI, 1.25 to 10.49).

CONCLUSIONS

Conspicuous risk factors affecting spinal fusion include three patient-related risk factors (smoking, vitamin D deficiency, and diabetes) and four surgery-related risk factors (without the use of BMP-2, allograft, CPS fixation, and posterolateral fusion). These findings may help clinicians strengthen awareness for early intervention in patients at high risk of developing fusion failure.

Super-elderly, spinal surgery, evaluating the risks and benefits: a retrospective single-centre cohort study

INTRODUCTION

An increasingly ageing population presents emerging healthcare challenges. Adequate clinical evaluation and understanding of outcome-predicting factors are integral to delivering safe spinal surgery to super-elderly patients.

AIM

To evaluate spine surgery outcomes in patients aged 80 or above.

METHODS

We retrospectively evaluated patients 80 years and above who underwent elective or emergency spinal surgery between 2017 and 2022. The Eurospine Surgery Classification (ESC) was used to classify operations into Large, Medium, and Small. We calculated and compared Clinical Frailty Scores (CFS) pre- and post-operatively.

RESULTS

Two hundred forty-five patients met the inclusion criteria. Most were male (n = 145). The age range was 80 to 99 (mean 83.3). Most operations were elective (n = 151, 62%). In our cohort, 211, 22, 10,2 and 1 patients had degenerative, trauma, tumour, infective and vascular pathologies, respectively. According to the Eurospine classification, 201 (82.0%) had Minor spine surgery (63 emergently and 138 electively), 38 had Medium surgery (15.5% - 30 emergently and 8 electively), and 6 had Large surgery (2.4% - 1 emergently and 5 electively). 163 (66.5%) were discharged or under follow-up. There were 11 in-patient mortalities (4.5%). Outpatient mortality was 51 (20.8%), with the median time from surgery to death being 504.5 days, all the outpatient mortalities were neither non-spinal pathology nor spinal surgical related. CFS improved across the cohort, from 5 pre-operatively to 4 post-operatively (p < 0.001).

CONCLUSION

Spine surgery in those over the 80s can be performed safely and improve their quality of life, as demonstrated by improvements in the CFS. Good patient selection and adequate pre-operative workup is essential, although it may not be possible in emergencies.

Is endoscopic technique an effective and safe alternative for lumbar interbody fusion? A systematic review and meta-analysis

Study design

Systematic review; meta-analysis.

Purpose

Lumbar degenerative disease is frequent and has a tremendous impact on patients' disability and quality-of-life. Open and minimally invasive procedures have been used to achieve adequate decompression and fusion. Endoscopic lumbar interbody fusion (Endo-LIF) is emerging as an alternative, trying to reduce morbidity, while achieving comparable to superior clinical outcomes. The aim of this work is to perform a systematic review and meta-analysis to investigate how Endo-LIF compares to open or minimally invasive procedures.

Methods

Electronic databases (MEDLINE, Scopus, Web of Science, Cochrane) were systematically reviewed using the query: '(percutaneous OR endoscop*) AND (open OR minimal* invasive) AND lumbar AND fusion'. PRISMA guidelines were followed.

Results

Twenty-seven articles were included (25 cohort study, 1 quasi-experimental study, and 1 randomized control trial; for meta-analytical results, only observational studies were considered). Endo-LIF conditioned longer operative time, with significantly lower blood loss, bedtime, and hospital length of stay. Early post-operative back pain favored endoscopic techniques. Endo-LIF and non-Endo-LIF minimally invasive surgery displayed comparable results for most back and leg pain or disability outcomes, despite Endo-LIF having been associated with higher disability at late follow-up (versus Open-LIF). No differences were found regarding fusion rates, cage subsidence, or adverse events. Definitive conclusions regarding fusion rate cannot be drawn due to low number of studies and unstandardized fusion definition.

Conclusion

Endo-LIF is an effective and safe alternative to conventional lumbar interbody fusion procedures. Evidence shortcomings may be addressed, and future randomized control trials may be performed to compare techniques and to validate results.

Genotoxic parameters of human degenerated intervertebral discs are linked to the pathogenesis of disc degeneration

BACKGROUND

Degenerative disc disease (DDD) is a prevalent disorder that brings great incapacity and morbidity to the world's population. Its pathophysiology is not fully understood. DNA damage can influence this process, but so far, there have been few studies to evaluate this topic and its true importance in DDD, as well as whether there is a relation between degeneration grade and DNA damage. The objective of this study is to evaluate the degree of damage to the DNA and the relation to the severity of DDD and measure its response to this insult compared to live/dead cell parameters and reactive oxygen species activity in human discs.

METHODS

An experimental study was performed with 15 patients with grade IV or V Pfirrmann classification who underwent spinal surgery. Five patients were operated on two levels, resulting in 20 samples that were submitted to the comet assay to measure DNA damage. Of these, six samples were submitted to flow cytometry, and apoptosis, necrosis, cell membrane integrity, intracellular esterase activity, reactive oxygen species (ROS), caspase 3 and mitochondrial membrane potential were evaluated.

RESULTS

All samples had DNA damage, and the average of index damage (ID) was 78.1 (SD±65.11) and frequency damage (FD) was 49.3% (SD±26.05%). There was no statistical difference between the Pfirrmann grades and genotoxic damage. Likewise, all samples that underwent flow cytometry showed apoptosis and ROS to many different degrees.

CONCLUSIONS

DNA damage occurs in high-grade degeneration of human discs and contributes to activation of the apoptosis pathway and ROS production that can accelerate disc degeneration.

Comparison of predictive value for cage subsidence between MRI-based endplate bone quality and vertebral bone quality scores following transforaminal lumbar interbody fusion: a retrospective propensity-matched study

BACKGROUND CONTEXT

Cage subsidence after lumbar fusion can lead to many adverse outcomes. Low bone mineral density (BMD) is a widely recognized risk factor for cage subsidence. Conventional methods can predict and evaluate BMD, but there are many shortcomings. Recently, MRI-based assessment of bone quality in specific parts of the vertebral body has been proposed, including scores for vertebral bone quality (VBQ) and endplate bone quality (EBQ). However, the predictive accuracy of the two scoring systems for cage subsidence after transforaminal lumbar interbody fusion (TLIF) remains unknown. Therefore, we investigated MRI-based VBQ and EBQ scores for assessing bone quality and compared their predictive value for cage subsidence after TLIF.

PURPOSE

To compare the predictive value between MRI-based VBQ and EBQ scores for cage subsidence after TLIF.

STUDY DESIGN/SETTING

A retrospective case-control study.

PATIENTS SAMPLE

Patients with degenerative lumbar diseases underwent single-level TLIF at our medical center between 2014 and 2020, all of whom had preoperative MRIs available.

OUTCOMES MEASURES

Cage subsidence, disc height, VBQ score, EBQ score, upper and lower vertebral body bone quality (UL-VBQ) score.

METHODS

Data were retrospectively examined for a consecutive sample of 346 patients who underwent TLIF at our medical center between 2014 and 2020. Patients who subsequently experienced cage subsidence or not were matched to each other based on propensity scoring, and the two matched groups (52 patients each) were compared using conditional logistic regression to investigate the association between the potential radiographic factors and cage subsidence. Scores for VBQ and EBQ were assessed for their ability to predict cage subsidence in the matched patients based on the area under the receiver operative characteristic curve (AUC).

RESULTS

Among matched patients, those who suffered cage subsidence had significantly higher VBQ score (3.7 vs 3.1, p<.001) and EBQ score (5.0 vs 4.3, p<.001), and regression linked greater risk of subsidence to higher VBQ score (OR 4.557, 95% CI 1.076-19.291, p=.039) and higher EBQ score (OR 5.396, 95% CI 1.158-25.146, p=.032). A cut-off VBQ score of 3.4 predicted the cage subsidence among matched patients with an AUC of 0.799, sensitivity of 84.6%, and specificity of 69.2%. A cut-off EBQ score of 4.7 predicted subsidence with an AUC of 0.829, sensitivity of 76.9%, and specificity of 82.7%.

CONCLUSION

Higher VBQ and EBQ scores are associated with a greater risk of cage subsidence following TLIF, and EBQ may perform better because of greater specificity.