Aims and Scope The Journal of Spine Surgery (JSS, J Spine Surg, Print ISSN: 2414-469X; Online ISSN: 2414-4630) is an open access, peer-reviewed journal dedicated to the field of spine surgery, science and clinical outcomes. Published quarterly from December 2015 to December 2025, JSS will transition to a monthly publication model, starting in January 2026. JSS has been indexed by Web of Science [Emerging Sources Citation Index (ESCI)], PubMed/PubMed Central and Scopus, and received its first impact factor of 2.3 for the year 2025. The primary objective of JSS is to provide critical analysis and a comprehensive overview of contemporary topics within the field of spine surgery. Each issue will welcome relevant spine topics through the categorized sections: Original Article, Review Article, Case Reports, Editorial Commentary, Guidelines, and Evidence Update. The second objective of the JSS is to facilitate and stimulate the discussion and sharing of pertinent clinical information amongst surgeons and physicians concerned with the surgical treatment of spinal disorders. Articles will be published both in print and online, which will be featured with surgical videos. The aim of the Journal is to provide a forum for the dissemination of progresses in all areas related to spinal disorders and surgical techniques worldwide. JSS is published by AME Publishing Company, with support from Wolters Kluwer (the journal content will be made available on Wolters Kluwer Health’s Lippincott and Ovid platforms). Indexing Journal of Spine Surgery is indexed and covered by Web of Science [Emerging Sources Citation Index (ESCI)] PubMed PubMed Central (PMC) Scopus Google Scholar Ovid Information for Authors JSS is a member of Committee on Publication Ethics (COPE) and it follows the Committee on Publication Ethics (COPE)'s guidelines and the ICMJE recommendations for the Conduct, Reporting, Editing, and Publication of Scholarly Work in Medical Journal. Manuscripts submitted must be the original work of the author(s) and must not be published previously or under consideration for publication elsewhere. Submission Turnaround Time In-house review: 1-3 weeks. External peer review: 1-3 months. Publication Ahead of Print: within 1 month after being accepted (with APC payment received). Formal publication: within 1-3 months after being accepted (with APC payment received). Original Articles are listed as priority. Publication Schedule Published quarterly from December 2015 to December 2025, JSS will transition to a monthly publication model, starting in January 2026. Open Access Statement This journal is a peer reviewed, open access journal. All content of the journal is published under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License (CC BY-NC-ND 4.0). All articles published open access will be immediately and permanently free for all to read, download, copy and distribute as defined by the applied license. Free access and usage Permitted third party reuse is defined by the CC BY-NC-ND 4.0 license. 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Example of statements in published articles: https://actr.amegroups.org/article/view/8875; https://med.amegroups.org/article/view/8358/html. Contact with Editorial Office Suki Tang, Corresponding Editor, Journal of Spine Surgery Email: jss@amegroups.com Hong Kong Office: Flat/RM C 16F, Kings Wing Plaza 1, NO. 3 on Kwan Street, Shatin, NT, Hong Kong, China. Publisher Information JSS is published by AME Publishing Company. Address: Hong Kong branch office: Flat/RM C 16F, Kings Wing Plaza 1, NO. 3 on Kwan Street, Shatin, NT, Hong Kong, China. Updated on July 10, 2026
A decade of impact: the Journal of Spine Surgery enters its next phase
Improving operating room turnover efficiency with a real-time workflow coordination software in adult degenerative spine surgery
Background: Operating room (OR) efficiency represents a critical determinant of surgical productivity, cost-effectiveness, workforce wellness, and patient access to care. Among its modifiable components, turnover time (TOT), the interval between patient exit and subsequent patient entry, is a key target for operational improvement. This study describes the impact of the S1 Pit Crew™ platform, a real-time, role-based OR workflow coordination software, on TOT using adult degenerative spine surgery as a representative test environment. Methods: This study examined prospectively collected perioperative and turnover workflow data from 51 consecutive elective adult degenerative spine surgery cases performed at a single hospital following S1 Pit Crew™ platform implementation. Baseline TOT was derived from institutional records of cases performed over the year preceding implementation and was used for descriptive comparison. The platform delivered real-time, role-specific task prompts and shared situational awareness across all perioperative team members via synchronized multi-device displays, enabling prospective collection of turnover and perioperative workflow data. A total of 24-time parameters were collected and aggregated into four key time interval durations including Stage 1: perioperative time interval #1 (dressing to wheels-out); Stage 2: turnover time (wheels-out to wheels-in); Stage 3: perioperative time interval #2 (wheels-in to incision); and total elapsed skin-to-skin time. Cases were stratified into initial (N=26) and subsequent (N=25) cohorts to assess efficiency with continued utilization and key time interval durations were also compared across procedure types, surgeon, OR, and case order. Results: Mean TOT was 26.5 minutes following platform implementation, compared with a baseline institutional average of 38.0 minutes, representing a 30.3% descriptive difference. TOT decreased significantly between the initial (28.9±7.7 minutes) and subsequent cohort (23.9±3.7 minutes) (P=0.02). Perioperative time intervals did not differ significantly between initial and subsequent cohorts (P>0.05). All key time interval durations were similar across procedure types, surgeons, ORs, and case order (P>0.05). Conclusions: After implementation of the S1 Pit Crew™ platform, mean TOT was descriptively 30.3% lower than the prior institutional baseline, with improvement observed with continued utilization and similar time durations across procedure types of varying complexity. Through standardizing workflow with real-time, shared task visibility, the platform functions as a behavioral coordination tool while also promoting accountability and enabling identification of inefficiencies. Real-time workflow coordination through the S1 Pit Crew™ platform may represent a scalable approach to improving OR efficiency across surgical environments.
Single-level cervical disc arthroplasty is associated with higher early subsequent surgery rates and similar adjacent segment disease rates compared with anterior cervical discectomy and fusion
Background: Cervical disc arthroplasty (CDA) is a motion-preserving alternative to anterior cervical discectomy and fusion (ACDF), but its comparative long-term durability remains debated. This study aimed to compare short- and long-term postoperative outcomes following single-level CDA versus ACDF. Methods: A retrospective propensity-matched cohort study was performed using a large national administrative database. Adult patients undergoing single-level CDA or ACDF without prior spine surgery were identified and matched 1:1, yielding 3,138 patients per cohort. Outcomes were assessed at 1, 2, 5, and 10 years postoperatively. Results: At 1 year, CDA was associated with lower rates of pulmonary embolism/deep venous thrombosis (PE/DVT) [0.6% vs. 1.2%; risk ratio (RR) 0.526, P=0.02] and neurovascular injury (0.4% vs. 1.3%; RR 0.333, P<0.001), while other short-term complications were similar. At 2 and 5 years, CDA demonstrated higher rates of subsequent cervical spine surgery (1.5% vs. 0.7%, P=0.003; 1.9% vs. 1.1%, P=0.02), although this difference was no longer significant at 10 years. CDA also showed lower long-term rates of infection, PE/DVT, and nerve injury. No significant differences were observed in adjacent segment disease (ASD) or cervical spondylolisthesis. Conclusions: Single-level CDA was associated with higher early revision and subsequent surgery rates and similar ASD rates compared with ACDF. Although CDA showed lower rates of select complications, these differences may not outweigh the increased intermediate-term reoperation burden.
Kyphoplasty for vertebral compression fractures: the blue zone effect
Background: Kyphoplasty effectively treats vertebral compression fractures (VCFs) but carries risks of perioperative complications and readmissions. Blue zones, regions characterized by longevity and reduced chronic disease, provide a unique opportunity to examine how lifestyle factors may influence surgical outcomes. This study investigated how patient demographics, health status, surgical factors, and geographic location, particularly residence in a blue zone, affected kyphoplasty outcomes. Methods: A retrospective cohort review of 372 patients undergoing kyphoplasty for VCFs from January 2009 to May 2025 was conducted at a single, tertiary care institution. Patients were divided into blue zone or non-blue zone by postal codes. 1:3 propensity score matching (PSM) was used to minimize bias and multivariable logistic regression analyzed outcomes. A 10-year Kaplan-Meier survival curve was formulated utilizing a log-rank test. Results: A total of 190 patients (175 non-blue zone and 15 blue zone patients) were available after exclusion. In the unmatched cohort, tobacco usage was associated with higher 30-day readmissions. Increased length of stay (LOS) was associated with higher American Society of Anesthesiologists (ASA) scores, older age, diabetes, mechanical expansion, and greater estimated blood loss (EBL). Thoracolumbar involvement increased neurological complications, while a bilateral approach reduced incidence. Blue zone patients had significantly lower alcohol (0% vs. 34–64%) and tobacco use (7% vs. 43–47%) than non-blue zone patients in both unmatched and 1:3 PSM cohorts. No other significant differences in outcomes were observed. Conclusions: Our findings reinforce the significance of traditional risk factors including age, ASA score, diabetes, and tobacco use, as key indicators of kyphoplasty outcomes. Blue zone kyphoplasty patients demonstrated markedly healthier lifestyles, such as reduced alcohol and tobacco use. The present small-sized matched analyses demonstrated that while lifestyle and environmental factors may delay onset of chronic disease and VCF occurrence, no detectable association was identified between blue zone residence and kyphoplasty outcomes.
The Konakondla-Telfeian-Shen (KTS) Pyramid: a safe entry zone for ventral thoracic pathologies
Background: Transforaminal (TF) endoscopic access to the lumbar spine has long relied on Kambin’s triangle as a posterolateral safe zone. As endoscopic indications expand, there are fundamental differences in thoracic anatomy that Kambin’s triangle does not account for, including smaller foraminal dimensions, the presence of the spinal cord, cranio-caudal pedicle angulation, and the rib head-costovertebral complex. To date, no formal anatomic framework exists to standardize thoracic TF planning. The objective of this study is to define and describe a three-dimensional thoracic TF working corridor, the Konakondla-Telfeian-Shen (KTS) Thoracic Pyramid, and to propose a standardized anatomic language and preoperative planning framework for endoscopic access to ventral thoracic pathology. Methods: The thoracic TF corridor is conceptualized as a six-faced three-dimensional volume. Level-dependent anatomic constraints, including the rib head–costovertebral complex, pedicle morphology, spinal cord position, and segmental vascular anatomy, are incorporated. Variations due to degeneration, fusion, prior surgery, and vascular anatomy are discussed within this geometric framework. Results: The KTS Pyramid defines a reproducible, level-specific posterolateral access corridor to the ventral thoracic canal. The corridor predictably narrows from T12 to T1 as the rib head and costovertebral joint migrate cranially toward the disc plane and pedicle angulation increases. This framework identifies which anatomic “face” of the pyramid limits access at each thoracic level. Conclusions: The KTS Pyramid provides a formal geometric and anatomic description of a thoracic TF working corridor. By standardizing thoracic endoscopic planning with level-specific boundaries and terminology, this framework supports safer access to ventral thoracic pathology, shortens the learning curve, and enables consistent communication, training, and future comparative research in thoracic endoscopic spine surgery.
Impact of incidental thoracic spinal stenosis on outcomes following lumbar fusion: propensity score-matched cohort study
Background: Incidental thoracic spinal stenosis (TSS) is increasingly identified on whole-spine imaging, but its clinical significance in patients undergoing lumbar fusion remains unclear. Methods: A retrospective propensity score-matched cohort study was conducted using a prospectively maintained registry [2010–2023] at a single tertiary centre. Patients with incidental radiologic TSS were matched 1:4 to controls without TSS based on age, sex, body mass index, and number of fused levels. Outcomes included Visual Analogue Scale (VAS), Oswestry Disability Index (ODI), North American Spine Society (NASS), and 36-Item Short Form Health Survey (SF-36) at baseline, 6 months, and 2 years. Results: Both groups demonstrated meaningful improvements in pain, disability, and quality-of-life outcomes at 6 months and 2 years. No significant between-group differences were observed in pain, disability, or quality-of-life outcomes at 6 months or 2 years (all P>0.05). During follow-up, 9/27 patients (33.3%) with TSS required thoracic surgery, whereas none in the control group did. Conclusions: In this propensity score-matched cohort, no statistically significant differences in lumbar fusion outcomes were detected between patients with and without incidental radiologic TSS at 6 months or 2 years. However, the subsequent thoracic surgery rate of 33.3% suggests that incidental TSS should not be considered clinically benign and may warrant ongoing surveillance for neurological progression.
Does adult lumbar scoliosis affect spine T-score accuracy in osteoporosis diagnosis?—a cross-sectional study of adults aged 50 years and older
Background: Dual-energy X-ray absorptiometry (DEXA) is the gold standard for assessing bone mineral density (BMD) and diagnosing osteoporosis (T-score ≤−2.5). Lumbar spine T-scores are often used when hip measurements are unavailable or unreliable. However, degenerative spinal changes can artifactually elevate lumbar spine BMD, leading to discordance between spine and hip T-scores and potential misclassification of osteoporosis. The impact of adult degenerative scoliosis on this discordance remains poorly defined. This study evaluates the association between lumbar scoliosis and spine-hip T-score discordance in adults ≥50 years. Methods: A retrospective cross-sectional study included consecutive adults ≥50 years who underwent DEXA scans over a 4-year period at a university hospital. Patients with secondary causes of osteoporosis were excluded. Participants were grouped by presence or absence of scoliosis. Spine and hip T-scores were recorded and classified as no, minor, or major discordance. No discordance indicated no grade difference between sites. Minor discordance referred to a one-grade difference (normal vs. osteopenia or osteopenia vs. osteoporosis). Major discordance referred to a two-grade difference (normal vs. osteoporosis). Results: A total of 6,969 patients were included; 91.6% were female with a mean age of 60.6 years. Scoliosis was present in 637 patients (9.1%), with a mean Cobb angle of 17° (range, 10–66°). Spine T-scores classified more patients as normal (43.0% vs. 31.1%) and fewer as osteopenic (41.5% vs. 48.9%) or osteoporotic (15.5% vs. 19.1%) compared with hip T-scores. Patients with scoliosis were older (67 vs. 60 years, P<0.001) and more likely female (94% vs. 91%, P<0.001). Spine-hip discordance was more frequent in scoliosis patients, with minor discordance in 44.1% vs. 39.0% and major discordance in 5.0% vs. 2.8% of non-scoliosis patients. Conclusions: Lumbar scoliosis is associated with increased spine-hip T-score discordance, limiting the reliability of lumbar spine measurements in osteoporosis assessment. These effects are more pronounced in older adults and females. Clinicians should interpret spine T-scores cautiously in the presence of scoliosis and prioritise hip measurements when assessing bone health or planning interventions where bone quality is critical.
Age predicts long-term functional outcomes following vertebroplasty for osteoporotic vertebral compression fractures
Background: Vertebroplasty provides effective pain relief for osteoporotic vertebral compression fractures; however, determinants of long-term functional recovery remain incompletely defined. This study aimed to evaluate baseline predictors of long-term patient-reported outcomes following vertebroplasty. Methods: Ninety-two patients who underwent percutaneous vertebroplasty between 2010 and 2022 with complete patient-reported outcome measures (PROMs) at baseline, 6 months, and 2 years were included. The primary outcome was Short Form-36 (SF-36) Physical Function at 2 years. Multivariable linear regression models adjusted for baseline PROMs were used to evaluate associations with age, sex, vertebral region, and number of treated levels. Results: Mean age was 76.5±8.4 years, and 82.6% were female. Significant improvements were observed in Oswestry Disability Index (ODI) scores (77.3 to 25.3), SF-36 Physical Function (9.2 to 41.8), and visual analogue scale (VAS) back pain scores (8.0 to 1.7) at 2 years (all P<0.001). Increasing age was independently associated with poorer 2-year SF-36 Physical Function [β=−17.45 per 10-year increase; 95% confidence interval (CI): −24.43 to −10.47; P<0.001]. Procedural variables were not associated with postoperative outcomes. Baseline physical function demonstrated moderate correlation with postoperative outcomes (r=0.40–0.44) but was not independently predictive after adjustment. Conclusions: Vertebroplasty was associated with sustained improvement in pain and function. Increasing age was the strongest observed independent predictor of poorer long-term physical function within this cohort, whereas procedural variables were not significantly associated with postoperative outcomes. These findings suggest that long-term functional recovery following vertebroplasty may be associated more strongly with patient-related than procedural factors within this cohort.
Comparative analysis of autograft vs. synthetic bone graft in spinal fusion: a systematic review and meta-analysis
Background: Autografts are regarded as the gold standard for spinal fusion owing to their capability to promote bone formation. However, synthetic bone grafts are gaining popularity for their consistency and avoidance of donor site complications. This meta-analysis compares the treatment results of autografts and synthetic bone grafts in spinal fusion procedures and evaluates their clinical effectiveness. Methods: The study adhered to PRISMA guidelines and conducted a comprehensive literature search. It compared autografts and synthetic bone grafts in spinal fusion by employing a random-effects model for meta-analysis, assessing publication bias, and evaluating the certainty of evidence using Grading, Reporting, Assessment, Development, and Evaluation (GRADE) guidelines, along with methodological quality through the risk of bias-2.0 (RoB-2.0) and Risk of Bias in Non-randomized Studies of Interventions (ROBINS-I) tools. Results: Following a thorough screening, nine studies fulfilled the inclusion criteria. In the subgroup analysis, the pooled effect size for the fusion rate between different types of synthetic bone graft [ceramics, i-Factor, demineralized bone matrix (DBM)] and compared with autograft was 1.24 odds ratio (OR) [95% confidence interval (CI): 0.77–2.02; P=0.38; I2=0%], success rate for ceramics, i-Factor, and bioactive glass was 1.78 OR (95% CI: 1.28–2.48; P=0.0006; I2=0%). The blood loss had an −0.88 standardized mean difference (SMD) (95% CI: −1.90 to 0.15; P=0.09; I2=87%). For reoperation, the effect size was 0.78 (95% CI: 0.37–1.68; P=0.53; I2=0%), and in the complications subgroup analysis (i-Factor, ceramic, bioactive glass), the pooled effect size was 0.82 (95% CI: 0.54–1.24; P=0.35; I2=0%). A funnel plot revealed publication bias, while most studies demonstrated minimal risk of bias. However, the certainty of evidence was low because of this bias and wide variance. Conclusions: Synthetic bone grafts can be a reliable alternative to autografts in spinal fusion, and the recommendation is weak due to low-certainty evidence. Meanwhile, further longitudinal studies are required to validate these findings.
Associations of paraspinal muscle quantity and quality with patient-reported outcomes in patients aged ≥85 years undergoing lumbar spine surgery: an exploratory retrospective study
Background: Population aging has driven an increase in lumbar spine surgery among the super-elderly. The associations of preoperative paraspinal muscle quantity and quality with patient-reported outcomes in patients aged ≥85 years undergoing lumbar spine surgery remain unclear. We therefore examined these associations at baseline and 1 year after surgery. Methods: This is a retrospective observational study. Forty-three patients aged ≥85 years undergoing surgery for degenerative lumbar disorders were studied. Preoperative L3 muscle quantity [paraspinal muscle index (PMI)] and quality [computed tomography (CT) attenuation (Hounsfield units, HU); magnetic resonance imaging (MRI)-based Goutallier grading] were assessed. Patient-reported outcome measures (PROMs) were collected preoperatively and at 1 year. Associations at baseline, 1 year, and change from baseline (Δ) were examined using Spearman correlations. Multivariable linear and baseline-adjusted Firth logistic regression assessed the preoperative Japanese Orthopaedic Association Back Pain Evaluation Questionnaire (JOABPEQ) low back pain score and treatment effectiveness, respectively. An exploratory receiver operating characteristic (ROC) analysis evaluated HU to identify low preoperative JOABPEQ low back pain scores (≤29). Results: PMI showed no statistically detectable association with any PROM in this sample. In separate exploratory multivariable models, HU and Goutallier grade showed nominal associations with the preoperative JOABPEQ low back pain score, whereas no statistically detectable association was observed for PMI; no muscle measure showed a statistically detectable association with treatment effectiveness after baseline adjustment. HU correlated positively with preoperative JOABPEQ low back pain (ρ=0.379, P=0.016), whereas Goutallier grade correlated inversely with the same PROM (ρ=−0.374, P=0.018) and with preoperative 8-Item Short Form Health Survey physical component summary (SF-8 PCS) (ρ=−0.307, P=0.048). In exploratory ROC analysis, HU showed fair discrimination for low JOABPEQ low back pain scores [area under the curve (AUC) =0.740, 95% confidence interval (CI): 0.586–0.893]; the data-derived cutoff of 33.7 HU requires external validation and is not ready for clinical application. Conclusions: In this small, single-center exploratory study, HU and Goutallier grade showed nominal associations with baseline pain-related disability, whereas PMI showed no statistically detectable association. No muscle measure showed a statistically detectable association with treatment effectiveness after baseline adjustment. Given limited power, no multiplicity adjustment, and potential selection bias, these findings require validation and should not guide preoperative decision-making.
Outcomes of 3D-printed titanium cages for surgical reconstruction in infectious spondylodiscitis: a systematic review
Background: Infectious spondylodiscitis remains a complex spinal condition that may require surgical debridement and interbody reconstruction in cases of instability, deformity, or failure of medical management. Conventional reconstructive options include titanium mesh cages (TMC) and polyetheretherketone (PEEK) cages; however, three-dimensional printed titanium (3DPT) cages have been increasingly adopted due to their porous architecture and potential to enhance osseointegration. The clinical performance of 3DPT cages in the setting of spinal infection has not been well defined. This study aimed to qualitatively summarise the currently available direct and contextual evidence regarding the use of 3DPT cages for spinal reconstruction in infectious spondylodiscitis. Methods: A systematic literature search of EMBASE, MEDLINE, and Cochrane Library was conducted up to December 2025. Studies reporting outcomes following spinal reconstruction using 3DPT cages in adult patients with infectious spondylodiscitis were included. Surgical parameters, radiological outcomes (including fusion and subsidence), and clinical outcomes were extracted and synthesised qualitatively due to heterogeneity in study design and outcome reporting. Results: A total of seven studies were included in this review. Among these, only one study directly evaluated 3DPT cages specifically in infectious spondylodiscitis, while the remaining studies provided indirect or contextual evidence from mixed-pathology or degenerative spinal cohorts. Overall, the available evidence remains highly limited and heterogeneous, with substantial variability in study design, outcome reporting, and follow-up duration. Conclusions: Only limited direct evidence is currently available regarding the use of 3DPT cages in infectious spondylodiscitis. While early reports suggest that these implants may be feasible for spinal reconstruction, the current evidence base is highly limited, indirect, and heterogeneous, preventing definitive conclusions regarding clinical effectiveness or superiority over conventional interbody devices. Therefore, these findings should be interpreted as hypothesis-generating rather than practice-changing. Future well-designed prospective and comparative studies with standardised outcome measures are required to better define their role and enable meaningful meta-analysis.
Does pre-operative psoas muscle cross-sectional area predict post-operative outcomes following lumbar spine fusion surgery?—a systematic review and narrative synthesis
Background: Low back pain remains a leading cause of disability globally, with surgical interventions commonly utilised as treatment. Rates of lumbar fusion surgery continue to rise, but poor outcomes remain common. Preoperative psoas muscle morphology has been proposed as a potential predictor of postoperative success. Evidence supporting a link between psoas morphology and outcomes post-fusion surgery is growing yet remains unclear. This systematic review and narrative synthesis aimed to evaluate whether pre-operative psoas muscle morphology predicts clinical and radiographic outcomes following lumbar fusion surgery. Methods: Five databases (MEDLINE, PubMed, CINAHL, Web of Science, and SportDiscus) were searched from inception to June 2025. Included studies assessed pre-operative psoas morphology [cross-sectional area (CSA), volume] and reported post-operative clinical (pain, disability, quality of life) or radiographic outcomes (fusion rates, alignment, complications). Risk of bias was assessed using Quality in Prognostic Studies (QUIPS), and certainty of evidence evaluated using Grading of Recommendations, Assessment, Development, and Evaluations (GRADE). Results: Sixteen retrospective cohort studies encompassing 2,250 patients were included. Overall, data indicates that psoas morphology is not a consistent predictor of outcomes following fusion procedures. A limited number of low-quality studies, however, suggest that the surgical approach may influence this relationship. Posterior fusion techniques showed some association where a larger psoas was linked to early improvements in pain and function, while lateral and anterior approaches demonstrated no relationship. Conclusions: Based on very low to low certainty evidence, routine pre-operative psoas assessment is not currently justified for predicting lumbar fusion outcomes. Higher-quality prospective studies are needed to clarify the prognostic value of psoas morphology in spine surgery.
Associations between preoperative biomarkers and patient-reported outcomes after single-level lumbar discectomy: a systematic review
Background: Single-level discectomy is among the most frequently performed spine procedures for radiculopathy due to disc herniation. Although most patients improve, a subset experiences suboptimal recovery, disability, or reoperation. Current preoperative risk stratification remains limited, highlighting the need for objective biomarkers that can improve the prediction of postoperative outcomes. The objective of this study is to review the effect of biomarkers on standard patient outcomes, identify consistencies and gaps in the literature, and outline priorities for biomarker panel standardization to support clinically meaningful prediction in discectomy. Methods: We conducted a systematic review in accordance with PRISMA guidelines. PubMed, Embase, and the Cochrane Library were searched from inception to August 27, 2025, using terms for discectomy procedures, serum/tissue biomarkers, and PROs. Eligible studies enrolled adults undergoing single-level discectomy, measured biomarkers pre- or intra-operatively, and reported associations with PROs such as Visual Analog Scale (VAS), Oswestry disability Index (ODI), or EuroQol 5-Dimension Questionnaire (EQ-5D). Three authors independently performed screening, data extraction, and risk-of-bias assessment. Risk of bias was assessed using the Newcastle-Ottawa scale for observational studies. Results: Eight studies met inclusion criteria. Given heterogeneity in biomarkers, assays, and outcome reporting, findings were synthesized narratively by biomarker class; quantitative meta-analysis was not feasible. Across cohorts, pro-inflammatory cytokines consistently predicted worse outcomes: higher preoperative interleukin (IL)-6 and tumor necrosis factor alpha (TNF-α) were associated with higher postoperative VAS and ODI scores, and higher preoperative IL-1β was associated with higher postoperative VAS scores. The acute phase reactant C-reactive protein (CRP) was associated with increased VAS scores. In addition, regulatory cytokine transforming growth factor beta 1 (TGF-β1) corresponded to worse postoperative VAS. In contrast, anti-inflammatory/type-2 signaling with higher IL-4 correlated with greater VAS improvement. Brain-derived neurotrophic factor (BDNF) was also inversely correlated with worse VAS scores in specific studies. Conclusions: Preoperative biomarker profiles provide prognostic value for patient outcomes following single-level discectomy. Standardized, prospective studies using multivariable biomarker panels are warranted to validate current findings and establish quantitative prognosis.
Intraoperative three-dimensional imaging-guided vertebral body stenting for cleft-associated very severe osteoporotic vertebral compression fractures: a surgical technique case series
Very severe osteoporotic vertebral compression fractures (vsOVCF) associated with intravertebral clefts represent a technically challenging subgroup of vertebral augmentation because of severe vertebral collapse, distorted intravertebral anatomy, and increased risk of cement leakage. Conventional fluoroscopy alone may be insufficient for accurate device positioning in these cases. We describe the surgical technique and technical utility of intraoperative three-dimensional (3D) imaging during vertebral body stenting (VBS) in three consecutive patients with cleft-associated vsOVCF without neurological deficits. All patients demonstrated intravertebral clefts on preoperative imaging. The procedure was performed using a bilateral transpedicular approach under biplanar fluoroscopy with adjunctive intraoperative 3D rotational imaging. Intraoperative 3D imaging enabled confirmation of balloon and stent positioning within residual cancellous bone rather than within the cleft cavity. Vertebral height restoration ranged from 9% to 18%, and all patients experienced marked pain relief, with mean Numerical Rating Scale scores improving from 8.0 preoperatively to 1.0 postoperatively. Cement leakage into the adjacent disc occurred in two cases, although no spinal canal leakage or symptomatic complications were observed. Postoperative computed tomography at 3 and 6 months demonstrated maintained vertebral height without recollapse, osteonecrosis, or implant-related complications. Intraoperative 3D imaging may serve as a useful technical adjunct for safer and more controlled VBS in anatomically complex fractures.
Depth-adapted portal design for unilateral biportal endoscopic discectomy in a morbidly obese patient (BMI 41): technical considerations
Morbid obesity increases operative depth and soft-tissue thickness in lumbar spine surgery, potentially complicating portal placement and working-corridor stability in unilateral biportal endoscopic (UBE) procedures. Although previous studies have reported acceptable clinical outcomes of UBE in obese patients, technical considerations for depth-adapted portal design and working corridor management at extreme operative depths have not been sufficiently described. A male patient in his late 20s, with a height of 183 cm and body weight of 137 kg (body mass index 41 kg/m2), presented with a large left L5/S1 lumbar disc herniation. Preoperative imaging suggested a deep operative corridor, with the relevant working depth ranging approximately from 80 to 100 mm depending on the laminar working area and the oblique trajectory toward the L5/S1 disc space. Because the skin contours were incompletely visualized on preoperative computed tomography (CT) due to the patient’s body habitus, intraoperative O-arm navigation was used as an adjunctive tool to confirm and refine the planned portal trajectories. Two 10-mm longitudinal skin incisions were created approximately 23 mm lateral to the midline, with an interportal distance of 35 mm. Adequate fascial release wider than the skin incisions was performed to reduce soft-tissue constraint at the fascial level. UBE discectomy was completed without dural injury or technical restriction, using standard UBE instruments. Postoperatively, radicular symptoms improved promptly without neurological deficits. This case illustrates depth-dependent amplification of soft-tissue constraints in UBE. As operative depth increases, small restrictions at the fascial level may proportionally narrow the functional working corridor. Adequate fascial release and thoughtful portal spacing may help preserve triangulation and facilitate irrigation outflow in deep operative fields. Rather than proposing a fixed portal template or requiring navigation, this report emphasizes individualized, depth-aware portal planning. Navigation may be useful in selected extreme cases when surface anatomy is difficult to evaluate reliably, but the same planning principles may also be applied using fluoroscopy and careful preoperative CT/MRI assessment. In morbidly obese patients with substantial operative depth, depth-aware portal planning combined with tailored fascial management may improve the reproducibility and technical stability of UBE discectomy. These findings should be interpreted as technical observations from a single case.
L5–S1 basivertebral nerve ablation for chronic vertebrogenic low back pain following lumbar fusion: a case report
Background: Basivertebral nerve ablation (BVNA) is an established treatment for vertebrogenic low back pain associated with Modic endplate changes, but trials and current on-label use have excluded patients with prior lumbar fusion. The clinical efficacy of BVNA has been established in the SMART (Surgical Multi-Center Assessment of RF Therapy) and INTRACEPT trials. Patients with prior lumbar fusion with symptomatic vertebrogenic low back pain were excluded from these major trials, but remain a clinically significant subgroup of patients who may benefit from BVNA. Case Description: A 55-year-old man presented with severe chronic axial low back pain persisting for more than 5 years after stand-alone L5–S1 interbody fusion performed in 1995. Pain was predominantly midline and mechanical, worsened by sitting, bending, lifting, and driving, and improved with standing or walking. He had failed extensive conservative and interventional therapies including nonsteroidal anti-inflammatory drugs, acetaminophen, epidural steroid injections, facet injections, medial branch blocks, sacroiliac joint injections, radiofrequency ablations, prolotherapy, acupuncture, and chiropractic care. Preoperative visual analog scale (VAS) score was 7/10 and Oswestry Disability Index (ODI) was 48%. Computed tomography showed a stable fusion construct without evidence of pseudoarthrosis or hardware complication. Magnetic resonance imaging demonstrated Modic type 2 endplate changes at L5–S1 adjacent to the fusion cages, supporting a vertebrogenic pain generator. The patient underwent fluoroscopically guided BVNA at L5 and S1 without complication. At 12 months, VAS was 3/10 and ODI 16%, exceeding the minimum clinically important difference (MCID) for spine surgery. The patient reported a 75% subjective improvement and return to unrestricted occupational activity. Conclusions: This case suggests that off-label BVNA may provide meaningful and durable relief in carefully selected post-fusion patients with persistent vertebrogenic pain and persistent Modic changes.
Rare intradural lumbar disc herniation at L1/2: a case report
Background: Intradural disc herniation (IDH) in the lumbar spine is an extremely rare condition, representing only a small percentage of all disc herniations. Despite advanced imaging techniques, IDH is often misdiagnosed as intradural tumor, disc herniation or migrated sequester. Definitive diagnosis is usually established intraoperatively and may be confirmed histologically. This case report describes an L1/2 IDH that was microsurgically removed with the assistance of intraoperative ultrasonography (IOUS) for localization of the lesion. The ventral dural tear, frequently occurring in IDH, was managed using a collagen pad, resulting in an uneventful postoperative course without evidence of cerebrospinal fluid (CSF) leak during follow-up. Case Description: We present a 70-year-old female patient with acute back pain, radiating to inner thighs and paraparesis. Magnetic resonance imaging (MRI) showed intervertebral (IV) disc herniation in the L1/2 segment. Subsequent microdiscectomy assisted by IOUS revealed intradurally migrated fragments, which were carefully removed. The ventral dural tear was identified and treated using an absorbable collagen pad. At both 7-week and 18-month follow-up, the patient remained pain-free and showed no new neurological deficits or signs of CSF leakage. Conclusions: Lumbar IDH remains a rare diagnostic challenge, as preoperative imaging is often inconclusive. This case suggests that intraoperative ultrasound may aid localization of intradural pathology, while collagen-pad repair may provide a useful option for managing ventral dural defects when primary closure is technically challenging, although further research is necessary.
Motion-preserving direct osteosynthesis for a C2 complex fracture involving the vertebral body and posterior elements: a case report
Background: Surgical treatment of C2 fractures often involves fixation across C1–2, which restricts atlantoaxial motion. Because the C1–2 segment plays a major role in cervical mobility, motion-preserving strategies may be desirable in selected cases. We report a case of a complex C2 fracture treated with navigation-assisted motion-preserving fixation. Case Description: A 54-year-old man sustained multiple injuries in a motor vehicle collision, including a C2 fracture involving the vertebral body and posterior elements. He presented with neck pain but no neurological deficits. Computed tomography (CT) demonstrated a fracture line extending from the left vertebral body to the right lamina with minimal displacement. CT angiography showed no vertebral artery injury. The patient remained hemodynamically stable. Considering his occupational demands and preference for early return to activity, surgical treatment was performed on hospital day 5. Under intraoperative navigation, direct osteosynthesis was achieved. A lag screw was inserted to reduce and compress the displaced laminar component. Bilateral pars screws connected by a rod were placed to augment stability without crossing adjacent motion segments or performing fusion. The postoperative course was uneventful. The patient was mobilized early with a hard cervical collar and discharged on postoperative day 12. At 13 months, CT confirmed solid bony union. The patient remained symptom-free with preserved cervical range of motion. Conclusions: Motion-preserving fixation using navigation-assisted direct osteosynthesis achieved stable union in a complex C2 fracture involving both anterior and posterior elements. In carefully selected patients, this strategy may serve as a viable alternative to C1–2 fusion.
Considering biomechanical environment in the prevention and treatment of ACDF complications
Erratum: Zero-profile interbody fusion in single and two-level anterior cervical discectomy and fusion: a novel surgical system and its indications