Citations

Abstract Background Native vertebral osteomyelitis (NVO) is a life-threatening spinal infection with rising incidence and significant morbidity. Despite its growing burden, long-term data on clinical characteristics, management trends, and outcomes remain limited. Methods We conducted a 26-year multicenter retrospective cohort study of adults (≥18 years) diagnosed with NVO at Mayo Clinic sites between 1999 and 2024. Demographic, microbiologic, treatment, and outcome data were analyzed across five time periods. Predictors of treatment failure were assessed using a multivariable competing risk model. Results Among 1255 patients (median age 67; 66% male), lumbosacral involvement was most common (65%), and 21% had multilevel involvement. Pathogens were identified in 77%, most commonly Staphylococcus aureus (49%; Methicillin-susceptible S. aureus 37%, methicillin-resistant S. aureus 13%). Over time from 1999–2004 to 2020–2024, Gram-negative bacilli increased from 6% to 14% (P = .048). Comorbidities including chronic kidney disease (10% to 21%), active chemotherapy (6% to 11%), and immunosuppression (8% to 17%) increased significantly. Additionally, 1-year treatment failure declined (16% to 10%). In multivariable analysis, diabetes mellitus (subdistribution hazard ratio [sHR] 1.92, 95% CI 1.18–3.13) and multilevel involvement (sHR 1.67, 95% CI 1.17–2.38) were associated with increased incidence of treatment failure, while concurrent infections (sHR 0.57, 95% CI 0.37–0.87) and higher Charlson Comorbidity Index (sHR 0.62, 95% CI 0.43–0.90) were associated with lower failure. Conclusions This large multicenter cohort highlights increasing host complexity, shifting microbiology, and predictors of failure, emphasizing the importance of early risk stratification and tailored strategies, such as multidisciplinary evaluation and close follow-up of high-risk patients to improve outcomes.

Background: Scoliosis has various etiologies, ranging from idiopathic, congenital, to those with spinal cord abnormalities. Advanced imaging is not always feasible and limited by cost, low-yield, and anesthesia risks in children. Given artificial intelligence's potential, we hypothesize that a deep learning (DL)–based image classifier will demonstrate superior performance in radiographic classification of scoliosis etiology compared witht experienced spine surgeons based on spine radiographs. Methods: One thousand thirty-six pediatric patients from single institution with scoliosis diagnosis and paired anterior-posterior - lateral images were included. Patients were manually classified based on their scoliosis etiology from chart review, including previous spine imaging studies when available. Categories included idiopathic, congenital, and spinal cord pathology. Images were randomized and assigned for training, validation, and testing. A DL-classifier using EfficientNet B4 architecture was trained on the radiographs. Accuracy and positive predictive value as defined by precision, recall, and F1-score were calculated to assess final performance metrics. Results: The trained classifier performed well at identifying correct etiologies, with F1-Score (harmonic mean of precision-recall) of 0.97. Model precision was 0.99 for adolescent idiopathic scoliosis, 0.89 for congenital, and 0.78 for spinal cord pathology. Performance was higher on more common classes, with lower performance observed in class with fewer images. The algorithm has highest overall precision (0.96), recall (0.96), and F1 (0.96), while Surgeons 1 and 2 have lower accuracies (precision 0.80, recall 0.79, and F1 0.79 and precision 0.76, recall 0.67, and F10.71, respectively). There was no clear pattern identified regarding the surgeons' errors and poor agreement on which X-rays corresponded to underlying spinal cord pathology. Conclusion: A DL-convolutional-neural-network classifier has been trained to high degree of accuracy to distinguish between 3 scoliosis etiologies on pediatric spine radiographs. This model could provide a novel tool to clinicians to decide when to refer for axial imaging. It had superior diagnostic performance compared with experienced spine surgeons. After further validation and refinement, a clinician could put a patient's X-rays into the predictive tool for analysis and use the results to discuss with the family the risk of finding spinal cord pathology, helping them determine together the best timing for an MRI. Level of Evidence: Level III . See Instructions for Authors for a complete description of levels of evidence.

Background/Objectives: Accurate assessment of spinal bone density is essential for evaluating bone health, particularly in preoperative planning. Conventional manual methods for Hounsfield unit (HU) measurements rely on single-slice measurements within the region of interest, limiting their precision and reproducibility in patients with severe vertebral deformities. We hypothesize that a novel deep-reasoning and learning model (DR-AI) can fully automate spinal bone density assessment volumetrically, with high correlations to spinal bone mineral density (BMD) obtained from dual-energy X-ray absorptiometry (DXA), as well as to the T- and Z-scores. Methods: A cross-sectional study was conducted on patients who had BMD assessment of their lumbar spine and lumbar CT scans within 1 year. The fully-automated DR model was utilized to analyze the soft-tissue window of the lumbar vertebrae CT scans. Spearman correlation coefficients were calculated to assess the strength of relationships between the computed volumetric HUs and the BMD, T-, and Z-scores from each vertebra. Results: 84 patients (67 females, mean age 74.1 ± 10.3 years; 17 males, mean age 68.1 ± 12.4 years) meeting inclusion criteria. Correlation analyses for L1 to L4 showed significant positive relationships (p < 0.0001), with the strongest correlation at L2 between HU and BMD (ρ = 0.75). Conclusions: the DR model for automated assessment of volumetric HUs offers a highly reliable, efficient, and precise alternative to DXA measurements.

Study design. Retrospective observational study of consecutive patients. Objective. The purpose of the study is to determine if a surgeon’s qualitative assessment of bone intraoperatively correlates with radiologic parameters of bone strength. Summary of Background Data. Preoperative radiologic assessment of bone can include modalities such as computed tomography (CT) Hounsfield units (HUs), dual-energy x-ray absorptiometry (DXA) bone mineral density with trabecular bone score (TBS) and magnetic resonance imaging vertebral bone quality (VBQ). Quantitative analysis of bone with screw insertional torque and pull-out strength measurement has been performed in cadaveric models and has been correlated to these radiologic parameters. However, these quantitative measurements are not routinely available for use in surgery. Surgeons anecdotally judge bone strength, but the fidelity of the intraoperative judgment has not been investigated. Methods. All adult patients undergoing instrumented posterior thoracolumbar spine fusion by one of seven surgeons at a single center over a 3-month period were included. Surgeons evaluated the strength of bone based on intraoperative feedback and graded each patient’s bone on a 5-point Likert scale. Two independent reviewers measured preoperative CT HUs and magnetic resonance imaging VBQ. Bone mineral density, lowest T-score, and TBS were extracted from DXA within 2 years of surgery. Results. Eighty-nine patients were enrolled and 16, 28, 31, 13, and 1 patients had Likert grade 1 (strongest bone), 2, 3, 4, and 5 (weakest bone), respectively. The surgeon assessment of bone correlated with VBQ (τ=0.15, P=0.07), CT HU (τ=−0.31, P<0.01), lowest DXA T-score (τ=−0.47, P<0.01), and TBS (τ=−0.23, P=0.06). Conclusion. Spine surgeons’ qualitative intraoperative assessment of bone correlates with preoperative radiologic parameters, particularly in posterior thoracolumbar surgeries. This information is valuable to surgeons as this supports the idea that decisions based on feel in surgery have a statistical foundation.

Abstract Background Cutibacterium acnes can cause spinal implant infections. However, little is known about the optimal medical management and outcomes of C. acnes spinal implant infections (CSII). Our study aims to describe the management of patients with CSII and evaluate the clinical outcomes. Methods We performed a retrospective cohort study of patients aged 18 years or older who underwent spinal fusion surgery with instrumentation between January 1, 2011, and December 31, 2020, and whose intraoperative cultures were positive for C. acnes. The primary outcome was treatment failure based on subsequent recurrence, infection with another organism, or unplanned surgery secondary to infection. Results There were 55 patients with a median follow-up (interquartile range) of 2 (1.2–2.0) years. Overall, there were 6 treatment failures over 85.8 total person-years, for an annual rate of 7.0% (95% CI, 2.6%–15.2%). Systemic antibiotic treatment was given to 74.5% (n = 41) of patients for a median duration of 352 days. In the subgroup treated with systemic antibiotics, there were 4 treatment failures (annual rate, 6.3%; 95% CI, 1.7%–16.2%), all of which occurred while on antibiotic therapy. Two failures occurred in the subgroup without antibiotic treatment (annual rate, 8.8%; 95% CI, 1.1%–31.8%). Conclusions Our study found that the estimated annual treatment failure rate was slightly higher among patients who did not receive antibiotics. Of the 6 failures observed, 4 had recurrence of C. acnes either on initial or subsequent treatment failures. More studies are warranted to determine the optimal duration of therapy for CSII.

Operating room throughput variability with spinal procedures revealed task inefficiency and potential safety concerns. Using the DMAIC framework (Define, Measure, Analyze, Improve, Control), a transdisciplinary team conducted a quality improvement (QI) research project to identify and address safety concerns with prone patient positioning. The main problem with patient positioning was undefined standard practice. Clinicians reported prone patient positioning for spinal surgery patients is physically demanding. Thus, the team conducted a rapid upper limb assessment for injury risk during patient positioning and identified a greater risk of clinician injury in the manual transfer process. The QI research team recommended the mechanical process of rotating patients with the Jackson Table to improve workload for the Surgical Team and developed training and design enhancements to support this workflow. The DMAIC quality framework enabled clinician collaboration with researchers to develop interventions to support a standardized process during prone patient positioning with the Jackson Table.

Study Design: Retrospective case series. Objective: Sacral insufficiency fracture is a rare and serious complication following lumbar spine instrumented fusion. The purpose of this study was to describe the patient characteristics, presentation, evaluation, treatment options, and outcomes for patients with sacral insufficiency fracture after short-segment lumbosacral fusion. Methods: Six patients from our institutional database and 16 patients from literature review were identified with a sacral insufficiency fracture after short-segment (L4-S1 or L5-S1) lumbar fusion within 1 year of surgery. Results: Patients were 55% female with a mean age of 58 years and body mass index of 30 kg/m 2 . Osteoporosis or osteopenia was the most common comorbidity (85%). Half of patients sustained a sacral fracture after surgery from a posterior approach, while the others had anterior or anterior-posterior surgery. Mean time to fracture was 42 days with patients clinically presenting with new sacral pain (86%), radiculopathy (60%), or neurologic deficit (5%). Ultimately, 73% of patients underwent operative fixation often involving extension of the construct (75%) and fusion to the pelvis (69%). Men ( P = .02) and patients with new radicular pain or neurologic deficit ( P = .01) were more likely to undergo revision surgical treatment while women over 50 years of age were more likely to be treated conservatively ( P = .003). Conclusions: Spine surgeons should monitor for sacral insufficiency fracture as a source of new-onset pain in the postoperative period in patients with a short segment fusion to the sacrum. The recognition of this complication should prompt an assessment of bone health and management of underlying bone fragility.

Mini We compared the sensitivity and specificity of peri-implant tissue culture to the vortexing–sonication technique for the diagnosis of spinal implant infection (SII). Lower thresholds of sonicate fluid culture positivity showed increased sensitivity with maintained specificity. We recommend a threshold of 20 CFU/10 mL for sonicate culture positivity for the diagnosis of SII. Study Design. This is a retrospective study comparing the diagnosis of spinal implant infection (SII) by peri-implant tissue culture to vortexing–sonication of retrieved spinal implants. Objective. We hypothesized that vortexing–sonication would be more sensitive than peri-implant tissue culture. Summary of Background Data. We previously showed implant vortexing–sonication followed by culture to be more sensitive than standard peri-implant tissue culture for diagnosing of SII. In this follow-up study, we analyzed the largest sample size available in the literature to compare these two culture methods and evaluated thresholds for positivity for sonicate fluid for SII diagnosis. Methods. We compared peri-implant tissue culture to the vortexing–sonication technique which samples bacterial biofilm on the surface of retrieved spinal implants. We evaluated different thresholds for sonicate fluid positivity and assessed the sensitivity and specificity of the two culture methods for the diagnosis of SII. Results. A total of 152 patients were studied. With more than 100 colony forming units (CFU)/10 mL as a threshold for sonicate fluid culture positivity, there were 46 patients with SII. The sensitivities of peri-implant tissue and sonicate fluid culture were 65.2% and 79.6%; the specificities were 88.7% and 93.4%, respectively. With more than 50 CFU/10 mL as a threshold, there were 50 patients with SII. The sensitivities of peri-implant tissue and sonicate fluid culture were 68.0% and 76.0%; the specificities were 92.2% for both methods. Finally, with more than or equal to 20 CFU/10 mL as a threshold, there were 52 patients with SII. The sensitivities of peri-implant tissue and sonicate fluid culture were 69.2% and 82.7%; the specificities were 94.0% and 92.0%, respectively. Conclusion. Implant sonication followed by culture is a sensitive and specific method for the diagnosis of SII. Lower thresholds for defining sonicate fluid culture positivity allow for increased sensitivity with a minimal decrease in specificity, enhancing the clinical utility of implant sonication. Level of Evidence: 4

Study Design. Retrospective matched cohort study. Objective. To determine if low-pressure lumbar provocation discography (PD) results in long-term accelerated disc degeneration, internal disc disruption, or disc herniation in patients with symptomatic low back pain (LBP). Summary of Background Data. Study of subjects without clinically-significant LBP suggests that high-pressure PD may accelerate disc degeneration. Methods. Consecutive patients with symptomatic LBP who underwent magnetic resonance imaging (MRI), PD, and repeat MRI more than 7 years later, but did not undergo subsequent spinal fusion surgery, were included. Punctured discs were matched (1:2 to 1:4) to corresponding discs in a control cohort by age, BMI, Pfirrmann score (±2), and presence of disc herniation; control cohort inclusion required MRIs for symptomatic LBP, separated by more than 7 years. The primary outcome of the study was a progression in Pfirrmann score category (I–II, III–IV, V). MRI disc-to-CSF T2 signal-intensity ratio, disc height, disc herniations, high intensity zones (HIZs), and Modic changes were assessed. Results. Baseline and follow-up MRIs were available for 77 discs exposed to PD, and for 260 discs in the matched control cohort. There was no difference in the proportion of punctured discs that advanced in Pfirrmann score category in the PD group (17%, 95% CI 9–27%) compared with corresponding discs in the Control group (21%, 95% CI 17–27%), P = 0.3578, or in non-punctured discs in the PD group (35%, 95% CI 21–51%) compared with corresponding discs in the Control group (34%, 95% CI 27–42%), P = 0.1169. There were no differences in disc-to-CSF T2 signal-intensity ratio, presence of disc herniations, HIZs, or Modic changes following puncture in the PD versus matched cohort discs or in the non-punctured PD cohort discs versus corresponding control cohort discs (P > 0.05). Conclusion. Patients with symptomatic LBP who underwent low-pressure PD, but who did not undergo a subsequent spinal fusion surgery, developed disc degeneration and new disc herniations at a similar rate to corresponding discs in matched control patients. Level of Evidence: 3