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Background: Over the past decades, spine research has grown substantially, and as the body of literature grows, it is valuable to understand the research landscape. This study aims to examine the geographic origins, author demographics, including the number and gender of authors, and publication output of three prominent spine journals and to assess their scholarly impact.

Methods: A retrospective, bibliometric, cross-sectional analysis was conducted on articles published between 2000 and 2004 (period 1, P1), 2010 and 2014 (period 2, P2), and 2020 and 2024 (period 3, P3) in three spine journals: European Spine Journal (ESJ), Spine, and The Spine Journal (TSJ). Bibliometric data were retrieved using PubMed's Application Programming Interface (API).

Results: Some 14,653 articles underwent analysis. Spine had the highest output in P2 (2946 articles), while TSJ peaked in P3. A marked increase in Asian contributions was observed, with a notable surge in Chinese publications within ESJ; these rose from 4 in P1 to 454 in P3. In the TSJ, the number of articles written by Asian authors increased from 23 to 306. Female first authorship in the ESJ increased from 10.0% to 17.1% and in TSJ, from 5.5% to 14.1%. A notable increase in the average number of authors per publication was observed across all journals. In ESJ, this rose from 4.3 to 7.6; in Spine, from 4.6 to 9.0; and in TSJ, from 4.0 to 8.3.

Conclusions: This study reveals a rise in the number of scientific publications in spine surgery, characterized by an increasing proportion of publications originating from Asia, a higher number of authors per publication, and a growing proportion of female authors. While the progress observed in contributing countries and the increase in gender diversity are promising, disparities persist.

Objective verification of pedicle screw placement on postoperative imaging is essential for patient safety and for evaluating the biomechanical integrity of spinal constructs. Inaccurate screw positioning may compromise stability and increase the risk of neurological injury. Deep learning provides opportunities to automate segmentation of implants and surrounding anatomy, enabling objective and reproducible assessment of implant–anatomy relationships. This study evaluated the feasibility of training readily available convolutional neural networks (CNNs) to segment vertebrae, the spinal canal, and pedicle screws in postoperative thoracolumbar CT images using a limited dataset and 2D slice-based segmentation. One hundred manually annotated axial postoperative CT slices from 20 patients who had undergone posterior fixation were included and divided into training, validation, and test sets across two data splits. Four CNN architectures: YOLOv8, DeepLabv3+, U-net, and Attention U-net, were trained for multi-class segmentation. Model performance was assessed using class-wise Dice Similarity Coefficients (DSC). Across both splits, segmentation accuracy varied by model and anatomical class, mean DSC 0.62–0.90, reflecting variations across classes and models. DeepLabv3+ achieved the highest overall performance, mean DSC 0.83 and 0.78. YOLOv8 demonstrated stable results across splits, particularly for screw segmentation. U-net and Attention U-net performed comparably for spinal canal and screw-head segmentation in the first split but showed reduced performance in the second split. Qualitative assessment confirmed that all models were able to identify key anatomical structures and implants, although metal artifacts affected performance. As a feasibility demonstration, the study showed that DeepLabv3+ and YOLOv8 provided the most consistent results, indicating that robust automated screw–canal assessment is achievable even with limited clinical data.

Purpose: Although complications are known to affect mortality in patients with spinal cord compression (MSCC), the impact of specific complication subtypes on survival and their risk factors remain poorly defined. The aim was to identify risk factors for perioperative and postoperative local and systemic complications in patients who underwent surgery for MSCC and to evaluate their association with postoperative survival.

Methods: We retrospectively analyzed 256 patients who underwent surgical treatment for MSCC between 2003 and 2022. Complications occurring within 30 days postoperatively were classified as perioperative, postoperative local, or postoperative systemic complications. Associations between complications and patient-related variables (age, comorbidities, smoking status, performance status, preoperative ambulatory status, and prior radiotherapy) and surgery-related variables (approach, intraoperative blood loss, and duration of surgery) were examined.

Results: At least one complication occurred in 86 patients (33,6%): 14 perioperative, 39 systemic, and 33 local complications. Postoperative systemic complications (HR 1.8, 95% CI 1.2–2.5; p = 0.003) and lower performance status (HR 1.9, 95% CI 1.4–2.6; p < 0.001), were independently associated with reduced postoperative survival. Impaired preoperative ambulatory function was associated with postoperative complications (HR 2.1, 95% CI 1.0–4.3; p = 0.04).

Conclusion: Postoperative systemic complications were associated with reduced survival following surgery for MSCC. Impaired preoperative ambulatory function increases the risk of complications and should be emphasized in preoperative risk assessment and surgical decision-making.

Introduction: Persistent spinal pain syndrome (PSPS) with predominant low-back pain (LBP) is difficult to manage when conservative and surgical treatments fail. Dorsal root ganglion stimulation (DRG-S) offers segmental, focal neuromodulation that may be particularly suited for managing axial LBP, yet long-term evidence from real-world practice remains limited. This study evaluated the effectiveness, safety, and impact on medication use of bilateral T12 DRG-S in patients with intractable LBP, using prospectively collected registry data.

Methods: Of 33 consecutive patients with chronic LBP assessed for DRG-S, 20 underwent trial stimulation after multidisciplinary evaluation. Eighteen (90%) proceeded to permanent implantation following ≥ 50% pain reduction during trial. Patients were followed via a digital platform at 3, 6, 12, and 24 months. Outcomes included pain intensity (NRS), quality of life (PROMIS-29), pain catastrophizing (PCS), satisfaction, medication use, and adverse events. Statistical comparisons were made between baseline and follow-up time points using paired tests.

Results: Pain intensity decreased substantially and significantly across all follow-up assessments: mean NRS declined from 8.0 ± 1.8 at baseline to 3.6 ± 1.6 at 3 months, 3.2 ± 1.8 at 6 months, 3.6 ± 1.7 at 12 months, and 2.9 ± 1.6 at 24 months (all p < 0.001). At 24 months, 100% of patients achieved ≥ 30% pain reduction and 70% achieved ≥ 50% reduction. Patient-reported outcomes demonstrated broad improvements. PROMIS-29 domains showed significant gains in physical function, pain interference, fatigue, and sleep disturbance, with consistent improvements also observed in anxiety and depression. Pain catastrophizing (PCS) scores decreased markedly, with total scores reduced by 47%–62% across follow-ups (all p < 0.001), reflecting improvements across helplessness, magnification, and rumination subdomains. Medication use declined over time. Mean opioid dose fell from 27 mg/day at baseline to 11.25 mg/day at 1 year and 4.44 mg/day at 2 years (p = 0.019 and 0.011, respectively). Paracetamol use also decreased significantly, whereas gabapentinoid use remained variable. Seven hardware-related complications were recorded (lead migration n = 3, lead fracture/damage n = 4), all successfully managed with revision surgery. Kaplan–Meier analysis estimated mean time to complication at 1080 days. Two patients discontinued therapy (EOT), both for reasons unrelated to device failure.

Conclusions: In this prospective registry, bilateral T12 DRG-S provided durable reduction in pain intensity, improved physical, psychosocial, and cognitive outcomes, and facilitated meaningful opioid-sparing effects over 2 years. Complications were limited to correctable hardware issues, and therapy discontinuation was rare. Although larger multicentre studies are warranted, these findings add important real-world evidence supporting DRG-S as a valuable therapeutic option for refractory axial LBP.

Background: Renal Cell Carcinoma (RCC) represents about 2% of all cancers in Sweden. While RCC is known for its potential to metastasize to the skeleton, few studies have examined the risk factors for pathological fractures and their impact on survival. The Fuhrman grade and AJCC staging systems are commonly used to assess disease aggressiveness, but their relationship to fracture risk and post-fracture outcomes remains unclear.

Methods: This study cross-linked data from the Swedish Fracture Register (SFR) and the Swedish Renal Cancer Register (SNR) to identify RCC patients with pathological fractures. Fracture characteristics, cancer staging (Fuhrman, TNM, AJCC), and histological subtypes were analysed. Survival was estimated using the Kaplan-Meier method.

Results: One hundred four RCC patients (72 men, 32 women) with pathological fractures were included, with clear cell carcinoma being most common (n = 93). Fuhrman grade 3 (n = 34) and fractures in the femur (n = 44) and humerus (n = 37) predominated. Median time from cancer diagnosis to fracture was 11 months. Higher Fuhrman grade, TNM, and AJCC stages were significantly associated with shorter time to fracture (p < 0.001). The median overall survival was 31 months and was related to Fuhrman grade (p = 0.013) and AJCC stage (p < 0.001). The median survival post-fracture was 8 months, with no significant association with cancer grade or stage.

Conclusion: Advanced Fuhrman grade and AJCC stage predict faster progression to pathological fractures in RCC. Given the poor prognosis after pathological fractures, early risk stratification and individualized treatment approaches are essential to improve outcomes.

Background: subperception (paresthesia-free) dorsal root ganglion (DRG) stimulation is increasingly used for focal neuropathic pain, but sham-controlled evidence remains limited. We conducted a randomized, double-blind, sham-controlled crossover trial with enriched enrollment design in established DRG-stimulation responders.

Methods: In this single-center trial, adults with chronic peripheral neuropathic or nociplastic pain with implanted DRG system and sustained response (≥50% pain reduction for ≥3 months on stable stimulation settings and medication) were randomized 1:1 to active→sham or sham→active stimulation. Participants completed two 5-day treatment periods separated by a 24-hour washout with stimulation off. Active stimulation was delivered at 90% of the perception threshold, and sham was stimulation off. The primary outcome was median pain intensity on a 0–10 Numeric Rating Scale (NRS). Secondary outcomes included patient satisfaction and Patient Global Impression of Change (PGIC) domains. Analyses used Wilcoxon signed-rank tests with Hodges-Lehmann estimates.

Results: In 20 randomized patients, pain intensity was lower during active than sham stimulation (median NRS 3.0 (IQR 2.0–4.0) vs 6.0 (IQR 4.0–7.0); Hodges-Lehmann median difference, −2.5; 95% CI −3.0 to −2.0; p<0.001). Patient satisfaction and all PGIC domains favored active stimulation. Two participants terminated one treatment period early per prespecified criteria; available data were retained. No serious or device-related adverse events were reported.

This nationwide register-based cohort study examined the association between castration status and postoperative survival in men who had undergone surgery for spinal metastases from prostate cancer. Bone metastases are common in prostate cancer, with the spine being the most frequent site. Using data from the Swedish Spine Register (Swespine) and Prostate Cancer Database Sweden (PCBaSe), 306 men with prostate cancer who underwent spinal surgery were identified. In total, 81 were categorized as castration-sensitive and 225 as castration-resistant disease at the time of spinal surgery. Postoperative survival was estimated using Kaplan-Meier analysis and compared with the log-rank test. Multivariable Cox regression was used to adjust for potential confounders. Median survival after surgery was significantly longer in men with castration-sensitive prostate cancer (33 months, IQR 15-55) compared to those with castration-resistant disease (8 months, IQR 5-31; p < 0.001). Castration-sensitive status was independently associated with a lower risk of death (hazard ratio 0.29, 95% CI: 0.20-0.41). These findings indicate that castration sensitivity is a strong prognostic factor for survival after surgery for spinal metastases from prostate cancer and should be considered in surgical decision-making.

Study Design: Retrospective cohort study.

Objective: Spinal metastases are common in patients with breast cancer, and accurate estimation of postoperative survival is crucial for selecting appropriate candidates for metastasis surgery. This study investigated the association between breast cancer subtype, according to the St. Gallen classification, and survival after surgery for spinal metastases with the aim of improving prognostic assessment and supporting informed patient counselling.

Methods:: This study included 110 patients with breast cancer who underwent surgery for spinal metastases identified from the Swedish Spine Register and the Swedish National Quality Register of Breast Cancer. Patients were categorized in terms of the breast cancer subtype according to the St. Gallen classification. Postoperative survival was analysed using Kaplan-Meier estimates and a Cox proportional hazards model.

Results: The overall median survival following spinal surgery was 25 months (95% CI 19-31), while the median postoperative survival by subtype was 39 months (95% CI 28-50) for luminal A patients, 20 months (95% CI 9-31) for luminal B patients, and 48 months (95% CI 20-76) for luminal B/HER2+ patients. The median survival was not reached for the nonluminal HER2+ group, whereas patients with triple-negative breast cancer had a median survival of only 5 months (95% CI 4-6). The St. Gallen subtype was significantly associated with postoperative survival according to univariable (P<0.001) and multivariable analyses (P = 0.011).

Conclusions: Breast cancer subtype according to the St. Gallen classification was significantly associated with survival after surgery for spinal metastases. These findings indicate that the St. Gallen classification may serve as a valuable prognostic tool in the metastatic spine setting. Incorporation of molecular subtype information may improve estimation of postoperative survival and support informed patient counselling, expectation management, and individualized surgical decision-making in patients with breast cancer spinal metastases.

Purpose: Spinal metastasis as the first manifestation of lung cancer, presents challenges in diagnosis, prognosis, and treatment planning. This study aims to evaluate postoperative survival outcomes and to identify prognostic factors in treatment-naïve patients undergoing surgery for spinal metastases, focusing on clinical and molecular variables.

Methods: This retrospective cohort study included 149 patients who underwent surgery for spinal metastases from lung cancer between 2011 and 2023. Data were obtained from the Swedish National Register for Spine Surgery (Swespine) and the Swedish National Lung Cancer Register (SNLCR). Patients were grouped based on whether spinal metastasis was the initial manifestation of lung cancer or occurred during known disease. Kaplan–Meier analysis and Cox proportional hazards models were used to assess postoperative survival and prognostic factors.

Results: Of the 149 patients, 114 (77%) presented with spinal metastasis as the initial sign of lung cancer. Median survival in this group was 6 months, compared to 3 months in patients with a prior confirmed lung cancer diagnosis (p = 0.022). In the initial presentation group, longer survival after surgery was observed in patients with predictive biomarkers (8 vs. 5 months, p = 0.003), preserved ambulatory function (8 vs. 3 months, p = 0.002), and better WHO performance status (p < 0.001). In multivariable analysis, biomarker status, WHO performance status, ambulatory function, and age were independently associated with post-operative survival.

Conclusion: Patients undergoing surgery for spinal metastases as the initial manifestation of lung cancer form a distinct subgroup. Early functional and molecular assessment may improve patient selection and surgical outcome in this population.

INTRODUCTION: Pain, comprising sensory and emotional elements, is influenced by pain catastrophizing, which magnifies pain and promotes helplessness and rumination. This study explores the relationship between pain catastrophizing and outcomes following selective nerve root blockade (SNRB) in patients with lumbar radicular pain (LRP).

METHODS: A prospective cohort study of 103 LRP patients, confirmed by MRI, was conducted. All participants underwent SNRB at Umeå University Hospital. Outcomes were measured using PROMIS-29 and the Pain Catastrophizing Scale (PCS) at baseline and several intervals up to 84 days post-intervention. Patients were categorized into responder (≥30% pain reduction) and non-responder groups and stratified into three groups based on baseline PCS scores. Changes in outcomes from baseline to 14 days post-SNRB were analyzed in relation to PCS groups. PCS changes over time were evaluated between responders and non-responders. Statistical analyses assessed PCS and outcome changes.

RESULTS: Baseline pain catastrophizing was not a significant predictor of pain response to SNRB. However, responders demonstrated significant reductions in pain catastrophizing following the intervention, suggesting that SNRB may influence cognitive coping mechanisms related to pain.

CONCLUSION: SNRB reduces pain catastrophizing in LRP patients, although baseline catastrophizing does not predict pain outcomes. Addressing catastrophizing remains important but may serve better as an outcome measure rather than a predictor of treatment response.