Search Results (48)

This work presents an original implementation of the digital sampling pipeline for spaceborne Fourier Transform Spectrometers (FTSs). The implementation aims at improving the robustness of the spectrometer to harsh environmental conditions, including mechanical vibrations and a wide operational temperature range, avoiding the use of dedicated electronic hardware for the interferometer mirrors’ speed control and interferogram sampling. The FTS configuration is based on the constant time step sampling of the interferometer using a standard ADC (Analogue to Digital Converter), along with two metrology laser channels. The development tool is a MATLAB-based simulator developed to emulate the FTS and, in particular, the generation and acquisition of interferograms, incorporating harmonic vibrations and detector noise. The simulator was exploited to compare state-of-the-art techniques and newly implemented variants. An improvement of the arccosine method is first proposed, revising the normalisation process to exploit the full set of recorded data without discarding critical points. Subsequently, methods using two reference channels have been developed and evaluated. Two implementations are considered: two references at the same wavelength with an optimised phase shift (i.e., π/2) and two references at different wavelengths. Different data fusion strategies are compared in terms of spectral uncertainty, varying types of simulated disturbances and noise amplitudes. Results show that the optimal combination of two same-wavelength references consistently outperforms any other configuration, yielding lower average spectral errors and more stable performance over the frequency range and for a lower SNR of reference channels. Conversely, dual-wavelength strategies exhibit reduced accuracy, though they offer flexibility when fixed phase shifts cannot be maintained. The optimal combination of two same-wavelength reference channels, phase-shifted, is a promising configuration for spaceborne FTSs, so the development and test of an instrument breadboard is envisaged as the consequent development of this work. Full article

Background: Anterior Lumbar Interbody and Fusion (ALIF) is particularly effective for improving radiographic alignment and functional outcomes. However, it also introduces distinct technical challenges, even for surgeons who are highly experienced with other lumbar fusion approaches. This study analyzes the effect of surgeon experience on clinical outcomes, radiographic parameters, and operative metrics in patients with degenerative lumbar disc disease undergoing single-level L5-S1 anterior lumbar interbody fusion. Methods: Adult patients who underwent L5-S1 ALIF with or without posterior fixation for degenerative disc disease between June 2017 and December 2024 were included. Patients were stratified into Early (from 2017 to December 2020), Middle (January 2021 to December 2022), and Recent (January 2023 to December 2024) groups. Demographics, radiographic alignment, in-hospital outcomes, and 2-year complication and reoperation rates were compared based on time of surgery. Multivariate logistic and linear regression adjusted for age, sex, BMI, comorbidities, prior fusion, and posterior instrumentation was conducted to assess the effect of accumulation of surgeon experience. Results: A total of 203 ALIFs were performed (mean age: 57.6 years; 50.7% female; mean Charlson Comorbidity Index: 2.1). Recent cases showed greater PT reduction (Early = 0.9°, Middle = −1.5°, Recent = −2.2°, p = 0.039), improved PI-LL mismatch correction (−0.4°, −4.8°, −5.4°, p = 0.007), higher L5-S1 lordotic correction (6.7°, 8.4°, 11.4°, p = 0.003), lower estimated blood loss (21.9 mL, 13.8 mL, 10.0 mL, p = 0.006), shorter OR time (107.4 min, 86.6 min, 75.2 min, p < 0.001), and fewer mechanical complications (39.3% vs. 13.7%, p < 0.001) and reoperations (10.7% vs. 2.1%, p = 0.023). Regression showed that each additional year of experience predicted improved alignment, lower blood loss and OR time, and reduced odds of complications (OR = 0.54, p < 0.001) and reoperations (OR = 0.49, p = 0.015). Conclusions: In this single-surgeon, single-center cohort, increasing ALIF-specific experience over time was associated with improvements in sagittal alignment, operative efficiency, and lower complication and reoperation rates. These findings describe the longitudinal learning curve of one surgeon and should be interpreted within this context. Full article

Recent advances in deep learning (DL) have enabled the integration of diverse biomedical data for disease prediction and risk stratification. Building on this progress, the overall objective of this study was to develop and evaluate a multimodal DL framework for robust multi-label classification (MLC) of major comorbidities in patients with obstructive sleep apnea (OSA) using physiological time series signals and clinical data. This study proposes a robust framework for multi-label classification (MLC) of comorbidities in patients with OSA using diverse physiological and clinical data sources. We conducted a retrospective observational study including a convenience sample of 144 patients referred for overnight polysomnography at the Sleep Medicine Center (SleepLab Split), University Hospital Centre Split (KBC Split), Split, Croatia. Patients were selected based on predefined inclusion criteria and data availability. A one-dimensional Convolutional Neural Network (1D-CNN) was developed to process and fuse time series signals, oxygen saturation ($Sp{O}_2$), derived $Sp{O}_2$ features, and nasal airflow (FP0), with demographic and physiological parameters, enabling the identification of key comorbidities such as arterial hypertension, diabetes mellitus, and asthma/COPD. The instruments included polysomnography-derived signals (SpO₂ and FP0 airflow) and structured demographic/physiological parameters. Signals were preprocessed and used as inputs to the proposed fusion model. The proposed model was trained and fine-tuned using the Optuna hyperparameter optimization framework, addressing class imbalance through weighted loss adjustments. Its performance was comprehensively assessed using multi-label evaluation metrics, including macro/micro F1-score, AUC-ROC, AUC-PR, subset and partial accuracy, Hamming loss, and multi-label confusion matrix (MLCM). The study protocol was approved by the Ethics Committee of the School of Medicine, University of Split (Approval No. 003-08/23-03/0015, Date: 17 October 2023). The 1D-CNN achieved superior predictive performance compared to traditional machine learning (ML) classifiers with macro AUC-ROC = 0.731 and AUC-PR = 0.750. The model demonstrated consistent behavior across age, gender, and BMI groups, indicating strong generalization and minimal demographic bias. In conclusion, the results confirm that $Sp{O}_2$ and airflow signals inherently encode comorbidity-specific physiological patterns, enabling efficient and scalable screening of OSA-related comorbidities without the need for full polysomnography. Although the study is limited by data set size, it provides a methodological basis for the application of multi-label DL models in clinical decision support systems. Future research should focus on the expansion of multi-center datasets, thereby improving model interpretability and potential clinical adoption. Full article

Background/Objectives: Following lumbar fusion procedures, adjacent segment degeneration (ASD) at cranial levels presents as a well-documented long-term complication, manifesting through recurrent pain, neurological deficits, and progressive functional decline. The prone single-position technique for lateral lumbar interbody fusion (PSP-LLIF) streamlines surgical workflow by eliminating the need for intraoperative patient repositioning; however, comprehensive evidence supporting its clinical and radiological effectiveness in managing cranial ASD remains insufficient. Material and Methods: This retrospective cohort study examined 30 consecutive patients presenting with symptomatic cranial adjacent segment disease who were treated with PSP-LLIF at a single institution. Patient-reported outcome measures included visual analog scale (VAS) assessments for axial and radicular pain, alongside the Oswestry Disability Index (ODI) for functional status evaluation. Radiological parameters included overall and segmental lumbar lordotic measurements, anterior and posterior disk height, fusion status, and instrumentation-related complications. Results: At 12-month postoperative evaluation, substantial clinical improvements were demonstrated. Mean VAS reductions measured 4.7 points for axial pain and 6.5 points for radicular pain, while ODI decreased by 28.5 points (p < 0.05). Radiological assessment demonstrated mean increases of 6.3° in lumbar lordosis and 5.1° in segmental lordosis, along with significant gains in both anterior and posterior disk height (p < 0.05). Solid fusion was radiographically confirmed at all instrumented levels. Temporary postoperative neurological symptoms developed in several patients but resolved spontaneously without requiring revision surgery. Conclusions: PSP-LLIF yields substantial clinical benefit and reliable radiological correction in patients with symptomatic cranial ASD. Optimal outcomes necessitate rigorous adherence to position-specific technical modifications, particularly maintenance of perpendicular fluoroscopic trajectories and implementation of continuous neural monitoring to account for prone-induced anatomical shifts. This approach represents a viable treatment strategy for patients with symptomatic cranial ASD. Full article

Background: Neurofibromatosis 1 is an autosomal dominant disorder accompanied by extensive early-onset spinal manifestations, with or without dystrophic scoliotic features. While non-dystrophic subtypes can often be treated similarly to idiopathic scoliosis, dystrophic scoliosis typically requires more aggressive intervention, often involving instrumentation in severely compromised pedicles or vertebrae. Purpose: This review aims to present recent advances in the surgical treatment of Neurofibromatosis 1-associated scoliosis, including surgical techniques and emerging guidance methods. Methods: An electronic literature search was conducted in Web of Science and PubMed to identify surgical techniques for scoliosis in patients with Neurofibromatosis 1. Results: Forty-one studies on the operative treatment of dystrophic scoliosis or both subtypes were retrieved. Although aggressive treatment with combined anterior and posterior fusion are widely used, posterior-only methods, which avoid plexiform tumours, present encouraging results. Recent studies highlight the effectiveness of growing rod systems in early-onset cases, enabling delayed fusion while preserving T1-S1 growth. Promising results from sectional or segmented correction techniques demonstrate better sagittal balance and Cobb angle correction, respectively. Preoperative use of halo-gravity traction, which has been extensively studied, is associated with reduced neurological impairment and encourages better correction results, avoiding autofusion. Various studies have also reported more precise pedicle screw placement with guidance of O-arm and triggered electromyography (t-EMG). Conclusions: The correction of spinal scoliotic deformities presents a significant challenge. However, recent advances in surgical techniques and intraoperative guidance offer promising strategies for more effective management. Full article

Background: Accurate deformity classification and fusion-level planning are essential in adolescent idiopathic scoliosis (AIS) surgery and are traditionally guided by Cobb angle measurement and the Lenke system. Multimodal large language models (LLMs) (e.g., ChatGPT-4.0; Claude 3.7 Sonnet, Gemini 2.5 Pro, DeepSeek-R1-0528 Chat) are increasingly used for image interpretation despite limited validation for radiographic decision-making. This study evaluated the agreement and reproducibility of contemporary multimodal LLMs for AIS assessment compared with expert spine surgeons. Methods: This single-center retrospective study included 125 AIS patients (94 females, 31 males; mean age 14.8 ± 1.9 years) who underwent posterior instrumentation (2020–2024). Two experienced spine surgeons independently performed Lenke classification (including lumbar and sagittal modifiers) and selected fusion levels (UIV–LIV) on standing AP, lateral, and side-bending radiographs; discrepancies were resolved by consensus to establish the reference standard. The same radiographs were analyzed by four paid multimodal LLMs using standardized zero-shot prompts. Because LLMs showed inconsistent end-vertebra selection, LLM-derived Cobb angles lacked a common anatomical reference frame and were excluded from quantitative analysis. Agreement with expert consensus and test–retest reproducibility (repeat analyses one week apart) were assessed using Cohen’s κ. Evaluation times were recorded. Results: Surgeon agreement was high for Lenke classification (92.0%, κ = 0.913) and fusion-level selection (88.8%, κ = 0.879). All LLMs demonstrated chance-level test–retest reproducibility and very low agreement with expert consensus (Lenke: 1.6–10.2%, κ = 0.001–0.036; fusion: 0.8–12.0%, κ = 0.003–0.053). Claude produced missing outputs in 17 Lenke and 29 fusion-level cases. Although LLMs completed assessments far faster than surgeons (seconds vs. ~11–12 min), speed did not translate into clinically acceptable reliability. Conclusions: Current general-purpose multimodal LLMs do not provide reliable Lenke classification or fusion-level planning in AIS. Their poor agreement with expert surgeons and marked internal inconsistency indicate that LLM-generated interpretations should not be used for surgical decision-making or patient self-assessment without task-specific validation. Full article

Background: Primary cervical spine infection is a rare but rapidly progressive disease that can cause early neurological damage, leading to increased morbidity and mortality. Despite its rising incidence, optimal treatment remains controversial. This study compared clinical, hematological, microbiological, and radiological outcomes among such patients treated with different methods. Methods: This retrospective comparative study is a secondary analysis of a previously reported cohort of 59 patients with primary cervical spine infection between 1992 and 2018 at a single institution. Patients were stratified into conservative (Group C, n = 14), surgery with instrumentation (Group S + I, n = 32), and surgery without instrumentation (Group S, n = 13) groups. Outcome measures included neurological status, antibiotic duration, hematological markers, radiological parameters (segmental angle, C2–C7 angle, segmental height, fusion rate), and complications. Results: The mean age and follow-up period were 61.4 years and 19.4 months, respectively. Group S + I demonstrated significantly better neurological outcomes at the last follow-up (p = 0.047) and shorter antibiotic treatment duration (p < 0.001). Radiological outcomes were superior in Group S + I, with greater improvements in segmental angle (p < 0.001), C2-C7 angle (p < 0.001), mean segmental height (p < 0.001), and fusion rate (84.4% vs. 14.3% and 46.2% in Group C and Group S, respectively; p < 0.001). Group S had significantly higher complication (46.2%, p = 0.011) and mortality (30.8%, p = 0.001). Hematological and microbiological results were not significantly different among groups. Conclusions: Surgical debridement with anterior instrumentation provided superior outcomes compared with conservative treatment or surgery without instrumentation. Early surgery with appropriate stabilization should be considered to optimize prognosis and minimize complications. Full article

Background/Objectives: Spinal fusion with static fixation—surgically joining two or more vertebrae to eliminate motion—is commonly employed to treat degenerative spinal disease. However, the rigidity imposed by static constructs and the increased load on the adjacent segments frequently result in complications such as disc or facet degeneration, spinal stenosis (SS), and segmental instability. This study investigates the effectiveness of pedicle-based dynamic stabilization using the Dynesys system, particularly in a dynamic-transitional optima (DTO) hybrid configuration, in mitigating adjacent segment disease (ASD) and improving clinical outcomes. In this work, we analyzed the mechanical performance and intermediate-term clinical effects of the DTO hybrid lumbar device, focusing on how the load-sharing properties of the Dynesys cord–spacer stabilizers may contribute to junctional complications in individuals with diverse grades of intervertebral disc degeneration. Study Design/Setting: We designed a combined biomechanical finite element (FE) and experimental analysis to predict the clinical outcomes. Patient Sample: Among 115 patients with lumbar SS enrolled for analysis, 31 patients (mean age: 68.5 ± 7.5 years), with or without grade I spondylolisthesis (18/13), underwent a two-level DTO hybrid procedure—L4–L5 static fixation and L3–L4 dynamic stabilization—with minimal decompression to preserve the posterior tension band. Post-surgical follow-ups were conducted for over 48 months (range: 49–82). Outcome Measures: Radiological assessments were performed by two neurosurgeons, one orthopedic surgeon, and one neuroradiologist. The posterior disc height, listhesis distance, and dynamic angular changes were measured pre- and postoperatively to evaluate ASD progression. Methods: Dynamic instrumentation was assigned to the L3–L4 motion segment with lesser disc deterioration, in contrast to the L4–L5 segment, where static fixation was applied due to its greater degree of degeneration. FE analysis was performed under displacement-controlled conditions. Intersegmental motion analysis was conducted under load-controlled conditions in a synthetic model. Results: The DTO hybrid devices reduced stress and motion at the transition segment. However, compensatory biomechanical effects were more pronounced at the adjacent cephalad than the caudal segments. In the biomechanical trade-off zone—where balance between motion preservation and stabilization is critical—the flexible Dynesys cord significantly mitigated stiffness-related issues during flexion. At the L3–L4 transition level, the cord–spacer configuration enhanced dynamic function, increasing motion by 2.7% (rotation) and 12.7% (flexion), reducing disc stress by 4.1% (flexion) and 12.9% (extension), and decreasing the facet contact forces by 4.9% (rotation) and 15.6% (extension). The optimal cord stiffness (50–200 N/mm) aligned with the demands of mild disc degeneration, whereas stiffer cords were more effective for segments with higher degeneration. The pedicle screw motion in dynamic Dynesys systems—primarily caused by axial translation rather than vertical displacement—contributed to screw–vertebra interface stress, influenced by the underlying disc or bone degeneration. Conclusions: Modulating the cord pretension in DTO instrumentation effectively lessened the interface stress occurring at the screw–vertebra junction and adjacent facet joints, contributing to a reduced incidence of pedicle screw loosening, ASD, and revision rates. The modified DTO system, incorporating minimal decompression and preserving the posterior complex at the dynamic level, may be biomechanically favourable and clinically effective for managing transitional degeneration over the mid-term. Full article

Background/Objectives: Vitamin D deficiency contributes to pathological vertebral fragility (path-VF), including fragility fractures and early pedicle screw loosening after posterior instrumented spinal fusion (PISF). Supplementation practices remain inconsistent. This retrospective study evaluated whether patients with path-VF receive appropriate vitamin D3 (Vit.D3) supplementation and assessed the dose–response relationship between daily intake and path-VF risk, particularly in older adults. Methods: A total of 210 patients treated with kyphoplasty or PISF (2022–2023) were classified into a path-VF or control group. Daily oral Vit.D3 intake was categorised as Zero- (0 IU), Low- (<2000 IU), or High-Dose (≥2000 IU). Statistical analyses were performed for each dosage group, including subgroup analyses for patients aged ≥67.5 years. Vertebral BMD was estimated using mean Hounsfield Units (HU) from T11–L5. Results: Patients in the path-VF group received significantly lower Vit.D3 doses than controls (1431.4 ± 1055.7 vs. 2366.7 ± 1186.7 IU/day, p < 0.001). Low-dose supplementation was associated with a markedly increased risk of path-VF compared with high-dose in the overall cohort (OR = 6.5, p = 0.003) and in patients aged ≥67.5 years (OR = 8.6, p = 0.008). Logistic regression identified a threshold of 1900 IU/day (AUC = 0.805). Mean vertebral HU values were significantly lower in the path-VF group than in controls (71.9 ± 29.1 vs. 133.5 ± 52.6, p < 0.001), and no consistent HU gains were observed with increasing Vit.D3 dosage. Conclusions: Low-dose Vit.D3 supplementation was associated with increased path-VF risk, especially in patients aged >67.5 years. Patients without path-VF had received significantly higher doses, suggesting broader benefits of adequate Vit.D3 beyond bone density. A daily intake above 1900 IU may serve as a practical threshold for at-risk elderly patients. Full article

Can human–machine hybrid systems (HMHs) constitute genuine collective agents? This paper defends an affirmative answer. I argue that HMHs achieve collective intentionality without shared consciousness by satisfying the following three functional criteria: goal alignment, functional complementarity, and stable interactivity. Against this functionalist account, the following two objections arise: (1) the cognitive bloat problem, that functional criteria cannot distinguish genuine cognitive integration from mere tool use; and (2) the phenomenological challenge, that AI’s lack of practical reason reduces human–AI interaction to subject–tool relations. I respond by distinguishing constitutive from instrumental functional contributions and showing that collective agency requires stable functional integration, not phenomenological fusion. The result is what I call Functional Hybrid Collective Agents (FHCAs), which are systems exhibiting irreducible collective intentionality through deep human–AI coupling. Full article

Background/Objectives: Pathological vertebral fragility (path-VF) increases the risk of osteoporotic fractures and pedicle screw loosening (PSL) after posterior instrumented spinal fusion (PISF). While WHO body mass index (BMI) categories broadly identify risks related to underweight and obesity, fixed thresholds may inadequately reflect vertebral fragility risks among elderly patients, especially within the normal-weight range. This study investigates whether current BMI classifications sufficiently capture the risk of path-VF in older adults. Methods: This retrospective study included 225 patients who underwent kyphoplasty or PISF (2022–2023). Path-VF was defined by non-tumorous fractures, screw reinforcement, or PSL within six months without prior reinforcement. Patients were grouped into the path-VF (n = 94) and control (n = 131) groups. HU and BMI values, BMI-related ORs, and age trends were analysed, and a logistic regression was performed. Results: Mean HU values were significantly lower in the path-VF group (71.37 ± 30.50) than in controls (130.35 ± 52.53, p < 0.001). Path-VF females (26.26 ± 5.38) had a lower BMI than the control females (29.33 ± 5.98, p = 0.002); no difference was found in males. Normal-weight females showed a borderline risk for path-VF (OR 2.03, p = 0.0495). Obesity (OR_male 0.31/OR_female 0.37) and being male and overweight (OR 0.21) were protective (all p < 0.05). BMI declined with age in path-VF males (p = 0.001) but increased in the controls (p = 0.023). A logistic regression identified a BMI < 22.5 kg/m² and age > 67.5 years as significant risk thresholds. Notably, 20.2% of path-VF patients over 67.5 had a normal weight, suggesting a potentially overlooked subgroup. Conclusions: The current WHO lower limit for normal BMI (18.5 kg/m²) may underestimate the risk of path-VF in patients older than 67.5 years, potentially overlooking 24.7% of cases. The results offer a new approach for clinicians to interpret BMI values at the lower end of the normal range (<22.5 kg/m²) with caution in elderly patients undergoing spinal surgery. Full article

Background/Objectives: Previous studies have reported satisfactory outcomes and low rates of instrumentation-related complications (IRCs) following nonfusion posterior fixation in patients with metastatic spinal tumors (MSTs). However, to adequately assess the longevity and durability of nonfusion instrumentation in patients with longer life expectancy, an extended follow-up period is essential. This study aims to evaluate the incidence of and risk factors for IRCs in patients with MSTs who underwent nonfusion posterior fixation and had radiographic follow-up data available for at least one year postoperatively. Methods: Consecutive data were collected from patients who underwent pedicle screw-based posterior fixation without fusion for MSTs in the thoracic and/or lumbar region from 2005 to 2018. The IRCs included screw loosening, screw pull-out, and metal breakage. The IRC-free survival and related factors were analyzed by Kaplan–Meier survivorship analysis with the log-rank test within a minimum follow-up period of one year. A multivariate analysis was performed using a Cox proportional-hazards regression model. Results: In total, 61 patients were included. The mean follow-up period was 28.3 months (range: 12.0–102.6 months). There were 27 cases (44.2%) of IRCs, including 22 cases of screw loosening, four cases of screw pull-out, and one case of rod breakage, at an average of 9.6 months (range: 1.0–38.1 months). The median IRC-free survival was 38.1 months (range: 1.0–102.6 months). Only three patients experienced pain aggravation with IRCs. No revision surgery was performed. A multivariate analysis identified that fixation length was a risk factor for IRCs (odds ratio: 0.358, 95% confidence interval: 0.114–0.888; p = 0.027). Conclusions: IRCs are frequent but mostly asymptomatic after nonfusion posterior fixation in patients with MSTs followed up for at least one year. Overall, the IRC-free survival was long enough considering the patient survival. Fixation length was a significant risk factor for IRCs regardless of MST location. Full article

Background: Structured titanium (ST) cages are designed to enhance osseointegration and fusion in lumbar interbody procedures. However, clinical and radiological outcomes following TLIF using ST cages—particularly with or without adjacent-level dynamic stabilization (DSS)—have not been widely reported. Objective: To evaluate 12-month fusion outcomes and patient-reported outcomes (PROMs) after TLIF with structured titanium cages, comparing cases with and without adjacent-level DSS. Methods: In this retrospective cohort study, 82 patients undergoing TLIF with ST cages were analyzed—41 with hybrid instrumentation (TLIF + DSS) and 41 with TLIF alone. PROMs (ODI, VAS for back and leg pain, EQ-5D-5L) were assessed preoperatively and at 12 months. Fusion was assessed via CT scans at 12 months. Results: PROMs significantly improved over time in both groups (p < 0.001 for ODI, VAS back, VAS leg), but there were no significant differences between the hybrid and non-hybrid groups. Overall, the interbody fusion rate was 84%. Complete fusion was observed in 84% of the hybrid group and 80% of the TLIF-only group (p = 0.716), with very low rates of non-union. Conclusions: Structured titanium cages demonstrated excellent 1-year fusion rates and supported significant clinical improvement after TLIF. The addition of dynamic stabilization had no measurable effect on patient-reported or radiological outcomes at 12 months. Long-term studies are needed to assess any potential effect of DSS on adjacent segment disease. Full article

Background/Objectives: While anterior lumbar interbody fusion (ALIF) is a well-established treatment for degenerative lumbar spine pathology, the timing and pace of postoperative recovery remain poorly defined. Understanding these temporal trends is clinically important for setting patient expectations and optimizing postoperative care. Methods: This retrospective single-institution study evaluated functional recovery in patients undergoing primary, single-level stand-alone (SA) ALIF, or with percutaneous posterior instrumentation (PI). Patient-reported outcome measures (PROMs), including the Oswestry Disability Index (ODI), the Visual Analog Scale (VAS) for back and leg pain, and the SF-12 Physical Component Score (PCS), were assessed preoperatively and at 2 weeks, 6 weeks, 3 months, 6 months, 1 year, and 2 years postoperatively. Achievement of minimum clinically important difference (MCID), global rating change (GRC), and return-to-activity milestones were also analyzed. Results: A total of 143 patients were included (90 SA; 53 PI). PROMs showed significant improvement through 1 year. VAS-back improved by 2 weeks, while ODI and SF12 PCS initially worsened but improved after 6 weeks. By 6 months, over half of the cohort achieved MCID, with continued gains through 1 year. Most patients returned to driving and work, and over 90% discontinued narcotics. Recovery trajectories were comparable between groups, despite early delays in the instrumented cohort. Conclusions: These findings provide time-specific recovery benchmarks that can guide surgical decision-making, patient education, and expectations around functional milestones. Full article

Background/Objectives: Spinal muscular atrophy (SMA) is a neuromuscular disorder frequently associated with progressive scoliosis requiring posterior spinal fusion (PSF). While Nusinersen offers significant clinical benefit, its intrathecal administration is challenging in patients with extensive spinal instrumentation and solid fusion. This study aimed to evaluate the safety, feasibility, and patient acceptance of lumbar laminectomy as a method to restore intrathecal access for repeated Nusinersen delivery in this population. Methods: A retrospective review was conducted in eleven patients with SMA who underwent lumbar laminectomy following prior PSF and confirmed radiographic fusion. Surgical data, injection outcomes, and patient-reported experiences were collected. A structured questionnaire assessed technical success, imaging requirements, sedation, functional response, and satisfaction. Results: Nine out of eleven patients (81.8%) successfully initiated intrathecal Nusinersen therapy through the laminectomy window, receiving a mean of 11.7 injections (range: 10–14). Imaging guidance was used in five cases; three required sedation or anesthesia. Intraoperative dural tears occurred in three patients and were managed without complications. Eight out of nine treated patients reported subjective motor improvement and expressed willingness to undergo the procedure again. No hardware revisions or major adverse events were observed during a mean follow-up of 48.8 months. Conclusions: Lumbar laminectomy is a viable and well-tolerated technique to establish intrathecal access in SMA patients with prior PSF. This approach enables sustained drug delivery and may remain clinically relevant as new intrathecal therapies emerge. Full article