Annals of Biomedical Engineering最新文献

{"title":"Laboratory Evaluation of a Wearable Instrumented Headband for Rotational Head Kinematics Measurement.","authors":"Anu Tripathi, Yang Wan, Sushant Malave, Sheila Turcsanyi, Alice Lux Fawzi, Alison Brooks, Haneesh Kesari, Traci Snedden, Peter Ferrazzano, Christian Franck, Rika Wright Carlsen","doi":"10.1007/s10439-025-03746-7","DOIUrl":"10.1007/s10439-025-03746-7","url":null,"abstract":"<p><strong>Purpose: </strong>Mild traumatic brain injuries (mTBI) are a highly prevalent condition with heterogeneous outcomes between individuals. A key factor governing brain tissue deformation and the risk of mTBI is the rotational kinematics of the head. Instrumented mouthguards are a widely accepted method for measuring rotational head motions, owing to their robust sensor-skull coupling. However, wearing mouthguards is not feasible in all situations, especially for long-term data collection. Therefore, alternative wearable devices are needed. In this study, we present an improved design and data processing scheme for an instrumented headband.</p><p><strong>Methods: </strong>Our instrumented headband utilizes an array of inertial measurement units (IMUs) and a new data processing scheme based on continuous wavelet transforms to address sources of error in the IMU measurements. The headband performance was evaluated in the laboratory on an anthropomorphic test device, which was impacted with a soccer ball to replicate soccer heading.</p><p><strong>Results: </strong>When comparing the measured peak rotational velocities (PRV) and peak rotational accelerations (PRA) between the reference sensors and the headband for impacts to the front of the head, the correlation coefficients (r) were 0.80 and 0.63, and the normalized root mean square error (NRMSE) values were 0.20 and 0.28, respectively. However, when considering all impact locations, r dropped to 0.42 and 0.34 and NRMSE increased to 0.5 and 0.41 for PRV and PRA, respectively.</p><p><strong>Conclusion: </strong>This new instrumented headband improves upon previous headband designs in reconstructing the rotational head kinematics resulting from frontal soccer ball impacts, providing a potential alternative to instrumented mouthguards.</p>","PeriodicalId":7986,"journal":{"name":"Annals of Biomedical Engineering","volume":" ","pages":"1944-1961"},"PeriodicalIF":3.0,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12283827/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144075486","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of Interphase and Interpulse Delays on Tissue Impedance and Pulsed Field Ablation.","authors":"Edward J Jacobs, Pedro P Santos, Rafael V Davalos","doi":"10.1007/s10439-025-03757-4","DOIUrl":"10.1007/s10439-025-03757-4","url":null,"abstract":"<p><strong>Purpose: </strong>High-frequency irreversible electroporation (H-FIRE) is a pulsed field ablation (PFA) technique that employs a series of high-voltage, microseconds-long positive and negative pulses, separated by interphase (d1) and interpulse (d2) delays to non-thermally ablate tissue. Previous experimental and computational data suggest an impact of delays on nerve excitation and electrochemical effects. However, the impact of delays on PFA outcomes, such as change in resistance and ablation generation, has only recently started to be elucidated.</p><p><strong>Methods: </strong>While recording the applied voltage and currents, we delivered a series of increasing voltages, termed voltage ramps, into tuber and cardiac tissues using both needle electrode pairs and flat plate electrodes. Tissues were stained for metabolic activity to measure irreversible electroporation areas following treatment.</p><p><strong>Results: </strong>Our findings support previous in vitro data that delays do not significantly affect ablation areas. While there were significant differences in applied current, resistance, and conductivity between different pulse widths at sub-electroporation electric fields, we found no significant differences after inducing electroporation between different delays and pulse widths. Consequently, since delays do not affect ablation areas or local conductivity, the data suggests that delays should not affect the electric field threshold or Joule heating within the tissue.</p><p><strong>Conclusion: </strong>The findings presented here provide critical insights into electroporation-dependent tissue conductivity changes from H-FIRE with implications for improving H-FIRE parameterization and computational models for treatment planning in cancer and cardiac pulsed field ablation.</p>","PeriodicalId":7986,"journal":{"name":"Annals of Biomedical Engineering","volume":" ","pages":"1962-1974"},"PeriodicalIF":3.0,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12283778/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144085714","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Gait Characteristics Associated with Walking Speed in Postoperative Patients with Adult Spinal Deformity Extracted by Machine Learning.","authors":"Naoto Mano, Kimihiko Mori, Tomohiro Ushikubo, Takayuki Konishi, Shun Ito, Jin Kuramoto, Masayuki Ishihara, Kimitaka Hase","doi":"10.1007/s10439-025-03750-x","DOIUrl":"10.1007/s10439-025-03750-x","url":null,"abstract":"<p><strong>Purpose: </strong>Patients with adult spinal deformity (ASD) are unable to walk faster even after spinal fixation. Gait rehabilitation that focuses on movements associated with reduced speed may help improve gait function. This study aimed to identify the gait characteristics associated with walking velocity in postoperative patients with ASD.</p><p><strong>Methods: </strong>Three-dimensional gait analysis was performed in 62 postoperative patients with ASD and 105 healthy volunteers. A dimensionality reduction method, based on data from the healthy cohort, was applied to 194 gait characteristics of the patients. Then, the Markov Chain Monte Carlo method sampled the gait characteristics related to speed, and k-means clustering categorized the gait patterns. The relationships between the extracted gait characteristics and velocity were assessed using multiple regression analysis within each cluster.</p><p><strong>Results: </strong>Hip sagittal angle and moment (β = - 0.47 to 0.42) were significantly associated with postoperative velocity in all the patients (R² = 0.834). Two clusters were identified, and hip sagittal moments at contralateral contact and toe-off (β = - 0.58 and 0.68, respectively) were associated with velocity in the group that walked faster (R² = 0.634). Maximum ankle plantarflexion moment and hip flexion power (β = 0.53 and 0.33, respectively) were associated with velocity in the group that walked slowly (R² = 0.448).</p><p><strong>Conclusion: </strong>Larger hip joint movement may play a crucial role in enhancing gait velocity because the spinal fixation limits spino-pelvic movement. To improve gait speed, postoperative older adults with ASD who walk slowly may require new rehabilitation strategies that exert more ankle plantarflexion moment and develop an adequate stance phase to facilitate hip extension.</p>","PeriodicalId":7986,"journal":{"name":"Annals of Biomedical Engineering","volume":" ","pages":"1797-1809"},"PeriodicalIF":3.0,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143958051","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An In Silico Model to Examine the Interaction Between Implant Degradation and Fracture Healing Under Mechanical Loading.","authors":"Ruisen Fu, Xurun Zhao, Yang Liu, Aike Qiao, Haisheng Yang","doi":"10.1007/s10439-025-03741-y","DOIUrl":"10.1007/s10439-025-03741-y","url":null,"abstract":"<p><p>Biodegradable implants are promising for fracture fixation but they have not been applied to the load-bearing skeletal sites. A critical issue is how implant degradation and fracture healing affect each other under mechanical loading. To address this issue, we first developed a finite element model of a long bone fracture fixed with a Zn alloy-based screw-plate system, where implant degradation and bone healing were simulated based upon the continuum damage mechanics and mechano-regulated tissue differentiation algorithm, respectively. For comparison, non-degradable Ti alloy implant with normal bone healing and non-healing fracture with normal implant degradation were served as two reference controls. In terms of the effect of implant degradation on bone healing, the results indicated that implant degradation resulted in a greater volume of newly formed bone within the callus (16% for the degradable implant vs 12% for the non-degradable implant) and a better biomechanical recovery of the fractured bone (bone stiffness fraction: 107% vs 95%) at week 8. Regarding the effect of bone healing on implant degradation, fracture healing led to a significant decrease in the degradation rate of the implant (implant stiffness fraction at week 4: 8% for non-healing vs 40% for healing) and an increase in the overall period from 4 to 8 weeks for a complete degradation of the implant. These results together suggest that implant degradation and fracture healing significantly affect each other under mechanical loading. The in silico model developed here may provide a valuable platform to consider interactions between material degradation and bone healing when designing biodegradable implants for orthopaedic internal fixation at the load-bearing sites.</p>","PeriodicalId":7986,"journal":{"name":"Annals of Biomedical Engineering","volume":" ","pages":"1919-1930"},"PeriodicalIF":3.0,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144075483","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluating Polo Helmet Performance Across Different Impact Test Systems.","authors":"Nicole E-P Stark, Mark T Begonia, Steve Rowson","doi":"10.1007/s10439-025-03731-0","DOIUrl":"10.1007/s10439-025-03731-0","url":null,"abstract":"<p><strong>Purpose: </strong>This study evaluated head impact response between different helmet impact test systems by comparing the performance of ten polo helmets.</p><p><strong>Methods: </strong>Helmets were evaluated using three test systems: a twin-wire guided drop tower, an oblique drop tower, and an impact pendulum. Impact tests were conducted at matched locations (front boss, side, rear boss) and speeds (3.46, 5.46 m/s). We employed a linear mixed model with helmet model as a random effect and calculated the least square mean differences between systems for peak linear acceleration (PLA), peak rotational acceleration (PRA), peak rotational velocity (PRV), and concussion risk. Correlations between systems by impact speed were explored, using linear models of each system as a function of the others, and calculated Spearman rank correlation coefficients between test systems for each dependent variable.</p><p><strong>Results: </strong>Our results found distinct differences in PRA and concussion risk between the oblique and the pendulum impact systems due to the driving force. The acceleration range across helmet models was substantial, and responses differed between test systems at matched impact conditions. However, there were similarities between test systems in the rank order of helmet models. Head acceleration differences between helmets translated to larger differences in concussion risk between helmet models.</p><p><strong>Conclusion: </strong>These trends provide a framework for comparing the headform's response across varying loading conditions. When selecting a test system to evaluate helmets for a specific sport, it is essential to consider the relevant impact conditions and loading patterns to ensure that laboratory tests accurately represent real-world scenarios.</p>","PeriodicalId":7986,"journal":{"name":"Annals of Biomedical Engineering","volume":" ","pages":"1810-1833"},"PeriodicalIF":3.0,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12283464/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143952514","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Relation Between Hemiparetic Gait Patterns and Walking Function After Stroke, as Measured with Wearable Sensors.","authors":"Brice Thomas Cleland, Madeline Kim, Sangeetha Madhavan","doi":"10.1007/s10439-025-03754-7","DOIUrl":"10.1007/s10439-025-03754-7","url":null,"abstract":"<p><strong>Purpose: </strong>After stroke, walking is characterized by hemiparetic patterns, quantified with force sensitive walkways and motion capture systems. Some joint-level kinematic patterns of walking also can be obtained with wearable sensors. The purpose of this project was to measure joint-level kinematic patterns during walking with wearable sensors and determine the association with walking speed and endurance in individuals with chronic stroke.</p><p><strong>Methods: </strong>In this cross-sectional observational study, participants donned APDM Opal wearable sensors during walking tests (10-meter walk test or 6-min walk test). We extracted joint-level kinematic variables of elevation at midswing, circumduction, foot strike angle, and toe-off angle. Associations of each variable with walking speed and endurance were tested, and significantly associated variables were entered into a regression model.</p><p><strong>Results: </strong>68 individuals with chronic stroke were included. We found that the less affected foot strike angle, less affected toe-off angle, and more affected toe-off angle were significant predictors of walking speed (R² ≥ 0.71, p < 0.001). Less affected toe-off angle, more affected foot strike angle, and more affected toe-off angle were significant predictors of walking endurance (R² ≥ 0.67, p < 0.001).</p><p><strong>Conclusion: </strong>We found consistent evidence that greater toe-off angle (may reflect greater push-off) and lesser foot strike angle (may reflect lesser foot drop) were important predictors of greater walking speed and endurance. Our results suggest that wearable sensors can provide important information about joint-level kinematic patterns that are important for walking function. This information could help therapists target interventions toward specific deficits or compensatory patterns to improve walking.</p>","PeriodicalId":7986,"journal":{"name":"Annals of Biomedical Engineering","volume":" ","pages":"1890-1902"},"PeriodicalIF":5.4,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12283793/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144075489","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Predicting Knee Osteoarthritis Severity from Radiographic Predictors: Data from the Osteoarthritis Initiative.","authors":"Teemu A T Nurmirinta, Mikael J Turunen, Jussi Tohka, Mika E Mononen, Mimmi K Liukkonen","doi":"10.1007/s10439-025-03740-z","DOIUrl":"10.1007/s10439-025-03740-z","url":null,"abstract":"<p><strong>Purpose: </strong>In knee osteoarthritis (KOA) treatment, preventive measures to reduce its onset risk are a key factor. Among individuals with radiographically healthy knees, however, future knee joint integrity and condition cannot be predicted by clinically applicable methods. We investigated if knee joint morphology derived from widely accessible and cost-effective radiographs could be helpful in predicting future knee joint integrity and condition.</p><p><strong>Methods: </strong>We combined knee joint morphology with known risk predictors such as age, height, and weight. Baseline data were utilized as predictors, and the maximal severity of KOA after 8 years served as a target variable. The three KOA categories in this study were based on Kellgren-Lawrence grading: healthy, moderate, and severe. We employed a two-stage machine learning model that utilized two random forest algorithms. We trained three models: the subject demographics (SD) model utilized only SD; the image model utilized only knee joint morphology from radiographs; the merged model utilized combined predictors. The training data comprised an 8-year follow-up of 1222 knees from 683 individuals.</p><p><strong>Results: </strong>The SD- model obtained a weighted F1 score (WF1) of 77.2% and a balanced accuracy (BA) of 65.6%. The Image-model performance metrics were lowest, with a WF1 of 76.5% and BA of 63.8%. The top-performing merged model achieved a WF1 score of 78.3% and a BA of 68.2%.</p><p><strong>Conclusion: </strong>Our two-stage prediction model provided improved results based on performance metrics, suggesting potential for application in clinical settings.</p>","PeriodicalId":7986,"journal":{"name":"Annals of Biomedical Engineering","volume":" ","pages":"1852-1861"},"PeriodicalIF":3.0,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12283875/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143952512","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Self-Tension Screw for Meniscal Root Repair: Biomechanical Properties and Design Considerations for Optimal Outcomes.","authors":"Mojtaba Fattahi Bafghi, Majid Baniassadi, Mostafa Baghani, Arash Sharafatvaziri, Soodabeh Esfandiari, Ramin Shayan-Moghadam, Sohrab Keyhani, Morad Karimpour, Daniel George","doi":"10.1007/s10439-025-03748-5","DOIUrl":"10.1007/s10439-025-03748-5","url":null,"abstract":"<p><strong>Background: </strong>The meniscus is a collagenous and elastic tissue that plays a crucial role in preventing wear and tear within the knee joint. Meniscus root tears are a common knee pathology that can significantly impact joint function. One of the prevalent surgical techniques for repairing meniscus root tears is the transtibial pull-out method, favored by many orthopedic surgeons. It is essential to consider that displacement of the meniscus root and inadequate stabilization during the rehabilitation period are likely contributing factors to the failure of meniscus root repair outcomes. Understanding these challenges is vital for improving surgical techniques and postoperative care to enhance patient recovery and joint stability.</p><p><strong>Purpose: </strong>Meniscal root tears pose a significant challenge in orthopedics, disrupting the delicate mechanics of the knee. This study introduces a novel self-tension screw designed for meniscal root repair, addressing the limitations associated with traditional screws.</p><p><strong>Methods: </strong>14 Bovine cadaveric specimens were employed to conduct biomechanical evaluations and compare the new self-tension screw with a conventional washer screw system used in these surgeries.</p><p><strong>Results: </strong>From cyclic loading tests, comparable displacement trends are observed 3.092 ± 0.258 mm in Self-tension screw group and 2.629 ± 0.727 mm in Washer screw. load-to-failure assessments demonstrated superior tolerance in the washer screw by 391.34 ± 60.203 N that is significantly better than the self-tension screw group with a load tolerance of 136.58 ± 25.48 N. Stiffness analyses indicated greater structural stability in the washer screw (22.77 ± 4.234) over self-tension screw (15.2 ± 4.89).</p><p><strong>Conclusion: </strong>The innovative self-tension mechanism of the screw, generating tension during bone channel engagement, suggests a potential breakthrough in addressing manual tensioning challenges.</p>","PeriodicalId":7986,"journal":{"name":"Annals of Biomedical Engineering","volume":" ","pages":"1862-1872"},"PeriodicalIF":3.0,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143962891","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Point Cloud Generation Network for Automatic Prediction of Postoperative Maxillofacial Soft Tissue.","authors":"Ruiyang Li, Bimeng Jie, Boxuan Han, Yuchao Zheng, Chengyi Wang, Xuan Yang, Yi Zhang, Hongen Liao, Yang He, Longfei Ma","doi":"10.1007/s10439-025-03758-3","DOIUrl":"10.1007/s10439-025-03758-3","url":null,"abstract":"<p><strong>Purpose: </strong>In the planning of maxillofacial surgery, accurately evaluating the postoperative soft tissue area is crucial. This allows doctors to provide patients with better morphological recovery while ensuring the restoration of normal functional areas. This study aims to develop an advanced automatic algorithm for the completion of soft tissue defects, enhancing the accuracy and effectiveness of surgical planning.</p><p><strong>Methods: </strong>We introduce a point cloud completion method based on Generative Adversarial Networks. Firstly, we remove the defective regions, reserving the healthy tissues and converting them into point clouds. Then, using the soft tissue completion network, we reconstruct the defective areas and generate the corresponding point cloud images. Finally, we combine the healthy point cloud with the generated defective regions to produce a complete soft tissue image and model of the patient's face.</p><p><strong>Results: </strong>To validate our approach, we conduct qualitative and quantitative experiments on 20 normal individuals (10 males and 10 females). Compared with several existing algorithms, our method shows superior significance in soft tissue prediction. The Root Mean Squared Error between the generated model and ground truth is 1.45 ± 0.25 mm, and the Surface Distance error is 0.69 ± 0.13 mm. The visualization results show that using our network to generate soft tissue at the defect site is more structurally consistent.</p><p><strong>Conclusion: </strong>This study introduces a novel point cloud generation network for reconstructing facial soft tissue images, which provides accurate and structurally consistent morphological outcomes. The proposed method shows great potential in improving the quality and accuracy of surgical planning in maxillofacial surgery.</p>","PeriodicalId":7986,"journal":{"name":"Annals of Biomedical Engineering","volume":" ","pages":"1975-1985"},"PeriodicalIF":3.0,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144075481","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Resting Supine for 45 Minutes Yields Consistent Baseline Lumbar Intervertebral Disc Height in Asymptomatic Participants.","authors":"Nicole E Zimmer, James A Coppock, Andrzej S Kosinski, Charles E Spritzer, Adam P Goode, Louis E DeFrate","doi":"10.1007/s10439-025-03749-4","DOIUrl":"10.1007/s10439-025-03749-4","url":null,"abstract":"<p><strong>Purpose: </strong>Intervertebral disc (IVD) height fluctuates diurnally as the spine is exposed to periods of high and low loading. Therefore, accounting for loading history prior to measuring in vivo IVD height is important when investigating IVD mechanics. However, there is a lack of consensus in the literature on in vivo lumbar IVD height recovery times under low loads. Therefore, we sought to determine whether a 45-minute supine rest period yields a consistent baseline for measuring in vivo lumbar IVD height across different times of day.</p><p><strong>Methods: </strong>Nine asymptomatic participants underwent magnetic resonance (MR) imaging following a 45-minute supine rest, beginning at 7:00 AM on one visit day and mid-day (10:30 AM-12:30 PM) on a separate day. MR images were manually segmented, and the mean heights of the L1-L2 through L5-S1 IVDs were measured. Three MR scans were segmented in triplicate to evaluate segmentation repeatability.</p><p><strong>Results: </strong>Intraclass correlation coefficients (ICCs) and root mean squared error (RMSE) were calculated for different times of day (ICC: 0.96; RMSE: 0.08 mm) and for segmentation repeatability (ICC: 0.97; RMSE: 0.08 mm).</p><p><strong>Conclusion: </strong>ICCs indicated excellent reliability, and RMSEs were below 1% of IVD height, suggesting that a 45-minute supine rest period provides a consistent baseline for measuring lumbar IVD height between 7:00 AM and 12:30 PM.</p>","PeriodicalId":7986,"journal":{"name":"Annals of Biomedical Engineering","volume":" ","pages":"1883-1889"},"PeriodicalIF":3.0,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12286735/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143952931","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}