{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,14]],"date-time":"2026-08-14T12:39:35Z","timestamp":1786711175822,"version":"build-2736575974"},"reference-count":36,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2026,8,14]],"date-time":"2026-08-14T00:00:00Z","timestamp":1786665600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100015406","name":"Tianjin Science and Technology Major Project","doi-asserted-by":"publisher","award":["25ZXWZSY00010"],"award-info":[{"award-number":["25ZXWZSY00010"]}],"id":[{"id":"10.13039\/501100015406","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100015406","name":"Tianjin Municipal Science and Technology Program","doi-asserted-by":"publisher","award":["25JCZDJC01350"],"award-info":[{"award-number":["25JCZDJC01350"]}],"id":[{"id":"10.13039\/501100015406","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["82405109"],"award-info":[{"award-number":["82405109"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"award":["82405109"],"award-info":[{"award-number":["82405109"]}],"id":[{"id":"https:\/\/ror.org\/01h0zpd94","id-type":"ROR","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100010882","name":"Tianjin Municipal Education Commission","doi-asserted-by":"publisher","award":["2024ZXZD001"],"award-info":[{"award-number":["2024ZXZD001"]}],"id":[{"id":"10.13039\/501100010882","id-type":"DOI","asserted-by":"publisher"}]},{"award":["2024ZXZD001"],"award-info":[{"award-number":["2024ZXZD001"]}],"id":[{"id":"https:\/\/ror.org\/01z7y3r39","id-type":"ROR","asserted-by":"publisher"}]},{"name":"Key Laboratory of Key Technologies and Equipment for Medical Rescue","award":["YJBKFKT202508"],"award-info":[{"award-number":["YJBKFKT202508"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Bioengineering"],"abstract":"<jats:p>Imaging underpins the diagnosis and structural staging of osteonecrosis of the femoral head (ONFH) but does not directly quantify functional impairment during weight-bearing walking. We developed a subject-level ONFH classification framework using multilevel gait features acquired with wearable inertial measurement units (IMUs). Thirty healthy controls and 21 participants with imaging-confirmed ONFH completed self-paced walking trials recorded at 100 Hz. Gait cycles were segmented from bilateral foot-contact events, normalized to 120 points, and represented as 17-channel kinematic waveforms, 22-dimensional cycle-level scalar features, and 7-channel dynamic absolute asymmetry waveforms. These inputs were encoded by CNN\u2013CBAM\u2013BiLSTM, multilayer perceptron, and one-dimensional convolutional branches, respectively, and fused at the feature level. Evaluation used 51-fold leave-one-subject-out cross-validation, training-fold-only preprocessing, within-subject probability averaging, and five predefined random seeds. The five-seed ensemble achieved an accuracy of 0.9412, sensitivity of 0.8571, specificity of 1.0000, F1-score of 0.9231, and area under the receiver operating characteristic curve of 0.9556. Ablation analysis identified the scalar-feature vector as the principal source of incremental performance; the dynamic asymmetry branch contributed complementary information only in the complete model. These findings provide preliminary evidence for further evaluation of wearable gait-based ONFH classification in independent cohorts and objective functional assessment.<\/jats:p>","DOI":"10.3390\/bioengineering13080922","type":"journal-article","created":{"date-parts":[[2026,8,14]],"date-time":"2026-08-14T11:57:46Z","timestamp":1786708666000},"page":"922","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Subject-Level Classification of Osteonecrosis of the Femoral Head from Wearable IMU Gait Data Using Multilevel Feature Fusion"],"prefix":"10.3390","volume":"13","author":[{"given":"Xin","family":"Yu","sequence":"first","affiliation":[{"name":"School of Biomedical Engineering and Technology, Tianjin Medical University, Tianjin 300070, China"},{"name":"Tianjin Orthopedic Institute, Tianjin 300050, China"},{"name":"Tianjin Institute of Integrated Traditional Chinese and Western Medicine for Orthopedics, Tianjin 300050, China"},{"name":"Tianjin Key Laboratory of Orthopedic Biomechanics and Medical Engineering, Tianjin 300050, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yan","family":"Wang","sequence":"additional","affiliation":[{"name":"Tianjin Orthopedic Institute, Tianjin 300050, China"},{"name":"Tianjin Institute of Integrated Traditional Chinese and Western Medicine for Orthopedics, Tianjin 300050, China"},{"name":"Tianjin Key Laboratory of Orthopedic Biomechanics and Medical Engineering, Tianjin 300050, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tiancheng","family":"Ma","sequence":"additional","affiliation":[{"name":"Tianjin Orthopedic Institute, Tianjin 300050, China"},{"name":"Tianjin Institute of Integrated Traditional Chinese and Western Medicine for Orthopedics, Tianjin 300050, China"},{"name":"Tianjin Key Laboratory of Orthopedic Biomechanics and Medical Engineering, Tianjin 300050, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xinwu","family":"Duan","sequence":"additional","affiliation":[{"name":"Tianjin Orthopedic Institute, Tianjin 300050, China"},{"name":"Tianjin Institute of Integrated Traditional Chinese and Western Medicine for Orthopedics, Tianjin 300050, China"},{"name":"Tianjin Key Laboratory of Orthopedic Biomechanics and Medical Engineering, Tianjin 300050, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0009-5641-9760","authenticated-orcid":false,"given":"Jianxiong","family":"Ma","sequence":"additional","affiliation":[{"name":"Tianjin Orthopedic Institute, Tianjin 300050, China"},{"name":"Tianjin Institute of Integrated Traditional Chinese and Western Medicine for Orthopedics, Tianjin 300050, China"},{"name":"Tianjin Key Laboratory of Orthopedic Biomechanics and Medical Engineering, Tianjin 300050, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,8,14]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Hines, J.T., Jo, W.L., Cui, Q., Mont, M.A., Koo, K.H., Cheng, E.Y., Goodman, S.B., Ha, Y.C., Hernigou, P., and Jones, L.C. 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