{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T01:14:59Z","timestamp":1760058899603,"version":"build-2065373602"},"reference-count":39,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2025,5,3]],"date-time":"2025-05-03T00:00:00Z","timestamp":1746230400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Dys4Vet","award":["POCI-01-0247-FEDER-046914","COMPETE2020"],"award-info":[{"award-number":["POCI-01-0247-FEDER-046914","COMPETE2020"]}]},{"name":"the European Regional Development Fund (ERDF)","award":["POCI-01-0247-FEDER-046914","COMPETE2020"],"award-info":[{"award-number":["POCI-01-0247-FEDER-046914","COMPETE2020"]}]},{"name":"the Operational Programme for Competitiveness and Internationalisation (OPCI)","award":["POCI-01-0247-FEDER-046914","COMPETE2020"],"award-info":[{"award-number":["POCI-01-0247-FEDER-046914","COMPETE2020"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Applied Sciences"],"abstract":"<jats:p>Canine hip dysplasia (CHD) screening relies on radiographic assessment, but traditional scoring methods often lack consistency due to inter-rater variability. This study presents an AI-driven system for automated measurement of the femoral head center to dorsal acetabular edge (FHC\/DAE) distance, a key metric in CHD evaluation. Unlike most AI models that directly classify CHD severity using convolutional neural networks, this system provides an interpretable, measurement-based output to support a more transparent evaluation. The system combines a keypoint regression model for femoral head center localization with a U-Net-based segmentation model for acetabular edge delineation. It was trained on 7967 images for hip joint detection, 571 for keypoints, and 624 for acetabulum segmentation, all from ventrodorsal hip-extended radiographs. On a test set of 70 images, the keypoint model achieved high precision (Euclidean Distance = 0.055 mm; Mean Absolute Error = 0.0034 mm; Mean Squared Error = 2.52 \u00d7 10\u22125 mm2), while the segmentation model showed strong performance (Dice Score = 0.96; Intersection over Union = 0.92). Comparison with expert annotations demonstrated strong agreement (Intraclass Correlation Coefficients = 0.97 and 0.93; Weighted Kappa = 0.86 and 0.79; Standard Error of Measurement = 0.92 to 1.34 mm). By automating anatomical landmark detection, the system enhances standardization, reproducibility, and interpretability in CHD radiographic assessment. Its strong alignment with expert evaluations supports its integration into CHD screening workflows for more objective and efficient diagnosis and CHD scoring.<\/jats:p>","DOI":"10.3390\/app15095087","type":"journal-article","created":{"date-parts":[[2025,5,4]],"date-time":"2025-05-04T20:10:27Z","timestamp":1746389427000},"page":"5087","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["A Computer-Aided Approach to Canine Hip Dysplasia Assessment: Measuring Femoral Head\u2013Acetabulum Distance with Deep Learning"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-7894-099X","authenticated-orcid":false,"given":"Pedro","family":"Franco-Gon\u00e7alo","sequence":"first","affiliation":[{"name":"Department of Veterinary Science, University of Tr\u00e1s-os-Montes and Alto Douro (UTAD), 5000-801 Vila Real, Portugal"},{"name":"Veterinary and Animal Science Research Centre (CECAV), University of Tr\u00e1s-os-Montes and Alto Douro (UTAD), 5000-801 Vila Real, Portugal"},{"name":"Associate Laboratory for Animal and Veterinary Sciences (AL4AnimalS), 5000-801 Vila Real, Portugal"}]},{"given":"Pedro","family":"Leite","sequence":"additional","affiliation":[{"name":"Neadvance Machine Vision SA, 4705-002 Sequeira, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9842-1759","authenticated-orcid":false,"given":"Sofia","family":"Alves-Pimenta","sequence":"additional","affiliation":[{"name":"Veterinary and Animal Science Research Centre (CECAV), University of Tr\u00e1s-os-Montes and Alto Douro (UTAD), 5000-801 Vila Real, Portugal"},{"name":"Associate Laboratory for Animal and Veterinary Sciences (AL4AnimalS), 5000-801 Vila Real, Portugal"},{"name":"Department of Animal Science, University of Tr\u00e1s-os-Montes and Alto Douro (UTAD), 5000-801 Vila Real, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4879-8624","authenticated-orcid":false,"given":"Bruno","family":"Cola\u00e7o","sequence":"additional","affiliation":[{"name":"Veterinary and Animal Science Research Centre (CECAV), University of Tr\u00e1s-os-Montes and Alto Douro (UTAD), 5000-801 Vila Real, Portugal"},{"name":"Associate Laboratory for Animal and Veterinary Sciences (AL4AnimalS), 5000-801 Vila Real, Portugal"},{"name":"Department of Animal Science, University of Tr\u00e1s-os-Montes and Alto Douro (UTAD), 5000-801 Vila Real, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6573-7511","authenticated-orcid":false,"given":"Lio","family":"Gon\u00e7alves","sequence":"additional","affiliation":[{"name":"School of Science and Technology, University of Tr\u00e1s-os-Montes and Alto Douro (UTAD), 5000-801 Vila Real, Portugal"},{"name":"Department of Engineering, University of Tr\u00e1s-os-Montes and Alto Douro (UTAD), 5000-801 Vila Real, Portugal"},{"name":"Institute for Systems and Computer Engineering (INESC-TEC), Technology and Science, 4200-465 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3747-6577","authenticated-orcid":false,"given":"V\u00edtor","family":"Filipe","sequence":"additional","affiliation":[{"name":"School of Science and Technology, University of Tr\u00e1s-os-Montes and Alto Douro (UTAD), 5000-801 Vila Real, Portugal"},{"name":"Department of Engineering, University of Tr\u00e1s-os-Montes and Alto Douro (UTAD), 5000-801 Vila Real, Portugal"},{"name":"Institute for Systems and Computer Engineering (INESC-TEC), Technology and Science, 4200-465 Porto, Portugal"}]},{"given":"Fintan","family":"McEvoy","sequence":"additional","affiliation":[{"name":"Department of Veterinary Clinical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, 1165 Copenhagen, Denmark"}]},{"given":"Manuel","family":"Ferreira","sequence":"additional","affiliation":[{"name":"Neadvance Machine Vision SA, 4705-002 Sequeira, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0464-7771","authenticated-orcid":false,"given":"M\u00e1rio","family":"Ginja","sequence":"additional","affiliation":[{"name":"Department of Veterinary Science, University of Tr\u00e1s-os-Montes and Alto Douro (UTAD), 5000-801 Vila Real, Portugal"},{"name":"Veterinary and Animal Science Research Centre (CECAV), University of Tr\u00e1s-os-Montes and Alto Douro (UTAD), 5000-801 Vila Real, Portugal"},{"name":"Associate Laboratory for Animal and Veterinary Sciences (AL4AnimalS), 5000-801 Vila Real, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2025,5,3]]},"reference":[{"key":"ref_1","first-page":"181","article-title":"Diagnosis, Prevention, and Management of Canine Hip Dysplasia: A Review","volume":"6","author":"Lopez","year":"2015","journal-title":"Vet. 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