Deep Learning Analysis of Routine Preoperative Knee Radiographs for Five-Year Prediction of Contralateral Arthroplasty.
Authors
Affiliations (8)
Affiliations (8)
- School of Medicine, Baylor College of Medicine, 1 Baylor Plaza, Houston, TX 77030, USA.
- College of Natural Sciences, The University of Texas at Austin, Austin, TX 78712, USA.
- Department of Biomedical Sciences, Texas A&M University, College Station, TX 77843, USA.
- College of Engineering and Applied Sciences, University of Cincinnati, Cincinnati, OH 45221, USA.
- Massachusetts Eye and Ear, Department of Ophthalmology, Harvard Medical School, Boston, MA 02114, USA.
- Department of Computer Science, University of Nevada, Reno, NV 89557, USA.
- Department of Computer Science, Cornell University, Ithaca, NY 14853, USA.
- Department of Orthopaedic Surgery, Baylor University Medical Center, Dallas, TX 75246, USA.
Abstract
<b>Background</b>: Before unilateral total knee arthroplasty (TKA), the contralateral radiograph is reduced to a Kellgren-Lawrence grade. We asked what the image adds, what the model reads, and how many views are needed. <b>Methods</b>: A multi-view DenseNet121 survival network predicted 5-year contralateral arthroplasty from routine radiographs, against Cox models over 11 clinical variables with and without the dataset-inferred grade, on a once-read test split. <b>Results</b>: In 741 test patients (106 events), the primary contrast put the combined model's 5-year censoring-weighted AUROC at 0.844 against the clinical model's 0.680 among the 740 patients that received both scores (difference 0.164, 0.087 to 0.240). Post hoc, a frontal radiograph alone read 0.837, matching the multi-view arms because 56.6% had only a frontal film; withholding lateral and sunrise views cost 0.078 (0.012 to 0.142) in the 315 patients with both. Grad-CAM put 37.8% of attribution in a joint region covering 25.0%; occluding it left 0.800. <b>Conclusions</b>: The preoperative radiograph adds prognostic information beyond the clinical record. Exploratory analyses place almost all of it in one frontal film and beyond an automated grade, not a radiologist's read. These internal analyses require external validation.