Application of deep learning algorithms in classification and localization of implant cutout for the postoperative hip

Skeletal Radiol. 2025 Jan;54(1):67-75. doi: 10.1007/s00256-024-04692-6. Epub 2024 May 21.

Abstract

Objective: This study aims to explore the feasibility of employing convolutional neural networks for detecting and localizing implant cutouts on anteroposterior pelvic radiographs.

Materials and methods: The research involves the development of two Deep Learning models. Initially, a model was created for image-level classification of implant cutouts using 40191 pelvic radiographs obtained from a single institution. The radiographs were partitioned into training, validation, and hold-out test datasets in a 6/2/2 ratio. Performance metrics including the area under the receiver operator characteristics curve (AUROC), sensitivity, and specificity were calculated using the test dataset. Additionally, a second object detection model was trained to localize implant cutouts within the same dataset. Bounding box visualizations were generated on images predicted as cutout-positive by the classification model in the test dataset, serving as an adjunct for assessing algorithm validity.

Results: The classification model had an accuracy of 99.7%, sensitivity of 84.6%, specificity of 99.8%, AUROC of 0.998 (95% CI: 0.996, 0.999) and AUPRC of 0.774 (95% CI: 0.646, 0.880). From the pelvic radiographs predicted as cutout-positive, the object detection model could achieve 95.5% localization accuracy on true positive images, but falsely generated 14 results from the 15 false-positive predictions.

Conclusion: The classification model showed fair accuracy for detection of implant cutouts, while the object detection model effectively localized cutout. This serves as proof of concept of using a deep learning-based approach for classification and localization of implant cutouts from pelvic radiographs.

Keywords: Artificial intelligence; Deep learning; Implant cutout; Orthopaedic implant; Pelvis radiograph.

MeSH terms

  • Aged
  • Algorithms
  • Arthroplasty, Replacement, Hip
  • Deep Learning*
  • Feasibility Studies
  • Female
  • Hip Prosthesis*
  • Humans
  • Male
  • Middle Aged
  • Prosthesis Failure
  • Radiographic Image Interpretation, Computer-Assisted / methods
  • Retrospective Studies
  • Sensitivity and Specificity*