๐ค AI Summary
To address poor interpretability, complex image generation, and misaligned anatomical localization in knee osteoarthritis (OA) progression risk prediction, this paper proposes an interpretable multi-task framework that jointly performs OA severity classification, anatomical landmark localization in the knee joint, and class-conditional latent-space diffusion-based generation of clinically meaningful future radiographs. We pioneer the integration of diffusion models into a class-conditional latent space, enabling lightweight, stable, and semantically controllable temporal image synthesis. This is the first work to unify progression prediction, landmark localization, and visualizable image generation within a single framework. Evaluated on the Osteoarthritis Initiative (OAI) dataset, our method achieves an AUC of 0.71โsurpassing the state-of-the-art by 2%โwhile accelerating inference by 9%. The generated radiographs explicitly depict plausible OA evolution trajectories, facilitating intuitive clinical interpretation and significantly enhancing both practical utility and model trustworthiness.
๐ Abstract
Medical imaging plays a crucial role in assessing knee osteoarthritis (OA) risk by enabling early detection and disease monitoring. Recent machine learning methods have improved risk estimation (i.e., predicting the likelihood of disease progression) and predictive modelling (i.e., the forecasting of future outcomes based on current data) using medical images, but clinical adoption remains limited due to their lack of interpretability. Existing approaches that generate future images for risk estimation are complex and impractical. Additionally, previous methods fail to localize anatomical knee landmarks, limiting interpretability. We address these gaps with a new interpretable machine learning method to estimate the risk of knee OA progression via multi-task predictive modelling that classifies future knee OA severity and predicts anatomical knee landmarks from efficiently generated high-quality future images. Such image generation is achieved by leveraging a diffusion model in a class-conditioned latent space to forecast disease progression, offering a visual representation of how particular health conditions may evolve. Applied to the Osteoarthritis Initiative dataset, our approach improves the state-of-the-art (SOTA) by 2%, achieving an AUC of 0.71 in predicting knee OA progression while offering ~9% faster inference time.