Abstract
Knee osteoarthritis is a progressive degenerative joint disorder characterized by cartilage deterioration, leading to pain, stiffness, reduced mobility, and functional impairment. Early detection and accurate grading of disease severity play a crucial role in effective clinical decision-making and prevention of further joint damage. Most existing deep learning approaches focus mainly on image-level classification using conventional CNN architectures and do not provide precise localization of the affected knee region, which is essential for clinical interpretation. In addition, limited research has explored unified object detection frameworks for simultaneous localization and severity grading of knee osteoarthritis. To address these limitations, this study proposes a YOLOv8-based deep learning framework for automated knee osteoarthritis detection and severity classification using radiographic X-ray images collected from a publicly available Kaggle dataset. The dataset is carefully annotated using Label Studio by marking the knee joint region and assigning five severity grades: Healthy, Doubtful, Minimal, Moderate, and Severe. The proposed model is trained using GPU acceleration to enhance computational efficiency and improve detection performance. Experimental evaluation is performed using standard metrics and the proposed system achieves a mAP@0.5 of 85.2%, demonstrating strong capability in both accurate localization and classification of knee osteoarthritis severity. It can be deployed in clinical decision support systems, radiology departments, and telemedicine platforms to enable rapid knee X-ray screening, providing radiologists, orthopaedic specialists, and physicians with an automated second opinion that reduces diagnostic time and human variability.References
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