APPLICATION OF DYNAMIC RADIOGRAPHY TECHNIQUES IN KNEE JOINT EXAMINATION: AN EXPLORATORY STUDY

Abstract

The knee joint is a crucial musculoskeletal area frequently affected by injury and degeneration, significantly impacting quality of life and increasing global healthcare costs. Although conventional radiography remains the diagnostic standard, this modality has limitations in capturing functional and dynamic features of knee joint pathology, such as patellofemoral instability or impaired mechanics during movement, a weakness that is increasingly relevant given the increasing prevalence of degenerative knee joint diseases (estimated at over 30% in the elderly population) and the high rate of sports injuries. This research gap highlights the urgent need for more informative imaging techniques, given the limited number of studies exploring the potential of dynamic radiography for visualizing the complex interactions between knee joint structures during functional loading. This study aimed to comprehensively investigate the feasibility and effectiveness of applying dynamic radiographic techniques, specifically fluoroscopy with functional loading, in the anatomical and biomechanical evaluation of the knee joint in patients with pain and instability, based on a theoretical framework of musculoskeletal biomechanics that emphasizes the importance of integrated movement analysis, with the primary hypothesis being that dynamic radiography is capable of providing additional diagnostic information not obtainable from conventional radiographic statistics. Using a quantitative and qualitative exploratory study design with a cross-sectional approach, 50 adult patients (mean age 45.2 ± 12.5 years, 60% women) with chronic knee pain or a history of instability were recruited through convenience sampling, undergoing examination using a high-resolution digital fluoroscopy system with controlled axial loading and recorded flexion-extension movements. The validity and reliability of dynamic image interpretation were evaluated by two experienced musculoskeletal radiologists, while data-reliability analysis included qualitative descriptions of pathological findings and quantitative analysis of biomechanical parameters. Results showed that dynamic radiography was significantly superior in identifying biomechanical abnormalities compared to statistical radiography, with 78% of patients demonstrating pathological deviations not visible on statistical examination (p < 0.001, Cohen's d = 0.85), including the detection of latent patellofemoral instability in 45% of patients and evidence of abnormal femoral rollback in 30%. Secondary analysis found a strong positive correlation (r = 0.72, p < 0.01) between dynamic tibiofemoral joint space narrowing and pain severity, as well as the unexpected finding of visualization of dynamic meniscus-cartilage interactions. In conclusion, the application of dynamic radiography is effective in providing an in-depth understanding of the biomechanical pathology underlying knee complaints, contributing to the literature by demonstrating the diagnostic value of functional modalities, and providing practical applications for clinicians in optimizing diagnosis and management. Validation in a larger cohort and evaluation of its clinical impact are recommended.