Inter‐Rater Reliability of Video Based Sonographic Assessment of Lower Extremity Tendon and Fascia Abnormalities

ABSTRACT Introduction Ultrasound is a sensitive and specific tool for identifying structural changes in tendinopathy and fasciopathy. While prior studies have assessed inter‐rater reliability using static images with mixed results, none have examined reliability using retrospective sonographic video review. This study aims to evaluate the inter‐rater reliability of dynamic ultrasound video interpretation of the patellar tendon, Achilles tendon, and plantar fascia. Methods Forty collegiate athletes from a prospective, observational cohort underwent standardized ultrasound scans of bilateral patellar and Achilles tendons, and plantar fasciae. Four reviewers with varying levels of ultrasound experience assessed the videos for hypoechogenicity, thickening, and neovascularity using binary (yes/no) responses. Inter‐rater reliability was measured using kappa statistics. Results Agreement between the trained and moderately trained reviewers was near perfect ( κ = 0.947–1.00). Agreement between the trained and minimally trained reviewers ranged from 0.490 to 0.787, and between the trained and untrained reviewers from 0.490 to 0.810. Conclusion Moderate to near perfect inter‐reliability was achieved in identifying tendinous abnormalities. Reviewer experience significantly influences diagnostic agreement, suggesting that training level is an important consideration in clinical and research ultrasound interpretation.