Educational Impact of a 30-Minute Ultrasound Training Lecture on Medial Meniscus Extrusion Measurements: A Pilot Study of Intra- and Inter-rater Reliability Among Novice Students.

backgroundMedial meniscus extrusion (MME) is a pivotal biomarker for knee osteoarthritis progression. Although ultrasonography offers a dynamic and cost-effective MME assessment, its clinical utility is often limited by the perceived high barrier of examiner proficiency. This study evaluated the educational impact of a brief, standardized training session on the reliability of MME measurements obtained by novice physical therapy students compared to those obtained by an experienced physical therapist (PT).

methodsThe participants in this pilot study comprised eight healthy young adults (16 knees), one experienced PT (eight years of experience), and two third-year students (Students A and B) without prior MME measurement experience. The students attended a targeted 30-minute lecture on knee sonoanatomy and MME measurement protocols. MME was measured under weight-bearing (WB) and non-WB (NWB) conditions using a longitudinal scan directly beneath the medial collateral ligament. Reliability was assessed via intraclass correlation coefficients (ICC(1, 1) and ICC(2, 1)) and a Bland-Altman analysis.

resultsFollowing the 30-minute session, both students achieved moderate intra-rater reliability (ICC(1, 1): 0.693-0.705). Inter-rater agreement with the PT was highly inconsistent across conditions and individuals; for the WB condition, Student B demonstrated excellent agreement (ICC(2, 1): 0.895), whereas Student A demonstrated poor agreement (0.204). For the NWB condition, Student A showed moderate agreement (ICC(2, 1): 0.589), whereas Student B showed poor agreement (0.220). The Bland-Altman analysis identified a proportional bias only for Student A's intra-rater measurements (between the second and third trials) under the NWB condition. Random errors (minimal detectable change at 95% confidence level (MDC95)) were 0.34-0.50 mm for student intra-rater trials and 0.40-0.65 mm for inter-rater comparisons.

conclusionsA 30-minute educational intervention enabled novice physical therapy students to occasionally achieve expert-level reliability for specific conditions; however, it did not ensure consistent proficiency across different physical settings. The significant variability between the students and the presence of proportional bias in NWB measurements suggest that theoretical knowledge alone is insufficient to master the technical nuances of MME ultrasonography. These findings highlight the potential for ultrasound in clinical education while emphasizing the necessity of intensive hands-on training and feedback to bridge the gap between novice and expert performance.