Ultrasound assessment of Achilles enthesitis: a dedicated training program

To describe an intensive and multimodal ultrasound (US) training program focused on Achilles enthesitis and to illustrate the learning curve of trainees without experience.

Three medical students (trainees) and two rheumatologists experienced in musculoskeletal US (trainers) were involved in the training program, which encompassed one preliminary theoretical-practical meeting and five scanning sessions (two patients per session). The students and one expert performed the US examination of the Achilles enthesis bilaterally. The trainees acquired representative images and assessed the presence of Outcome Measures in Rheumatology (OMERACT) US abnormalities of enthesitis. The experts provided feedback addressing trainees' misinterpretations, and the quality of the acquired images was evaluated. A dedicated questionnaire was used to evaluate the students' confidence. After each session, five sets of static images (total=100 images of most commonly scanned entheses) were provided and scored by the students according to OMERACT US definitions. Total agreement and prevalence and bias adjusted kappa (PABAK) were used to evaluate the concordance between the trainees and the expert sonographer.

The total agreement and PABAK significantly improved between the first and fifth scanning sessions (76.2% versus 92.9%, p<0.01, and 0.5 versus 0.79, p<0.01) and between the first and fifth static image sets (64.5% versus 81.9%, p<0.01, and 0.29 versus 0.74, p<0.01). Image quality did not significantly improve (p=0.34). A significant increase in trainees' confidence was registered (p<0.01).

The described training program rapidly improved the students' performance in the US assessment of Achilles enthesitis, appearing to be an effective starting model for the future development of pathology-oriented teaching programs for the US in rheumatology.