Context: Patients frequently present to the outpatient clinic, urgent care, or emergency department with a painful, swollen knee. Differentiating the underlying etiology can be a challenge for both medical students and seasoned clinicians alike. Because this scenario can represent a time-sensitive emergency, developing skills to diagnose the underlying cause quickly and accurately is essential for proper management, whether the patient would benefit from osteopathic manipulation, prompt administration of antibiotics, or a more invasive procedure like joint aspiration or surgery.
Objectives: The objectives are to determine the effects of a focused ultrasound training on first-year osteopathic medical students’ ability to identify normal sonographic anatomy of the anterior knee and to differentiate between three common pathologies: joint effusion, prepatellar bursitis, and cellulitis.
Methods: First-year osteopathic medical students voluntarily participated in this cross-sectional study. The study protocol included a focused ultrasound training (online materials, brief didactic and single hands-on sessions) followed by a hands-on assessment. A written test and 5-point Likert scale questionnaire were administered before and after the focused training. Nine weeks later, students completed a follow-up written test. The proportion of students who correctly identified common pathologies on written tests before (pretest) and after (posttest) training and on the follow-up written test were compared utilizing the Fisher’s exact test. A t test was utilized to compare data from the pretraining and posttraining questionnaires.
Results: Of 101 students completing the written pretest and pretraining questionnaire, 95 (94.1 %) completed the written posttest and posttraining questionnaire, and 84 (83.2 %) completed the follow-up written test. Students had limited previous experience with ultrasound; 90 (89.1 %) students had performed six or fewer ultrasound examinations before the focused ultrasound training. On written tests, students accurately identified joint effusion (22.8 % [23/101] pretest, 65.3 % [62/95] posttest, 33.3 % [28/84] follow-up test), prepatellar bursitis (14.9 % [15/101] pretest, 46.3 % [44/95] posttest, 36.9 % [31/84] follow-up test), and cellulitis (38.6 % [39/101] pretest, 90.5 % [86/95] posttest, 73.8 % [62/84] follow-up test). Differences were found between pretest and posttest for identification of all three pathologies (all p<0.001) and between the pretest and 9-week follow-up test for identification of prepatellar bursitis and cellulitis (both p≤0.001). For questionnaires, (where 1=strongly agree, 5=strongly disagree), the mean (standard deviation [SD]) confidence for correctly identifying normal sonographic anatomy of the anterior knee was 3.50 (1.01) at pretraining and 1.59 (0.72) at posttraining. Student confidence in the ability to differentiate joint effusion, prepatellar bursitis, and cellulitis utilizing ultrasound increased from 4.33 (0.78) at pretraining to 1.99 (0.78) at posttraining. For the hands-on assessment, 78.3 % (595 correct/760 aggregated responses) of the time students correctly identified specific sonographic landmarks of the anterior knee. When the evaluation combined real-time scanning with a prerecorded sonographic video clip of the anterior knee, 71.4 % (20/28) accurately identified joint effusion, 60.9 % (14/23) correctly diagnosed prepatellar bursitis, 93.3 % (28/30) recognized cellulitis, and 47.1 % (8/17) diagnosed the normal knee.
Conclusions: Our focused training was effective at immediately increasing basic knowledge, as well as confidence of first-year osteopathic medical students when assessing the anterior knee with point-of-care ultrasound. However, spaced repetition and deliberate practice may be useful for learning retention.