A Low-Cost, Reusable, Ballistic Gelatin Ultrasound Phantom for Simulation of Glenohumeral Intraarticular Injections.

Abstract

Deliberate practice of invasive procedures on simulation phantoms has been recommended to teach trainees. For many departments, these task trainers can be prohibitively expensive. Sometimes, phantoms for specialized procedures are not commercially available at all. There are currently are no commercially available simulation phantoms for the purpose of ultrasound (US)-guided glenohumeral joint injection. The objective was to create a low-cost, reusable, homemade simulation phantom for US-guided glenohumeral joint injection using easily obtainable materials as well as to determine whether use of such a homemade model by novice learners is associated with increased self-reported comfort level and knowledge of the procedure. Fourth-year emergency medicine-bound medical students and PGY-1 residents were asked to participate in a hands-on 30-minute training session for US-guided glenohumeral joint injection using a homemade simulation phantom. Participants were assessed by pre- and postintervention survey of self-reported comfort levels with the procedure. Outcomes were measured on modified global rating scale (GRS; minimum= 1, maximum= 7). The primary outcome was learner comfort with US-guided glenohumeral joint injection. Secondary outcomes were comfort level in obtaining adequate US image and identifying landmarks of the glenohumeral joint as well as likelihood to perform US-guided injection of the glenohumeral joint in a clinical setting. In the primary outcome, mean GRS scores in 13 participants for comfort with the procedure increased from 2.7 to 5.0 (p<0.01) after intervention. Mean GRS for knowledge of anatomy increased from 2.8 to 5.4 (p<0.01) and mean GRS for comfort in image acquisition increased from 2.8 to 5.3 (p<0.01). Mean GRS for likelihood to perform the procedure trended toward increase from 4.6 to 5.5 (p=0.25). Use of a homemade, low-cost, ballistic gelatin US phantom for simulation of glenohumeral intraarticular injection was associated with increased learner comfort with the procedure.