Design and validation of a simulator for equine joint injections

Joint injections are commonly used in equine practice for diagnosis and treatment of joint disorders. Performing joint injections is hence an essential skill for equine practitioners. However, opportunities for veterinary students to practice this skill are often scarce in veterinary curricula. The aim of this study was to design and validate an equine joint injection simulator. We hypothesized that the simulator will enhance student ability and confidence in performing joint injections. The simulator was constructed around an equine forelimb skeleton with soft tissues rebuilt using building foam and rubber bands. An electrical circuit including a buzzer, a battery, wire wool in the joints, and a hypodermic needle at the end of the cable was incorporated. If the students placed the needle into the joint correctly, instant auditory feedback was provided by the buzzer. To validate the simulator, 45 veterinary students were allocated to three groups: cadaver limb, textbook, or simulator. Students' ability to perform joint injections was tested and students' opinions were evaluated with a questionnaire. The proportion of students performing a metacarpophalangeal (MCP) joint injection correctly was significantly higher in the cadaver (93%) and simulator (76%) groups compared to the textbook group (50%). There was no significant difference between groups for performing a distal interphalangeal (DIP) joint injection correctly. Students rated the learning experience with the cadaver and simulator group high and with the textbook group low. The joint injection simulator represents an affordable teaching aid that allows students to repeatedly practice this skill in their own time with immediate feedback.