A Novel Mixed-reality Simulator for Training Metacarpal Fracture Reduction and Kirschner Wire Fixation

Area of Science:

• Orthopedic Surgery
• Medical Simulation
• 3D Printing Technology

Background:

• Metacarpal fracture reduction and Kirschner wire (K-wire) fixation are crucial hand surgery skills that present a steep learning curve for trainees.
• Extended reality (XR) surgical simulation has demonstrated efficacy in enhancing intraoperative performance across various surgical disciplines.

Purpose of the Study:

• To develop and validate a mixed reality-integrated hand model simulator for training plastic surgery residents in metacarpal fracture reduction and fixation.

Main Methods:

• A 3D-printed hand model was created using patient imaging data, incorporating wire channels and sensors for real-time tracking.
• Fracture bridges were integrated for reproducible fracture introduction, and the model was cast in silicone for realistic surface anatomy.
• A 3D-printed K-wire driver and tracking application were developed to monitor hand model, fracture, and driver positioning during simulated procedures.

Main Results:

• The 3D printing accuracy demonstrated a Hausdorff distance error below 0.13 mm, with a target registration error for fractures under 1 mm.
• The simulator achieved high median scores (5/5) for anatomical accuracy, clinical comparability, fracture reduction realism, and perceived training value.
• Percutaneous entry, K-wire placement, fluoroscopy, and training realism received median scores of 4/5, with unanimous recommendation by participants.

Conclusions:

• A validated mixed reality-integrated hand model simulator has been developed for plastic surgery resident training.
• The simulator effectively trains metacarpal fracture reduction and K-wire fixation, offering a realistic and valuable learning tool.