Three-dimensionally printed vertebrae with different bone densities for surgical training

Area of Science:

• Biomedical Engineering
• Orthopedic Surgery
• Medical Simulation

Background:

• Developing realistic surgical simulators is crucial for training orthopedic surgeons.
• Current simulation models may not accurately replicate the haptic feedback of diverse bone densities encountered in spinal surgery.

Purpose of the Study:

• To evaluate the haptic realism of 3D-printed vertebrae for simulating posterior pedicle screw placement and decompression surgery.
• To assess whether 3D-printed vertebrae can mimic properties ranging from normal to osteoporotic bone.

Main Methods:

• A parameterizable vertebra model was created to adjust cortical and cancellous bone thickness.
• Five types of L3 vertebrae were 3D-printed and assessed by four spine surgeons for haptic feedback during simulated surgical steps.
• Torque measurements were recorded during pedicle screw insertion into the 3D-printed vertebrae.

Main Results:

• 3D-printed vertebrae received varied haptic assessment scores, with some simulating osteoporotic, normal, and hard bone properties.
• Surgeons rated specific 3D-printed vertebrae (α, γ1, γ2) as more realistic than commercially available Sawbones vertebrae.
• Mean pedicle screw insertion torques varied significantly across the different 3D-printed vertebra types and Sawbones.

Conclusions:

• 3D-printed vertebrae offer a haptically and biomechanically realistic simulation for posterior spinal procedures.
• This technology surpasses current commercial models (Sawbones) in realism for surgical simulation.
• 3D-printed vertebrae enable bone density-specific surgical training and hold potential for patient-specific preoperative simulation.