Validation of Pre-operative Templating for Total Disc Replacement Surgery

Area of Science:

• Spinal surgery
• Biomechanical engineering
• Orthopedic research

Background:

• Adjacent segment disease is a risk after total disc replacement (TDR) with limited postoperative range of motion (ROM).
• Patient anatomy and implant parameters significantly influence ROM and clinical outcomes following TDR.

Purpose of the Study:

• Validate patient-specific finite element (FE) templating for predicting postoperative ROM.
• Determine optimal implant parameters (size, height, configuration, location) to maximize ROM.
• Correlate achieved ROM with clinical outcomes using Oswestry Disability Index (ODI).

Main Methods:

• Constructed 3D FE models from preoperative CT scans for 17 patients with 22 ProDisc-L devices.
• Utilized FE templating to identify optimal implant size and location, predicting ROM.
• Measured actual postoperative ROM from radiographs and compared it with predicted values.

Main Results:

• FE analysis showed no significant difference between predicted and actual postoperative ROM.
• Computational templating identified potential for significantly greater ROM compared to achieved ROM.
• Optimal implant selection could have improved ROM by an average of 1.2° (12%).

Conclusions:

• FE analysis accurately predicts ROM after ProDisc-L implantation.
• FE templating can guide optimal implant selection to enhance ROM and clinical success.