Accuracy and Precision of Computer-Assisted Surgery Compared with Conventional Instrumentation for Total Ankle Arthroplasty

Computer-Assisted Surgery (CAS) systems enhance joint replacement accuracy. Total ankle arthroplasty (TAA) is a viable alternative to ankle fusion, but achieving precise implant alignment remains challenging due to limited surgical exposure and reliance on fluoroscopy. This study aimed to compare the accuracy of a conventional TAA technique using fluoroscopy to a previously developed CAS system. Twelve artificial ankle joints were used for the study. TAA was performed using conventional instrumentation and fluoroscopy. Bone resections were performed, and the resections were compared to the planned resections using 3D scanning and analysis software. Tibial and talar resections showed greater accuracy with the CAS system compared to the conventional technique. The conventional technique had larger deviations in tibial closed slope, tibial internal rotation, and talar slope. The conventional technique demonstrated acceptable accuracy, and was aligned with previous literature. However, the CAS system improved accuracy and precision, particularly by reducing outliers. Limitations of this study include the absence of soft tissues and limited surgeon variability with only one operator. Future studies should investigate surgeon variability, cadaveric models, and comparisons with patient-specific instrumentation (PSI) techniques. In conclusion, the conventional technique provides acceptable results, while the CAS system offers potential for enhanced accuracy and precision in TAA.