Analyzing Learning Curve Effects: Total Ankle Replacement Design Switch and Long-Term Survival

Area of Science:

• Orthopedic Surgery
• Biomedical Engineering
• Medical Statistics

Background:

• The learning curve for total ankle replacement (TAR) is often considered around 30 cases for short-to-mid-term outcomes.
• The impact of surgeon experience on the long-term survival of TAR remains largely unexamined.
• Understanding the learning curve is crucial for optimizing patient outcomes and surgical training in TAR.

Purpose of the Study:

• To evaluate the long-term survival rates of total ankle replacement (TAR) in relation to surgeon experience.
• To identify the presence and impact of a learning curve on perioperative complications in TAR.
• To assess the association between perioperative complications, operation time, and long-term TAR survival.

Main Methods:

• Retrospective analysis of 77 consecutive total ankle replacements performed by a single orthopedic surgeon.
• Kaplan-Meier and Competing Risk Analyses were used to compare long-term survival between early (cases 1-30) and later (cases 31-77) procedures.
• Moving Average Method with LOESS regression assessed the learning curve for perioperative complications, while Cox proportional hazard models analyzed survival associations.

Main Results:

• No significant difference in 10- or 15-year survival rates was observed between the initial 30 cases and subsequent cases.
• The learning curve analysis revealed a significant decreasing trend in perioperative osseous complications around 33 procedures, particularly after a prosthesis design switch.
• Neither operating time nor perioperative fractures were significantly associated with long-term survival.

Conclusions:

• Surgeons should acknowledge a learning curve when adopting arthroplasty procedures like TAR.
• A learning curve for perioperative osseous complications in TAR was confirmed at approximately 33 procedures, especially following a prosthesis design change.
• The identified learning curve for complications did not negatively impact the long-term survival rates of total ankle replacement.