Failure modes of current total ankle replacement systems.

Area of Science:

• Orthopedic surgery
• Biomedical engineering
• Medical device evaluation

Background:

• Ankle fusion, while common, presents significant functional limitations and complications.
• Early total ankle replacements, particularly fixed-bearing designs, demonstrated poor long-term outcomes.
• Existing fixed-bearing total ankle prostheses often underperform compared to fusion or earlier designs.

Purpose of the Study:

• To describe the methodology for evaluating total ankle replacements.
• To compare the efficacy and safety of ankle fusion versus total ankle joint replacement.
• To identify current advancements in total ankle replacement technology.

Main Methods:

• Review of existing literature and clinical data on ankle fusion and total ankle replacement.
• Analysis of outcomes for early and current fixed-bearing total ankle prostheses.
• Evaluation of mobile-bearing total ankle replacement designs, including clinical trial data.

Main Results:

• Ankle fusion is associated with reduced ankle functionality and notable complications.
• Early fixed-bearing total ankle replacements were largely unsuccessful and discontinued.
• Current fixed-bearing total ankle designs show inferior or equivalent results to fusion.
• Mobile-bearing total ankle devices demonstrate reasonable safety and effectiveness.

Conclusions:

• Mobile-bearing total ankle replacements represent a safer and more effective alternative to fusion and fixed-bearing designs.
• The STAR (Scandinavian Total Ankle Replacement) mobile-bearing device has undergone rigorous evaluation and is FDA-approved.
• Continued evaluation and development of mobile-bearing total ankle technology are warranted.