Tri-component, mobile bearing, total ankle replacement: mid-term functional outcome and survival

Area of Science:

• Orthopedic Surgery
• Biomedical Engineering
• Reconstructive Surgery

Background:

• First-generation cemented, highly constrained total ankle replacements had high failure rates.
• Tri-component, mobile bearing, uncemented total ankle replacements were developed as an alternative.
• Assessing the long-term outcomes of these newer implants is crucial for patient care.

Purpose of the Study:

• To evaluate the functional and radiographic outcomes of tri-component, mobile bearing, uncemented total ankle replacements.
• To determine the survival rate and identify failure modes in a retrospective patient cohort.
• To assess the efficacy of these implants in improving patient function.

Main Methods:

• Retrospective study of 30 primary total ankle replacements in 29 patients.
• Follow-up for up to 13 years (mean 5.1 years).
• Failure defined as revision or conversion to arthrodesis; Kaplan-Meier survival analysis used.

Main Results:

• Mean American Orthopaedic Foot and Ankle Society score was 81 at 1 year postoperatively.
• Three patients (2 revisions, 1 arthrodesis) experienced failure, all due to malpositioned talar implants.
• Kaplan-Meier analysis indicated an 87.6% 5-year survival rate for the total ankle replacements.

Conclusions:

• Uncemented, mobile bearing total ankle replacements demonstrate a favorable 5-year survival rate.
• Accurate talar component placement is critical to prevent early revision and improve outcomes.
• These implants offer a viable option for patients requiring total ankle replacement.