Intermediate-Term Outcomes of a Third-Generation, 2-Component Total Ankle Prosthesis.

Area of Science:

• Orthopedic surgery
• Biomedical engineering
• Podiatric medicine

Background:

• Previous INBONE I and II tibial stems demonstrated favorable short-term outcomes.
• The INBONE-II talus component showed reduced reoperation and failure rates compared to its predecessor.
• This study evaluates the mid-term performance of a third-generation, two-component total ankle prosthesis.

Purpose of the Study:

• To assess the mid-term outcomes (5-9 years) of the third-generation INBONE total ankle prosthesis.
• To evaluate both the tibial and talar components of the prosthesis.
• To analyze survivorship, component alignment, and complication rates.

Main Methods:

• Retrospective case series of 15 primary total ankle arthroplasties (TAA) using the INBONE-II prosthesis.
• Mean follow-up of 85 months (range, 61-113 months).
• Radiographic assessment of coronal and sagittal tibiotalar alignment; review of medical records for revisions, reoperations, and complications.

Main Results:

• Prosthesis survivorship was 93.7% at a mean of 85 months.
• Coronal and sagittal tibiotalar alignment was maintained from early postoperative to mid-term follow-up.
• One early component revision (6.7%) and four non-implant-related revisions (26.7%) occurred; 33.3% of ankles experienced complications.

Conclusions:

• This is the first mid-term follow-up study of this third-generation, two-component total ankle prosthesis.
• High survivorship and maintained alignment were observed, with a low incidence of major complications.
• Lateral gutter impingement was the most frequent complication, driving nonrevisional reoperations.