Osteolysis After HINTEGRA Total Ankle Replacement: Radiographic Patterns, Alignment Associations, and Long-Term Outcomes.

Background: Total ankle replacement (TAR) is a surgical option for patients with ankle arthritis who have failed conservative measures. Newer implants have markedly improved; however, osteolysis causing aseptic loosening continues to be a main cause of TAR failure. The objective of this study was to review the HINTEGRA TAR experience at a single institution specifically evaluating the presence and outcomes of osteolysis.

Methods: Retrospective study including all HINTEGRA TARs completed by 1 experienced foot and ankle surgeon from 2006 to 2014. Radiographs were reviewed, assessing for implant positioning, presence, location, and progression of cysts as well as relationship between osteolysis with reoperations and revisions.

Results: Fifty-one TARs were identified with radiographic follow-up of 5.8 ± 3.5 years. Eighty-four cysts were detected in 37 patients, with increasing number and size of cysts being correlated to length of time from surgery. The most common location was the posterior tibia. Thirteen patients had enlarging cysts identified over time, with the lateral malleolus being the most common location. Seven patients met criteria for malaligned prosthesis, 12 patients required a reoperation, and 2 patients experienced implant failure.

Conclusion: Osteolysis is a very common finding after TAR using the HINTEGRA prosthesis, specifically on long-term radiographic follow-up. Progressive cysts and prosthesis coronal malalignment appear to be risk factors for developing osteolysis, prosthesis loosening, and reoperation. Most cysts did not result in clinical failure, but progressive lesions identified beyond 1 year warrant closer monitoring. This study also shows excellent and reliable outcomes of the HINTEGRA TAR compared with designer surgeons with acceptable complication and revision rates.

Level of evidence: Level IV, Case series.