To Infinity and Beyond

For surgeons and patients with end-stage arthritis, the choice between joint replacement and fusion isn’t always clear. A new study offers direct comparison by analyzing 100 INFINITY^® total ankle arthroplasty (TAA) patients (2008-2021) and 200 fusion patients (2013-2021), all with at least one year of follow up. Adults ≥19 years reported outcomes using the Ankle Osteoarthritis Scale, MODEMS, and SF-36, providing a head-to-head look at pain relief and long-term function. 

Results

Both groups improved at one year, but INFINITY TAA showed slightly better AOS improvement (pre-op 52.4 → 22.3) compared with fusion (55.3 → 26.0). At final follow-up, INFINITY patients had significantly lower (better) AOS scores, even after adjusting for baseline variables (mean difference -6.76; p=0.02). This advantage remained consistent when excluding early (one year) and late (9-14 years) follow-up data.

Revision rates

• Fusion: 3.5%

• Infinity TAA: 2%

Bottom line

Patients undergoing INFINITY TAA reported better long-term functional outcomes than those undergoing fusion, with comparable or lower revision rates.