The FDA updated its safety communication regarding the Hintermann Series H3 Total Ankle Replacement (TAR) System, manufactured by DT MedTech LLC of Towson, Maryland. The agency stated it is now recommending that surgeons and patients “consider using other available treatment options where possible.” That language represents a meaningful escalation from the FDA’s two earlier communications on the device, issued in February 2024 and October 2025, which flagged higher-than-expected failure rates but stopped short of recommending alternatives.

The H3 TAR system is a three-component, mobile-bearing ankle prosthesis consisting of a metal tibial plate, a metal talar component, and a mobile polyethylene (plastic) bearing that sits between them. It is indicated for use as a non-cemented artificial ankle joint to replace a painful arthritic ankle caused by osteoarthritis, post-traumatic osteoarthritis, or inflammatory arthritis. The FDA approved the device in 2019, making it only the second total ankle replacement to receive full FDA premarket approval following the Scandinavian Total Ankle Replacement (STAR) system cleared in 2009.

The updated safety communication draws on three independent data sources, and the findings from each tell a consistent story. The manufacturer’s own FDA-mandated post-approval study — a prospective cohort tracking 280 patients from the original premarket clinical trials — found that 31.8% of patients required revision surgery within 10 years. That includes revisions of both the metal and polyethylene components. Even when only metal component revisions are counted, the rate was 14.9% at 10 years, more than double the 6.5% rate observed at 5 years. Notably, the FDA flagged significant data quality concerns with the study: 55.7% of patients were lost to follow-up or had missing data at the 10-year mark, a limitation that could make the actual revision rate either higher or lower than the reported figure.

The most striking data, however, came from outside the manufacturer’s study. The Australian Orthopaedic Association’s National Joint Replacement Registry analyzed 573 H3 TAR implants alongside 4,806 other total ankle replacements performed in Australia through 2024. The 15-year cumulative revision rate for the H3 was 25.7%, compared to 15.2% for all other total ankle devices — nearly 70% higher. After adjusting for patient age and sex, the H3 carried a statistically significant hazard ratio of 1.93 for revision compared to other devices, meaning patients with the H3 were roughly twice as likely to need additional surgery. The United Kingdom’s National Joint Registry reported a 9.5% revision rate for the H3 at 10 years, though the UK registry acknowledged that up to one-third of ankle revisions in Britain go unreported, suggesting the actual rate may be higher.

Polyethylene fracture — breakage of the plastic bearing component — emerged as a particularly concerning failure mode. The Australian registry data showed the 10-year cumulative incidence of revision due to polyethylene fracture was approximately four times higher for the H3 than for all other ankle replacement devices. While loosening was the most common reason for H3 revision overall at 25%, polyethylene breakage was the second most common at 16.7%, followed by infection and instability at 10.2% each. For comparison, among all other total ankle devices, polyethylene breakage ranked fifth as a reason for revision, accounting for only 6.3% of cases.

The regulatory response has been swift and international. Australia’s Therapeutic Goods Administration went further than the FDA, issuing a market action on February 12, 2026 and banning the sale and distribution of the H3 TAR system in Australia entirely as of May 5, 2026. The device remains available in the United States, but the FDA’s updated recommendation to consider alternatives is the strongest language the agency has used short of ordering a market withdrawal.

The FDA’s safety communication does not recommend removal of functioning H3 implants. Patients whose devices are working well and who have no new or worsening symptoms should continue with their existing follow-up schedules. However, the FDA does recommend close monitoring for loosening, polyethylene fracture, and wear-related complications, and notes that CT imaging may be needed because the signs of plastic component fracture can be subtle even on standard X-rays. For adjusters and case managers overseeing claims involving workers with H3 implants already in place, this means ongoing surveillance costs and the potential for future revision surgery should be factored into reserve estimates.

The FDA has stated it will continue reviewing data from all available sources and will keep the public informed if significant new information emerges. Given the trajectory of the agency’s communications — from alerting, to updating, to now recommending alternatives — further action remains a possibility. Stakeholders with open claims involving the H3 TAR system, or with pending treatment authorizations for total ankle replacement, should be tracking this issue closely.