A NexGen knee implant failure risk was identified years before the product was removed from UK hospitals, according to a BBC File on 4 investigation. The implant, fitted in more than 10,000 knee replacement surgeries, has left hundreds of patients in severe pain, immobile, or dependent on powerful painkillers — with many requiring costly corrective surgery.
The faulty component, known as the “stemmed option tibial component” or “tibial tray,” was marketed by US manufacturer Zimmer Biomet from 2012. It lacked a plastic layer present in earlier, more reliable models. Surgeons now say the company took too long to act on mounting evidence of failures.
Patients Left in Pain and Facing Multiple Operations
Southampton patient Debbie Booker underwent knee replacement surgery in 2016, but within a year, her implant began to slip, causing severe bone damage. She became dependent on fentanyl and morphine for pain relief and now walks with a limp, awaiting a hip replacement.
Another patient, “Diana,” had a similar implant fitted in 2021 that left her “virtually immobile.” Her consultant told her that every time she stood up, she was “standing on a broken leg.”
Both women later learned their implants had higher-than-average failure rates, forcing them to undergo revision surgery.
Early Warnings Ignored
Concerns about the implant were first flagged in 2014 by the UK’s National Joint Registry (NJR) and again in 2016 by Irish surgeon Professor Eric Masterson. He reported an alarming rise in revision surgeries after using NexGen implants, but says Zimmer Biomet dismissed his warnings and selectively connected him only with surgeons satisfied with the product.
British surgeon Professor Leila Biant told the BBC she and colleagues raised similar concerns in 2017, but the company showed “reluctance to acknowledge a problem” until forced to act.
Withdrawal and Failure Rates
In 2022, the NJR found NexGen recipients were nearly twice as likely to require corrective surgery compared with average knee implant patients. That same year, Zimmer Biomet recalled remaining stock from the UK market.
Peer-reviewed studies estimate the tibial tray failure rate at between 6% and 19%, well above the expected level.
High Financial and Medical Costs
Each revision surgery costs the NHS between £10,000 and £30,000, with longer hospital stays and more intensive care needed. The total bill is expected to reach millions of pounds.
Zimmer Biomet has told sales staff it will not cover diagnostic, follow-up, or revision costs upfront. NHS England confirmed it is reviewing the case.
In a statement, Zimmer Biomet said patient safety is its “top priority” and that it acts in line with regulations when new data emerges.
