A widely performed knee procedure known as partial meniscectomy may not deliver the benefits many patients expect, according to a new study out of the University of Helsinki.

In the 10-year clinical trial, researchers found that trimming a damaged meniscus — a procedure long believed to relieve pain—offers no real benefit over placebo surgery.

In fact, patients who had the operation fared worse over time, with more symptoms, poorer function, faster progression of osteoarthritis, and a greater likelihood of future surgery.

Partial meniscectomy is one of the most common orthopedic surgeries worldwide. While its use has declined in Finland in recent years, it remains a routine treatment in many countries.

The surgery has long been based on the idea that knee pain, especially on the inner side, is caused by a meniscus tear that can be fixed surgically. However, this assumption may not hold up.

“Such reasoning – assumption based on biological credibility – is still very common in medicine, but in this case, the assumption does not withstand critical examination. Based on current understanding, pain in various joints, such as the knee joint in this case, is related to degeneration brought about by aging,” says Raine Sihvonen, specialist in Orthopaedics and Traumatology and the other principal investigator of the FIDELITY study.

The Finnish Degenerative Meniscal Lesion Study (FIDELITY) included a sham surgery control group, which allowed researchers to directly compare outcomes against a placebo procedure.

Participants with degenerative meniscal tears were randomly assigned to receive either partial meniscectomy or sham surgery, and their progress was tracked for 10 years.

“Our findings suggest that this may be an example of what is known as a medical reversal, where broadly used therapy proves ineffective or even harmful,” said Teppo Järvinen, professor at the University of Helsinki and the principal investigator of the FIDELITY.

Earlier observational studies have already raised red flags about potential downsides of this surgery. These include a higher likelihood of arthroplasty or joint replacement surgery and a possible increase in complications after the procedure. However, observational data alone cannot prove cause and effect.

“Several randomized studies have already demonstrated that partial meniscectomy has not improved patients’ symptoms or function in the short (1-2 years) or medium (5 years) term. Regardless, the procedure has remained widely used in many countries,” says Doctoral Researcher and Specialist in Orthopaedics and Traumatology, Dr. Roope Kalske.

Despite mounting evidence, changes in clinical practice have been slow.

“For nearly a decade, many independent, non-orthopedic organizations providing clinical guidelines have recommended that the procedure should be discontinued. Still, for example, the American Academy of Orthopedic Surgeons (AAOS) and the British Association for Surgery of the Knee (BASK) have continued to endorse the surgery. This effectively illustrates how difficult it is to give up inefficient therapies,” Järvinen added.

The research was carried out across multiple hospitals, highlighting strong collaboration and patient commitment.

“The study conducted in five hospitals is an example of smooth multicenter collaboration, as well as the commitment of research patients to an interesting project. Of the original 146 participants, more than 90% took part in the final stage of the study,” says the research manager Pirjo Toivonen.

The Finnish Degenerative Meniscal Lesion Study FIDELITY is part of the broader work of the FICEBO research group in assessing the impact of surgical therapies. The project is a collaboration between the university hospitals of Helsinki, Kuopio and Turku, Hatanpää Hospital in Tampere, Hospital Nova in Jyväskylä, and the Finnish Institute for Health and Welfare.

University of Helsinki. (2026, May 6). Common knee surgery is found to be ineffective and may make things worse. ScienceDaily. Retrieved May 11, 2026, from www.sciencedaily.com/releases/2026/05/260505234603.htm