One of the world's most frequently performed orthopedic procedures appears to offer patients little benefit and may leave them worse off in the long run. A rigorous 10-year study has dealt a serious blow to the case for arthroscopic partial meniscectomy, a surgery that trims damaged meniscus tissue in the knee.
The Finnish Degenerative Meniscal Lesion Study, known as FIDELITY, followed patients who underwent the procedure and compared them directly to a control group that received sham surgery. The results were stark: after a decade, patients who actually had the surgery reported more knee symptoms, poorer function, greater progression of osteoarthritis, and were more likely to need additional knee operations. In other words, they fared worse than those who did not receive the actual treatment.
The study's design stands out for its rigor. Researchers randomly assigned 146 patients with degenerative meniscal tears to either real surgery or a placebo procedure, then tracked outcomes for 10 years. More than 90% of participants completed the final follow-up, lending credibility to the findings.
"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 principal investigator of the study.
The procedure has rested on a straightforward assumption: knee pain, particularly on the inner side, stems from a meniscus tear that surgery can fix. But that logic appears flawed. According to Raine Sihvonen, a specialist in orthopedics and traumatology involved in the research, joint pain is more accurately tied to age-related degeneration rather than to meniscus tears alone.
"The surgery is based on the assumption that pain in the inside of the knee is caused by a medial meniscus tear, which can be treated surgically," Sihvonen explained. "Such reasoning, assumption based on biological credibility, is still very common in medicine but in this case, the assumption does not withstand critical examination."
This is not the first warning sign. Earlier observational studies and clinical registries had already flagged potential harms, including higher rates of joint replacement and post-operative complications. Randomized trials over the past several years also found no improvement in symptoms or function at one, two, or five-year marks. Yet the procedure persisted.
The lag between evidence and practice illustrates a stubborn reality in medicine. Major clinical guidelines from independent organizations have recommended discontinuing the surgery for nearly a decade. Yet prestigious bodies like the American Academy of Orthopedic Surgeons and the British Association for Surgery of the Knee have continued to endorse it, signaling how difficult it is to abandon even ineffective treatments once they become entrenched.
"This effectively illustrates how difficult it is to give up inefficient therapies," Järvinen said.
The FIDELITY study was conducted across five Finnish hospitals, reflecting a collaborative effort among university hospitals in Helsinki, Kuopio, and Turku, as well as Hatanpää Hospital in Tampere and Hospital Nova in Jyväskylä. The findings were published in the New England Journal of Medicine.
Author Jessica Williams: "This is a textbook example of how even the most common surgeries deserve scrutiny, and how slowly medicine moves to correct its mistakes."
Comments