Study Finds Common Knee Surgery Offers No Lasting Benefit, May Harm Joints

A surgery long sold as a fix for torn cartilage offered no durable advantage in a 10-year Finnish trial, and the long follow-up raised fresh concern that it may speed joint damage instead.

The study tracked nearly 150 patients in the FIDELITY trial, ages 35 to 65, who had degenerative medial meniscus tears but no knee osteoarthritis at the start. Half underwent arthroscopic partial meniscectomy, while the other half received a sham operation. That design matters: it separated the true effect of surgery from placebo response and the recovery that can follow any procedure. After a decade, the surgical group showed no meaningful improvement in pain or function compared with the sham group.

The longer view was more troubling. About 81% of patients who had partial meniscectomy showed significant progression of knee arthritis, compared with 70% in the sham-surgery group. Some of the patients who had the procedure later needed knee replacement surgery. The University of Helsinki said the 10-year follow-up found not only no symptom or function benefit, but more symptoms, more reduced function, increased osteoarthritis progression and a higher probability of later knee surgery.

The findings sharpen a problem that has lingered for years: partial meniscectomy remains common even after repeated randomized trials failed to show a payoff. The original FIDELITY report in the New England Journal of Medicine in 2013 found no significant benefit over sham surgery at 12 months, and a later randomized follow-up also found no benefit at two years. In 2017, the BMJ issued a strong recommendation against arthroscopic knee surgery for degenerative knee disease, and sports medicine Choosing Wisely guidance has advised against knee arthroscopy as an initial treatment for degenerative meniscal tears without mechanical symptoms.

The persistence of the operation reflects both medical habit and the logic that once made it seem intuitive: if inside-knee pain comes from a torn meniscus, trimming the tear should help. The Helsinki investigators argued that idea does not survive critical testing, and that much of the pain in these cases is tied to age-related degeneration rather than a simple mechanical defect. Observational registry studies had already raised concern about later arthroplasty risk and possible complications after partial meniscectomy, even if those data could not prove causation.

That makes the practical question for patients immediate. Before agreeing to knee arthroscopy for a degenerative tear, ask whether the pain is really mechanical, whether there are true locking symptoms, whether physical therapy and other conservative care have been tried, and what the evidence says about long-term benefit. The stakes are large: one sports medicine source puts arthroscopic partial meniscectomy at about 700,000 procedures a year in the United States. When a common operation fails to outperform sham surgery, the costs are not just clinical. They are also financial, shaping insurer spending, operating-room time and the next decade of orthopedic practice.