Partial meniscectomy – a form of arthroscopic surgery for patients with a torn meniscus, a rupture of the fibrocartilage strips in the knee – is ineffective for individuals with mechanical symptoms of degenerative knee. This is a conclusion of a new study recently published in The Annals of Internal Medicine.

A torn meniscus is one of the most common symptoms of degenerative knee – the deterioration of the knee joint with age. It occurs when one of the two menisci in the knee – the C-shaped pieces of cartilage that protect and cushion the thighbone and shinbone – become damaged. Many people with knee degeneration may experience mechanical symptoms such as joint locking or catching, which are often attributed to a section of the knee joint becoming lodged between the joint surfaces as a result of friction caused by a torn meniscus.

According to the story in Medical News Today, partial meniscectomy – the surgical removal of the damaged part of a torn meniscus – has become standard practice for patients with mechanical symptoms, despite there being insufficient evidence that it is beneficial. “Orthopedists are largely unanimous on the benefits of arthroscopic surgery on patients suffering from mechanical symptoms. However, scientific proof of the benefits is scarce, and before our study, entirely based on uncontrolled follow-up studies,” says coauthor Dr. Raine Sihvonen, a specialist in orthopedics at the Hatanpää Hospital in Tampere, Finland.

For their study, the researchers set out to gain a better understanding of the effectiveness of partial meniscectomy for such patients. The team analyzed the data of 146 patients aged 35-65 who were part of the Finnish Degenerative Meniscal Lesion Study (FIDELITY). All patients had experienced pain in the inner side of their knee for at least 3 months, which clinical examination and MRI suggested was down to a torn meniscus.
The patients were free of knee osteoarthritis – a condition commonly associated with degenerative knee – and meniscus damage had not been caused by an isolated trauma. Each patient’s torn meniscus was confirmed through diagnostic keyhole surgery. The patients were then randomized to receive either a partial meniscectomy or a sham treatment.

Based on their findings, Prof. Järvinen concludes that “the partial removal of a degenerative torn meniscus does not reduce or alleviate mechanical symptoms when compared with sham surgery.” Additionally, the researchers say their findings suggest that trauma-related meniscal tearing and degenerative meniscal tearing are two separate conditions and should be treated as such.