The Rift between Knee Osteoarthritis and a Torn Meniscus

Osteoarthritis (OA) of the knee can cause lots of pain and disability. Most patients with OA of the knee get magnetic resonance imaging (MRI) scans at some point in their treatment. Often, the MRI shows tears in the meniscus. The meniscus is a crescent pad of cartilage in the knee joint.

Doctors commonly suggest repairing the meniscal tear. The goal is to decrease pain and increase knee function. But does repairing meniscal tears found by MRIs really help patients with knee OA? It is not even known how common meniscal tears are in the general population, or how tears relate to the pain of knee OA.

These researchers wanted answers. They compared 154 patients over age 45 with painful knee OA to 49 people of the same age with healthy knees. All patients had X-rays, MRI scans, and pain and function measurements. The results of the two groups were then compared. The researchers found that 91 percent of the OA group had meniscal tears, compared to 76 percent of the group with healthy knees. More men than women had tears. And the people with the most severe OA all had meniscal tears.

However, there was no relationship between meniscal tears and higher levels of pain. There was also no relationship between tears and lower levels of function. The authors conclude that surgery to repair the meniscus is probably not warranted based on an MRI scan alone. There may be some patients with knee OA who need to have meniscal tears repaired. But an MRI alone shouldn't be used to determine the need for meniscal repair in patients with OA. Other measures, such as the how well a patient's knee functions, also need to be considered.

The authors note one shortcoming in their data: the OA group was significantly heavier than the healthy group. They suggest that meniscal tears are possibly related to body weight. If this is true, it could mean there is even less relationship between meniscal tears and the pain of OA.



References: Timothy Bhattacharyya, MD, et al. The Clinical Importance of Meniscal Tears Demonstrated by Magnetic Resonance Imaging in Osteoarthritis of the Knee. In The Journal of Bone and Joint Surgery. January 2003. Vol. 85-A. No. 1. Pp. 4-9.