Most Damage, Most Gain in Knee Replacement

If you have knee osteoarthritis, you can take steps to prevent permanent damage. For those with the damage done, joint replacement surgery may relieve pain and boost knee function.

Osteoarthritis patients with the most joint damage before surgery may be the most likely to benefit from total knee replacement.

In a recent study, patients with the most damage before surgery were least likely to have major pain 1 year after surgery.

Ask your doctor if joint replacement is right for you.

For their study, Michelle Dowsey, PhD, of the University of Melbourne, and colleagues wanted to see how patients with different levels of joint damage responded to total knee replacement surgery.

On average, joint replacement surgery relieved pain and improved function. However, about 30 percent of patients did not get enough pain relief. About 50 percent of patients did not regain enough function.

The researchers looked at X-ray images to measure patients' joint damage. Patients were placed in groups according to their level of damage.

Patients with the least joint damage were up to 5.39 times more likely than those with the most damage to continue feeling moderate-to-severe pain 1 year after surgery.

Compared to patients with the most damage, those with less damage were up to 2.81 times more likely to have poor function 1 year after surgery.

For the most part, higher levels of damage before surgery were associated with greater pain relief and improved function.

For their study, the researchers grouped patients according to the Kellgren-Lawrence Grading Scale - a system for rating joint damage in osteoarthritis, where Grade 1 marks the least damage and Grade 4 marks the most.

A total of 478 osteoarthritis patients were included in the study. Before total knee replacement surgery, patients were grouped by their Kellgren-Lawrence grades.

The study was published August 6 in Osteoarthritis and Cartilage, a journal of Osteoarthritis Research Society International.