A new study, which used criteria for knee replacements developed by Antonio Escobar, MD, of Hospital de Basurto, and colleagues, found that one-third of knee replacements performed in the United States may be inappropriate. According to a Reuters news report, the number of total knee replacement surgeries done each year has more than doubled between 1991 and 2010, leading some to question whether the medical procedure is overused. Daniel Riddle and his research team analyzed data from a study of about 4,800 people in the US to get a better idea of what factors were driving the increase.

The researchers analyzed data from the study, which included people with knee osteoarthritis (OA) or who were at high risk of the condition. During the study period, 205 of them had total knee replacement surgery. The criteria used to analyze the data notes that surgeries were judged to be appropriate, inappropriate, or inconclusive considering factors such as a person’s range of motion, pain, and arthritis severity. The Reuters news report indicates that based on prior studies, the researchers expected to find that about 20% of surgeries were inappropriate.

However, the research team found that about 34% of patients had total knee replacements that were deemed to be inappropriate. For the most part, the patients had symptoms that were moderate at worst and joint damage that was not widespread.

The findings of the study, published in Arthritis & Rheumatology, also showed that less than half of knee replacements, 44%, were classified as appropriate. This leaves about 22% in the inconclusive category, and this included patients with severe symptoms who had less joint damage and normal mobility or were younger than 55 years old.

Riddle notes that “the scientific content and the standard at the time (this system) was developed is clearly different from that in the US in 2014,” as indicated on the Reuters news report. He adds that doctors and patients need to do a thorough job deciding when it’s the right time for a knee replacement, if ever. Riddle says, “I would encourage patients to gather and share information with their family physician and surgeon to determine if they are good candidates for the procedure.”

The Reuters news report notes that the authors say that research should now focus on developing a system to separate inappropriate from appropriate knee replacements that is based around US patients.

[Source: Reuters]