New Study Indicates Knee Replacement Data Lacking for Long-Term Safety and Effectiveness

Knee replacement surgery has long helped many patients with severe arthritis, but a new study published online today, March 6th 2012, in the Lancet reveals that not enough is known about patient outcomes or the effectiveness of various implants, and consensus is lacking about the precise indications for the procedure.

The authors, based in the United Kingdom, Sweden, and Australia, write that surgeons need improved decision-making as more and more possible candidates for new knees are younger than 55 years — a group that has a higher rate of revision or follow-up surgery. On another problematic note, some patients undergo the operation despite having good functional ability and only mild pain beforehand.  The article, based on a literature review going back to 1970, raises doubts about the evidence on orthopaedic joint implant safety and effectiveness.

Andrew Carr, lead author of the Lancet article, writes that the number of total knee replacements (TKRs) per 100,000 people in the United States increased more than seven fold from 1971 to 2008, for a total of more than 650,000 procedures in 2008.

“No clear consensus exists within the surgical community about exact indications, particularly severity of preoperative symptoms, obesity, and age,” Dr. Carr and coauthors write. They point to a task force organized by the Osteoarthritis Research Society International and a rheumatology organization that found that “pain, function, and radiographic severity are not associated with a surgeon’s recommendation for knee replacement.”

In addition to recommending better patient selection and better reporting of outcomes, the authors also call for new strategies to treat early-stage osteoarthritis in younger patients that will “avoid the need for major surgery altogether.”