Hip surgery, especially hip joint replacement, is a common operation around the world. Any trauma to the hip can cause bits of bone to form within the soft tissues around the hip. This condition is called heterotopic ossification (HO).
There are risk factors for HO, but many patients without any risk factors develop it after total hip replacement surgery. For this reason, the authors of this study think prevention of HO is important for all patients, not just those with known risk factors.
Radiation can be used, but there are many concerns about the costs and side effects of radiation therapy. Drugs, such as COX-1 and COX-2 inhibitors, may work. These are anti-inflammatory drugs used instead of aspirin. They tend to have fewer side effects on the gut. The COX-2 inhibitor is a new class of anti-inflammatory drug. It inhibits the COX-2 enzyme (in the gut), but leaves the COX-1 enzyme alone. In this study researchers in Italy compare the two drugs in patients after a total hip replacement.
Four hundred patients were divided into two groups. The first group received indomethacin (a COX-1 and COX-2 inhibitor). The second group got celecoxib (a COX-2 inhibitor). All patients started taking the drug the day after the operation. They kept taking it for 20 days.
The authors report no difference between the two groups when it comes to number of patients who developed HO. There was a difference in how many patients had side effects from the drug. About eight percent of the patients taking indomethacin had enough side effects to stop taking the drug. This compared with only two percent in the celecoxib group.
In other words, celecoxib was just as good as indomethacin in preventing HO, yet without as many unpleasant side effects. The authors advise that steps should be taken to prevent HO in any patient having major hip surgery. They conclude that celecoxib is an effective COX-2 inhibitor that can be used to prevent HO.