Source: DGNews  |  Posted 6 years ago

By Jill Stein

WASHINGTON, DC -- February 28, 2005 -- Investigators have documented for the first time that nonsteroidal anti-inflammatory drugs (NSAIDs) increase the likelihood that a non-cemented total hip arthroplasty (THA) will require revision due to aseptic loosening.

Per Kjaersgaard-Andersen, MD, Chief of Orthopaedics Service, Vejle Hospital, Vejle, Denmark, presented the findings here on February 25[^]th[] at the 2005 Annual Meeting of the American Academy of Orthopaedic Surgeons.

The study estimated the risk of aseptic loosening after THA using information from the Danish Hip Registry (DHR). The results also show that NSAIDs help prevent cemented THA from aseptic loosening.

The DHR is a database that tracks patients undergoing THA that includes treatment with NSAIDs in the early postoperative phase for the prevention of heterotopic ossification.

Previously, animal studies demonstrated that NSAIDs decrease bony ingrowths in non-cemented implants, weaken fracture healing, and reduce bone quality in spinal fusion, Dr. Kjaersgaard-Andersen pointed out. However, no clinical studies had shown that NSAIDs increase the risk for aseptic loosening of THA.

During 1995 to 2003, a total of 47,115 THAs were recorded in the DHR. Of these, 24,627 were cemented, 9,122 were non-cemented, and 13,366 were hybrids. Overall, 7,780 cases were treated with NSAIDS for at least 5 days in the early postoperative period.

Results show that patients who were treated with NSAIDs immediately after undergoing non-cemented THA had a significantly increased risk for revision due to aseptic loosening (RR = 2.96).

However, in patients undergoing cemented THA, NSAIDs were associated with a reduced risk for revision due to aseptic loosening (RR=0.76). The observed "protective" effect of NSAIDs in cemented THA may be a result of inhibition of the inflammatory response at the cement-bone interface caused by the NSAIDs, Dr. Kjaersgaard-Andersen suggested. This, in turn, prevents osteolysis, bone resorption, and membrane formation.

He emphasized that the results should be interpreted with caution given that they are based on data from a national registry.

[Presentation title: "Aseptic Loosening of Non-cemented Total Hip Arthroplasty after Treatment With NSAIDs." Paper 317]