Increased urinary crosslink levels in aseptic loosening of total hip arthroplasty.

Abstract

The diagnosis of aseptic loosening in total hip arthroplasty is predominantly based on clinical and radiographic evaluation. Loosening is usually associated with increased bone resorption at the interface. In this study we wanted to evaluate the diagnostic value of bone markers in aseptic loosening. We compared 50 patients with proven component loosening during surgery with 50 age-, sex-, and implant-matched patients without clinical or radiological signs of loosening. We measured serum markers of bone formation (bone-specific alkaline phosphatase, osteocalcin [OC], procollagen type I propeptides) and bone resorption (collagen n-telopeptide [NTX], deoxypyridinoline [DPYD], pyridinoline [PYD]). We found significantly increased levels of NTX, DPYD, PYD, and OC in the loosening group. The other markers showed no significant difference between both groups. We conclude that determination of urinary crosslinks may offer a new and valuable diagnostic method in the detection of aseptic loosening in total hip arthroplasty.