The value of desoxypyridinoline in the diagnostics of loosened arthroplasty

According to several reports in the last few years, desoxypyridinoline (Dpd) in urine increases significantly in cases of loosened arthroplasty. Therefore, this marker was suggested as useful in the diagnostics of implant loosening. In this study, the level of Dpd was determined in 69 patients with arthroplasty of the hip or the knee joint. Thirty-four of these patients received revision surgery following implant loosening. In 35 of these 69 patients, there were no clinical or radiological signs of loosening (control group). The mean age of the patients with loosened implants (22 women, 13 men) was 67.9 years and of the control group (22 women, 12 men) 66.9 years. In the group with arthroplastic loosening, as well as in the control group, 14 patients had increased levels of Dpd. There were 20 patients in the group with loosened arthroplasty and 19 patients in the control group that had normal levels of Dpd. The female patients had a mean Dpd level of 8.6 nmol/mmol creatinine (4.3–24 nmol/mmol creatinine) in the urine in cases of loosening and 10.1 nmol/ mmol creatinine (2–33 nmol/mmol creatinine) in the control group. The male patients had a mean Dpd level of 7.8 nmol/mmol creatinine (3.2–19.2 nmol/mmol creatinine) in the urine in cases of loosening and 5.8 nmol/mmol creatinine (0.3–11.7 nmol/mmol creatinine) in the control group. In conclusion there was no significant increase in Dpd in patients with implant loosening compared with the control group. Furthermore, older patients often suffer from diseases causing increased bone resorption that may falsify the test results. We cannot confirm that Dpd is helpful in the diagnostics and screening of implant loosening.