ABSTRACT
BACKGROUND AND AIMS: The wear of metal-on-metal hip implants may increase chromium or cobalt ion blood level. This phenomenon may depend among other things on the particularity of spinopelvic anatomy. The effect of pelvic incidence angle on the wear of metal-on-metal hip implants is not known. The objective of the study was to investigate whether such effect does exist. MATERIAL AND METHODS: The pelvic incidence and inclination of acetabular component angles of 89 patients after unilateral metal-on-metal hip replacement were compared with blood level of chromium and cobalt ions using Pearson correlation coefficient. RESULTS: No significant correlations between pelvic incidence angle and the metal ion blood levels were observed. The correlation coefficients varied from -0.02 to 0.2 and all p values were >0.05. CONCLUSION: No evidence was found on the effect of pelvic incidence angle on metal wear after metal-on-metal hip replacement when measured by the blood levels of chromium and cobalt ions. It is reasonable to assume that other factors than pelvic tilt may affect the rate of implant wear.
Subject(s)
Arthroplasty, Replacement, Hip/adverse effects , Chromium/blood , Cobalt/blood , Hip Prosthesis , Metal-on-Metal Joint Prostheses/adverse effects , Prosthesis Failure , Aged , Aged, 80 and over , Arthroplasty, Replacement, Hip/methods , Cohort Studies , Female , Follow-Up Studies , Humans , Ions/blood , Joint Instability/diagnostic imaging , Joint Instability/etiology , Male , Materials Testing , Middle Aged , Prospective Studies , Regression Analysis , Risk AssessmentABSTRACT
The clinical and radiological outcomes of bioactive glass (BAG)-S53P4 and autograft bone (AB) used as bone-graft substitutes in depressed tibial plateau fractures were evaluated in a prospective randomized 11-year follow-up study. All patients (n = 29) had sustained tibial plateau fractures with a joint-line depression of >3 mm. Fifteen patients (5 patients the BAG group, 10 patients in the AB group) participated in this long-term follow-up. X-rays were taken preoperatively, postoperatively, and at the long-term follow-up, and computed tomography (CT) scans were made at the long-term follow-up for evaluation of the bone substitute, osteoarthritis, the tibial-femoral angle, and deviation of mechanical axes. No material-dependent adverse effects were seen in any patient. The means of the articular surface depression on X-rays at the long-term follow-up were 1.4 mm (range: 0-2 mm) in the BAG group and 1.4 mm (range: 0-4 mm) in the AB group, and on CT scans the means were 2.2 mm (range: 2-3 mm), and 2.1 mm (range: 0-3), respectively. No significant difference in the tibial-femoral angle or deviation of mechanical axes was observed between the two groups. BAG-S53P4 can be used as a bone substitute in depressed lateral tibial plateau fractures with good functional and radiological long-term results.
