Male gender, Charnley class C, and severity of bone defects predict the risk for aseptic loosening in the cup of ABG I hip arthroplasty.
BACKGROUND
We studied which factor could predict aseptic loosening in ABG I hip prosthesis with hydroxyapatite coating. Aseptic loosening and periprosthetic osteolysis are believed to be caused, at least in part, by increased polyethylene (PE) wear rate via particle disease. Based on it, increased PE wear rate should be associated with aseptic loosening regardless of the type of implant.


METHODS
We analyzed data from 155 revisions of ABG I hip prostheses to examine the influence of patient, implant, surgery, and wear related factors on the rate of aseptic loosening at the site of the cup. This was calculated by stepwise logistic regression analysis. The stability of the implant and severity of bone defects were evaluated intraoperatively.


RESULTS
We found that men (odds ratio, OR = 5.6; p = 0.004), patients with Charnley class C (OR = 6.71; p = 0.013), those having more severe acetabular bone defects (OR = 4 for each degree of severity; p = 0.002), and longer time to revision surgery (OR = 1.51 for each additional year; p = 0.012) had a greater chance of aseptic loosening of the cup. However, aseptic loosening was not directly predicted by polyethylene wear rate in our patients.


CONCLUSIONS
Severity of bone defects predicts the risk for aseptic loosening in ABG I cup. Factors potentially associated with the quality of bone bed and biomechanics of the hip might influence on the risk of aseptic loosening in this implant.
Department of Orthopaedics, Palacky University Faculty of Medicine and Dentistry & Teaching Hospital, Olomouc, Czech Republic. jiri.gallo@volny.cz
Jiri
J
Gallo
Vitezslav
V
Havranek
Jana
J
Zapletalova
Jiri
J
Lostak
D000368:Aged; D019644:Arthroplasty, Replacement, Hip / Q000009:adverse effects*; D018450:Disease Progression; D005260:Female; D006621:Hip Joint / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery*; D006801:Humans; D008297:Male; D008875:Middle Aged; D015207:Osteoarthritis, Hip / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery*; D011183:Postoperative Complications / Q000453:epidemiology*; D011475:Prosthesis Failure / Q000639:trends*; D011859:Radiography; D012307:Risk Factors; D012720:Severity of Illness Index; D012737:Sex Factors