title: Risk factors for heterotopic ossification in total hip arthroplasty.
abstract: This study prospectively evaluated 928 patients with 1318 primary total hip replacements for heterotopic ossification (HO). The mean clinical and radiological follow-up was 2.5 years (range 1.5-3.6 years). HO was noted in 44.6% of all total hips replaced. It was graded as mild (Brooker 1) in 29.2%, moderate (Brooker 2) in 10.5%, and severe (Brooker 3 and 4) in 4.2%. The following factors showed a significantly increased risk of HO: hypertrophic osteoarthritis, HO after contralateral total hip replacement, trochanteric osteotomy, lateral or anterolateral approach, previous hip surgery, subtrochanteric femoral osteotomy, and male gender (p < 0.05 in chi-square analysis of independence and multivariable analysis). Patients with rheumatoid arthritis showed less HO. A combination of any of these factors resulted in a significant increase in the risk of developing HO.
authors.affiliation: Department of Orthopaedic Surgery, University of Berne, Inselspital, Switzerland. seggli@netscape.net
authors.forename: S
authors.initials: S
authors.lastname: Eggli
authors.forename: A
authors.initials: A
authors.lastname: Woo
mesh_terms: D000368:Aged; D001172:Arthritis, Rheumatoid / Q000601:surgery; D019644:Arthroplasty, Replacement, Hip; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009999:Ossification, Heterotopic / Q000453:epidemiology*; D015207:Osteoarthritis, Hip / Q000601:surgery; D011183:Postoperative Complications / Q000453:epidemiology*; D015995:Prevalence; D011446:Prospective Studies; D012307:Risk Factors