RT Journal Article SR Electronic T1 Prevalence of heterotopic ossification in cemented versus noncemented total hip joint replacement in patients with osteoarthrosis: a randomized clinical trial JF Canadian Journal of Surgery JO CAN J SURG FD Canadian Medical Association SP 368 OP 374 VO 40 IS 5 A1 K. Naresh K. Nayak A1 Brian Mulliken A1 Cecil H. Rorabeck A1 Robert B. Bourne A1 Michael R. Woolfrey YR 1997 UL http://canjsurg.ca/content/40/5/368.abstract AB Objective: To determine the prevalence of heterotopic bone formation in cemented versus noncemented total hip joint replacement.Design: A prospective randomized controlled trial. Follow-up ranged from 2 to 6 years (mean 4 years).Setting: A university hospital.Patients: Two hundred and twenty-six patients who had primary or secondary osteoarthrosis of the hip were stratified according to type of fixation, surgeon and age. Patients were randomized within strata: 112 received noncemented total hip prostheses and 114 received cemented prostheses. The 2 groups were similar with respect to age and sex.Intervention: Primary total hip arthroplasty. A cemented (methylmethacrylate) or noncemented prosthesis was inserted by a lateral surgical approach.Main outcome measure: The Brooker classification was used to grade heterotopic bone formation from postoperative radiographs.Results: Overall, 148 (66%) hips had no heterotopic ossification, 56 (25%) were Brooker class I, 14 (6%) were class II, 8 (3%) were class III and none were class IV. In the noncemented group of patients, 76 (68%) hips had no heterotopic ossification, 25 (22%) were Brooker class I, 7 (6%) were class II, 4 (4%) were class III and none were class IV. In the cemented group of patients, 72 (63%) hips had no heterotopic ossification, 31 (27%) hips were Brooker class I, 7 (6%) were class II, 4 (4%) were class III and none were class IV.Conclusion: There was no significant difference in the prevalence of heterotopic ossification between cemented and noncemented total hip replacements in patients with osteoarthrosis.