What works best, a cemented or cementless primary total hip arthroplasty?: minimum 17-year followup of a randomized controlled trial.
BACKGROUND
Total hip arthroplasty (THA) has been associated with high survival rates, but debate remains concerning the best fixation mode of THA.


OBJECTIVE
We conducted a randomized controlled trial (RCT) with 250 patients with a mean age of 64 years between October 1987 and January 1992 to compare the results of cementless and cemented fixation.


METHODS
Patients were evaluated for revision of either of the components. One hundred twenty-seven patients had died (51%) and 12 (4.8%) were lost to followup. The minimum 17-year followup data (mean, 20 years; range, 17-21 years) for 52 patients of the cementless group and 41 patients of the cemented group were available for evaluation.


RESULTS
Kaplan-Meier survivorship analysis at 20 years revealed lower survival rates of cemented compared with cementless THA. The cementless tapered stem was associated with a survivorship of 99%. Age younger than 65 years and male gender were predictors of revision surgery.


CONCLUSIONS
The efficacy of future RCTs can be enhanced by randomizing patients in specific patient cohorts stratified to age and gender in multicenter RCTs. Including only younger patients might improve the efficacy of a future RCT with smaller sample sizes being required. A minimum 10-year followup should be anticipated, but this can be expected to be longer if the difference in level of quality between the compared implants is smaller.


METHODS
Level I, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.
Corten
Kristoff
K
London Health Sciences Centre, University Campus, 339 Windermere Road, London, ON N6A 5A5, Canada.
Bourne
Robert B
RB
Charron
Kory D
KD
Au
Keegan
K
Rorabeck
Cecil H
CH
D000328:Adult; D000367:Age Factors; D000368:Aged; D019644:Arthroplasty, Replacement, Hip / Q000009:adverse effects / Q000295:instrumentation* / Q000379:methods*; D001843:Bone Cements / Q000627:therapeutic use*; D005260:Female; D005500:Follow-Up Studies; D006621:Hip Joint / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery*; D006622:Hip Prosthesis; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D009864:Ontario; D015207:Osteoarthritis, Hip / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery*; D016016:Proportional Hazards Models; D011474:Prosthesis Design; D011475:Prosthesis Failure; D011859:Radiography; D012086:Reoperation; D018570:Risk Assessment; D012307:Risk Factors; D012737:Sex Factors; D013997:Time Factors; D016896:Treatment Outcome
D001843:Bone Cements