title: Two-year radiostereometric analysis evaluation of femoral head penetration in a challenging population of young total hip arthroplasty patients.
abstract: This prospective, randomized protocol evaluated femoral head penetration after total hip arthroplasty in a young population. Forty-five patients randomly received either a cross-linked or conventional ultrahigh-molecular-weight polyethylene (UHMWPE) liner in a noncemented hemispheric cup (Trilogy, Zimmer, Warsaw, Ind) with a 28-mm femoral head. Radiostereometric analysis film pairs, Harris hip, UCLA, SF-12, and Western Ontario and McMaster Universities scores were obtained through 2 years. Median femoral head penetration was less among cross-linked compared to conventional liners as follows: 0.06 mm (0.04-0.08 mm) vs 0.08 mm (0.02-0.19 mm) at 6 months, 0.07 mm (-0.14 to 0.16 mm) vs 0.11 mm (0.01-0.27 mm) at 1 year, and 0.065 mm (-0.04 to 0.193 mm) vs 0.169 mm (0.09-0.22 mm) at 2 years. Clinical outcomes were similar between the groups. Highly cross-linked UHMWPE demonstrated 55% less femoral head penetration compared to conventional polyethylene at 2 years. Despite improvements in the manufacturing process and sterilization of conventional UHMWPE, the femoral head penetration rate is unchanged from historical standards.
authors.affiliation: Department of Orthopedic Surgery and Physical Rehabilitation, University of Massachusetts Medical School, Worcester, Massachusetts 01605-2982, USA.
authors.forename: David C
authors.initials: DC
authors.lastname: Ayers
authors.forename: Peyton L
authors.initials: PL
authors.lastname: Hays
authors.forename: Jacob M
authors.initials: JM
authors.lastname: Drew
authors.forename: Mark S
authors.initials: MS
authors.lastname: Eskander
authors.forename: Daniel
authors.initials: D
authors.lastname: Osuch
authors.forename: Charles R
authors.initials: CR
authors.lastname: Bragdon
mesh_terms: D000368:Aged; D019644:Arthroplasty, Replacement, Hip / Q000295:instrumentation* / Q000379:methods*; D005260:Female; D005270:Femur Head / Q000000981:diagnostic imaging*; D005271:Femur Head Necrosis / Q000601:surgery; D006801:Humans; D008297:Male; D008875:Middle Aged; D015207:Osteoarthritis, Hip / Q000601:surgery; D020959:Polyethylene; D011446:Prospective Studies; D011475:Prosthesis Failure; D011859:Radiography; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D020959:Polyethylene