title: A randomised study of peri-prosthetic bone density after cemented versus trabecular fixation of a polyethylene acetabular component.
abstract: The ideal acetabular component is characterised by reliable, long-term fixation with physiological loading of bone and a low rate of wear. Trabecular metal is a porous construct of tantalum which promotes bony ingrowth, has a modulus of elasticity similar to that of cancellous bone, and should be an excellent material for fixation. Between 2004 and 2006, 55 patients were randomised to receive either a cemented polyethylene or a monobloc trabecular metal acetabular component with a polyethylene articular surface. We measured the peri-prosthetic bone density around the acetabular components for up to two years using dual-energy x-ray absorptiometry. We found evidence that the cemented acetabular component loaded the acetabular bone centromedially whereas the trabecular metal monobloc loaded the lateral rim and behaved like a hemispherical rigid metal component with regard to loading of the acetabular bone. We suspect that this was due to the peripheral titanium rim used for the mechanism of insertion.
authors.affiliation: Hairmyres Hospital, Eaglesham Road, East Kilbride G75 8RG, UK. kumarranitha@yahoo.com
authors.forename: K
authors.initials: K
authors.lastname: Periasamy
authors.forename: W S
authors.initials: WS
authors.lastname: Watson
authors.forename: A
authors.initials: A
authors.lastname: Mohammed
authors.forename: H
authors.initials: H
authors.lastname: Murray
authors.forename: B
authors.initials: B
authors.lastname: Walker
authors.forename: S
authors.initials: S
authors.lastname: Patil
authors.forename: R M D
authors.initials: RM
authors.lastname: Meek
mesh_terms: D015502:Absorptiometry, Photon; D000077:Acetabulum / Q000503:physiopathology / Q000601:surgery*; D000368:Aged; D000369:Aged, 80 and over; D019644:Arthroplasty, Replacement, Hip / Q000379:methods; D015519:Bone Density; D002484:Cementation / Q000379:methods; D005260:Female; D006622:Hip Prosthesis; D006801:Humans; D008297:Male; D008875:Middle Aged; D020959:Polyethylene; D011184:Postoperative Period; D011474:Prosthesis Design; D013635:Tantalum; D016896:Treatment Outcome; D016474:Weight-Bearing
chemical_list: D013635:Tantalum; D020959:Polyethylene