Aims: To compare acetabular surface treatments in alumina on alumina clinical trial. Methods: Utilizing new improved alumina ceramic materials and implant design, 514 hips were implanted in a US IDE prospective randomized study. All patients received the same press-þt hydroxylapatite-coated (HA) femoral stem. Two-thirds (349 hips) received an alumina ceramic bearing surface, while one-third (165 hips) received a cobalt chrome on polyethylene bearing. The alumina group was further divided with approximately one-half receiving a porous-coated titanium shell and alumina insert (172 hips Ð System I), and one-half receiving an arc deposited titanium shell with HA coating and alumina insert (177 hips Ð System II). System III, the control group, had a porous-coated titanium shell and polyethylene insert. All acetabular shells were of identical external geometry. Results: At latest follow-up, minimum 2 years (2–4 year range), differences were noted in the pattern of development of radiolucent lines around the acetabular components. Radiolucent lines were noted most commonly in De Lee Charnley Zone 3 in porous-coated shells (25/164 hips Ð System I, 33/151 hips Ð System III respectively). Radiolucent lines in Zone 3 were absent in the arc deposited with HA shells (System II) (p=0.001). Conclusions: These results appear to demonstrate that PSL style cups with arc dep and HA coating may improve levels of primary þxation versus that of porous-coated acetabular components.

Aims: Todayñs major challenge for total hip arthroplasty is to minimize wear and osteolysis in our younger and more active patients. Alumina ceramic bearings have known superior wear resistance and lubrication and do not carry a risk of ion release. One objective of this clinical study was to evaluate the use of alumina-on-alumina ceramics with proven implants that have had successful track records with regard to þxation (on a prospective randomized basis)Methods: Utilizing new improved alumina ceramic materials and implant design 514 hips were implanted in a multicenter US IDE prospective and randomized study. The study compared alumina-on-alumina ceramic bearings to a cobalt chrome-on-polyethylene bearing. All patients received the same press-þt hydroxylapatite-coated femoral stem while two-thirds (349 hips) received alumina ceramic bearings and one-third (165 hips) received the cobalt chrome-on-polyethylene bearing. Results: With a mean follow-up of greater than 40 months (36–60 months) there is no signiþcant difference in clinical performance between the two patient cohorts. Radiographically proximal femoral osteolysis has been noted in the control patients but in no patients that received the ceramic bearing. With Continued Access, a total of 947 alumina ceramic bearings have been implanted to date. There have been no ceramic fractures or alumina bearing failures. Conclusions: This new alumina-alumina ceramic bearing provides for a safe option for the younger and more active patient population.