A Comparison of Two Metal Surface Finishes on Femoral Components in Hip Arthroplasty

University of Aarhus

Status

Completed

Conditions

Osteoarthritis

Treatments

Device: Femoral implant (Versys Fiber Metal Taper®)

Study type

Interventional

Funder types

Other

Industry

Identifiers

NCT00116038

20030192

Details and patient eligibility

About

The purpose of this study is to compare metal surface finishes (proximal-coated titanium surface versus mid-coated titanium surface) on femoral components in hip arthroplasty.

Full description

In younger patients femoral components are most often implanted without the use of cement. A direct ingrowth of bone to the implant is crucial to the attainment of good results in those cases where cement is not employed.

The construction of a femoral implant, Versys Fiber Metal Taper®, by Zimmer includes a more extensive coating than previous femoral implants. The improved surface coating has been shown to provide these implants with better properties than those demonstrated by implants currently in general use.

Theoretically, the greater porous surface of mid-coated implants should:

Encourage bone ingrowth through improved osteoconductive properties, however more extensive coating might change the loss of bone due to stress shielding later in time
Improve anchorage of the implant due to the higher friction coefficient
Result in fewer postoperative complaints measured with the Harris Hip Score and visual analog scale scores

The migration of femoral components will be evaluated by RSA, performing radiostereometric analyses at the Orthopaedic Center, Aarhus University Hospital. The follow-up RSA will be scheduled for week 1, as well as 3 months, 12 months and 2 years after surgery. Bone mineral density around the implanted femoral component will be examined by DEXA scan at week 1, as well as 1 year and 2 years after surgery.

Sex

All

Ages

50 to 70 years old

Volunteers

No Healthy Volunteers

Inclusion criteria

Patients with primary arthritis in the hip.
Patients with sufficient bone density to allow uncemented implantation of a femoral component.
Informed patient consent in writing.

Exclusion criteria

Patients with neuromuscular or vascular disease in the affected leg.
Patients found upon operation to be unsuited for uncemented acetabulum component.
Patients who regularly take non-steroid anti-inflammatory drugs (NSAID) and cannot interrupt intake for the postoperative phase of the study.
Patients with fracture sequelae.
Female patients of childbearing capacity.
Hip joint dysplasia.
Sequelae to previous hip joint disorder in childhood.