A Comparison of Two Total Hip Replacements: Hip Resurfacing System Versus Mallory-Head/Exeter

Osteoarthrosis Clinical Trial

Official title:

A Comparison of Two Total Hip Replacements: Hip Resurfacing System Versus Mallory-Head/Exeter

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT00116948
• Other study ID #: 20030289
• Status: Completed
• Phase: Phase 4
• First received: June 30, 2005
• Last updated: December 3, 2014
• Start date: January 2005
• Est. completion date: January 2012

Study information

• Verified date: December 2014
• Source: University of Aarhus
• Contact: n/a
• Is FDA regulated: No
• Health authority: Denmark: The Regional Committee on Biomedical Research Ethics
• Study type: Interventional

Clinical Trial Summary

The purpose of this study is to compare two total hip replacement systems: Hip Resurfacing System (ReCap) versus Mallory-Head/Exeter.

Description:

In Denmark approximately 7000 primary hip replacements are implanted yearly, and the incidence is rising with the increasingly aging population. For older patients, the incidence of later revisions of hip implantation is low. Unfortunately, this is not true for younger patients. Approximately 20% of patients under 55 years of age at the time of surgery must have the hip implant renewed within 10 years.

This is primarily because of the wear generated by polyethylene debris. The polyethylene is associated with osteolysis in the proximity of the prosthesis leading to failure of the prosthesis.

This unsatisfactory result has led to the development of an alternative hip prosthesis especially to benefit younger and physically active people. The new prosthesis should produce less inflammatory debris and less osteolysis induced failure.

To avoid the polyethylene particles, a new type of prosthesis has been made articulating metal on metal. The Hip Resurfacing System consists of an alloy of chrome - cobalt - molybdenum. Another point of interest for this prosthesis is also the size of the articulating surfaces which are bigger than usual. This will theoretically participate in the generation of metal ions.

Study objectives:

• This randomised prospective study will investigate the emission of Co-, Cr- and Mb-ions from Hip Resurfacing System and Mallory-Head/Exeter implants, respectively. The emission is measured as the ion concentration in the urine and is correlated to the inflammatory response in fasting plasma before and after the operation.

• To assess the walking pattern postoperatively using a 3D gait analysis, Vicon Polygon.

• To assess the postoperative recovery using the Harris hip score and visual analogue scale.

• The migration of acetabular 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, 24 months, and 5 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.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 50
• Est. completion date: January 2012
• Est. primary completion date: September 2011
• Accepts healthy volunteers: No
• Gender: Both
• Age group: 50 Years to 65 Years

Eligibility

Inclusion Criteria:

• Patient with primary hip osteoarthrosis (OA).

• Informed patient consent in writing.

• Sufficient bone density to allow uncemented implantation of an acetabular component.

Exclusion Criteria:

• Presence of other metal implants.

• Working exposure of chrome, cobalt or molybdenum.

• Ingestion of multivitamin or medication containing chrome, cobalt or molybdenum.

• Kidney disease

• Hip joint dysplasia

• Patients with neuromuscular or vascular disease in the affected leg.

• 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.

• Sequelae to previous hip joint disorder in childhood

Study Design

Allocation: Randomized, Endpoint Classification: Safety/Efficacy Study, Intervention Model: Parallel Assignment, Masking: Single Blind (Outcomes Assessor), Primary Purpose: Treatment

Related Conditions & MeSH terms

• Joint Diseases
• Osteoarthritis
• Osteoarthrosis

Intervention

Device:
• ReCap, Hip resurfacing system, Biomet
ReCap total hip arthroplasty inserted according to manufactures manual.

Locations

Country	Name	City	State
Denmark	Orthopaedic Center, Aarhus University Hospital	Aarhus	Jylland

Sponsors (8)

Lead Sponsor	Collaborator
University of Aarhus	Biomet Merck Aps,Horsens, Denmark, Danske Fysioterapeuter,Nørre Voldgade 90, København, Denmark, Finnish Institute of Occupational Health, Gigtforeningen,Gentoftegade 118, Gentofte, Denmark, Regionshospitalet Hammel Neurocenter, Regionshospitalet Silkeborg, Sahva A/S, Borgervænget 5-7, København Ø, Denmark

Country where clinical trial is conducted

Denmark, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Metal ion release evaluated in urine		three years	No
Primary	Gait pattern evaluated with 3D gait analysis, Vicon Polygon		two years	No
Primary	Bone mineral density (BMD) in surrounding bone of the prosthesis		three years	No
Primary	Prostheses migration evaluated by radiostereometric analysis (RSA)		three years	No
Primary	Proinflammatory- and bone degradation measures in blood samples		three years	No