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

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ClinicalTrials.gov Identifier: NCT00116948
Recruitment Status : Completed
First Posted : July 1, 2005
Last Update Posted : December 5, 2014
Information provided by (Responsible Party):

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

Condition or disease Intervention/treatment Phase
Osteoarthrosis Device: ReCap, Hip resurfacing system, Biomet Phase 4

Detailed 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.

Study Design

Study Type : Interventional  (Clinical Trial)
Estimated Enrollment : 50 participants
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single (Outcomes Assessor)
Primary Purpose: Treatment
Official Title: A Comparison of Two Total Hip Replacements: Hip Resurfacing System Versus Mallory-Head/Exeter
Study Start Date : January 2005
Primary Completion Date : September 2011
Study Completion Date : January 2012

Resource links provided by the National Library of Medicine

MedlinePlus related topics: Hip Replacement
U.S. FDA Resources

Arms and Interventions

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

Outcome Measures

Primary Outcome Measures :
  1. Metal ion release evaluated in urine [ Time Frame: three years ]
  2. Gait pattern evaluated with 3D gait analysis, Vicon Polygon [ Time Frame: two years ]
  3. Bone mineral density (BMD) in surrounding bone of the prosthesis [ Time Frame: three years ]
  4. Prostheses migration evaluated by radiostereometric analysis (RSA) [ Time Frame: three years ]
  5. Proinflammatory- and bone degradation measures in blood samples [ Time Frame: three years ]

Eligibility Criteria

Information from the National Library of Medicine

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Ages Eligible for Study:   50 Years to 65 Years   (Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

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
Contacts and Locations

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT00116948

Orthopaedic Center, Aarhus University Hospital
Aarhus, Jylland, Denmark, 8000
Sponsors and Collaborators
University of Aarhus
Biomet Merck Aps,Horsens, Denmark
Gigtforeningen,Gentoftegade 118, Gentofte, Denmark
Sahva A/S, Borgervænget 5-7, København Ø, Denmark
Danske Fysioterapeuter,Nørre Voldgade 90, København, Denmark
Regionshospitalet Silkeborg
Finnish Institute of Occupational Health
Regionshospitalet Hammel Neurocenter
Principal Investigator: Kjeld Søballe, MD., Prof. Orthopaedic Center, Aarhus University Hospital, Aarhus, Denmark
More Information

Responsible Party: University of Aarhus
ClinicalTrials.gov Identifier: NCT00116948     History of Changes
Other Study ID Numbers: 20030289
First Posted: July 1, 2005    Key Record Dates
Last Update Posted: December 5, 2014
Last Verified: December 2014

Keywords provided by University of Aarhus:
Hip arthroplasty
Metal ion
Inflammatory response
Gait analysis

Additional relevant MeSH terms:
Joint Diseases
Musculoskeletal Diseases
Rheumatic Diseases