Radiostereometric Analysis (RSA) and DEXA to Evaluate Fixation and Wear of the Restoration ADM Acetabular System

This study is ongoing, but not recruiting participants.
Information provided by (Responsible Party):
Michael Dunbar, Dalhousie University Identifier:
First received: January 7, 2011
Last updated: March 28, 2014
Last verified: March 2014

The dual mobility design concept for acetabular liners, as is used in the Restoration ADM Acetabular System, has been applied in various implants since its introduction by Gilles Bousquet in France in 1976. Dual mobility cups have shown good clinical results and have been particularly lauded for low incidence of dislocations. However, the wear performance of this design concept has not been proven to date. As wear particles are a possible contributing factor in aseptic loosening, the assessment of wear and fixation is an important step in proving this implant design.

The proposed study will combine RSA and peri-prosthetic bone mineral density as well as outcome questionnaires to provide a complete in vivo evaluation of prosthesis fixation, polyethylene wear, and objective and subjective outcomes for the Restoration ADM Acetabular System.

Condition Intervention
Device: ADM Cup

Study Type: Observational
Study Design: Observational Model: Cohort
Time Perspective: Prospective
Official Title: Prospective Clinical Study Using Radiostereometric Analysis (RSA) and DEXA to Evaluate Fixation and Wear of the Restoration ADM Acetabular System

Resource links provided by NLM:

Further study details as provided by Dalhousie University:

Primary Outcome Measures:
  • RSA migration [ Time Frame: 3 years ] [ Designated as safety issue: No ]

Secondary Outcome Measures:
  • RSA wear [ Time Frame: 3 years ] [ Designated as safety issue: No ]
  • Questionnaires [ Time Frame: 3 years ] [ Designated as safety issue: No ]

Estimated Enrollment: 30
Study Start Date: November 2011
Estimated Study Completion Date: April 2016
Estimated Primary Completion Date: April 2015 (Final data collection date for primary outcome measure)
Groups/Cohorts Assigned Interventions
Device: ADM Cup
Other Name: Styrker ADM Acetabular Cup

Detailed Description:

Question 1: a) Do the implant components of the Restoration ADM Acetabular System achieve adequate fixation to the underlying bone? Null Hypothesis: There is no significant increase in micromotion of the implant components after 1 year indicating adequate long-term fixation at the implant - bone interface. Alternative Hypothesis: There is a significant increase in micromotion of of the implant components after 1 year indicating inadequate fixation at the implant - bone interface. b) What are the migration patterns (translations and rotations) of the Restoration ADM Acetabular System components during the first three years postoperatively? c) For what proportion of implants does migration continue to increase during the three year follow-up? d) Are inducible displacements, measured during weight-bearing follow-up exams, consistent over time and do they indicate that adequate fixation has been achieved? e) Are there significant differences in migration patterns (translations and rotations) between the Restoration ADM Acetabular System components and other implants previously studied with RSA and reported in the literature? Question 2: a) How much does the femoral head wear into the polyethylene liner?b)How much backside wear occurs on the polyethylene liner? c)How does the total wear compare to that with other implants previously reported in the literature? Question 3: Does the polyethylene liner demonstrate mobile bearing properties? Question 4: a) Are there changes over time in bone mineral density of peri-prosthetic bone with the Restoration ADM Acetabular System components? b) Where do changes in bone mineral density occur? Question 5: Does total hip arthroplasty using the Restoration ADM Acetabular System result in significant improvement in health status and functional outcome?


Ages Eligible for Study:   21 Years to 80 Years
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   No
Sampling Method:   Non-Probability Sample
Study Population

Osteoarthritis of the hip


Inclusion Criteria:

  1. Symptomatic osteoarthritis of the hip indicating primary total hip arthroplasty
  2. Between the ages of 21 and 80 inclusive
  3. Patients willing and able to comply with follow-up requirements and self-evaluations
  4. Ability to give informed consent

Exclusion Criteria:

  1. Inflammatory arthritis
  2. BMI >40
  3. Post-traumatic arthritis of the hip
  4. Prior arthroplasty with the affected hip
  5. Hip dysplasia
  6. Active or prior infection
  7. Medical condition precluding major surgery
  8. Severe osteoporosis or osteopenia
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its identifier: NCT01273324

Canada, Nova Scotia
Capital District Health Authority
Halifax, Nova Scotia, Canada, b3h3a7
Sponsors and Collaborators
Dalhousie University
Principal Investigator: Michael Dunbar, FRCSC, PhD Dalhousie University
  More Information

No publications provided

Responsible Party: Michael Dunbar, MD, PhD, Dalhousie University Identifier: NCT01273324     History of Changes
Other Study ID Numbers: CDHA-RS/2012-079
Study First Received: January 7, 2011
Last Updated: March 28, 2014
Health Authority: Canada: Health Canada

Keywords provided by Dalhousie University:

Additional relevant MeSH terms:
Joint Diseases
Musculoskeletal Diseases
Rheumatic Diseases processed this record on October 19, 2014