Migration of hip replacements using radiostereometric analysis v1
Research type
Research Study
Full title
A PROSPECTIVE, RANDOMISED, SINGLE CENTRE CLINICAL STUDY COMPARING STABILITY OF THE CEMENTLESS TRIFIT FEMORAL STEM VERSUS THE CEMENTLESS POLAR STEM BY RADIOSTEREOMETRIC ANALYSIS
IRAS ID
168373
Contact name
Fares S Haddad
Contact email
Sponsor organisation
University College London
ISRCTN Number
ISRCTN11320405
Duration of Study in the UK
4 years, 0 months, 0 days
Research summary
Total hip replacement is a highly successful and cost-effective means of addressing pain and disability from arthritis. Unfortunately, these implants have a limited survival with many failing after 15-20 years. The most common reason for failure is gradual loosening over time and there is a 5-20% risk of requiring a re-operation 10 years after surgery.
Research has shown that the initial stability of the implant in the bone within the first 2 years after surgery is of vital importance. The stability of an implant refers to the motion of the hip replacement in relation to the surrounding bone. It has been shown that early movement of an implant over the first 2-years after surgery is predictive of the implant going on to fail.
This study uses the method of radiostereometric analysis to compare the movement of two contrasting hip replacement designs over 2-years following surgery. Radiostereometric analysis was developed in 1974 and certain countries demand this type of research before releasing a new implant on to the market. It involves the insertion of tiny metal beads in the bone around the implants, x-rays and the measurement of movement to a very high degree of accuracy. These beads are safe and no adverse reaction to them has ever been reported.
The two implants have coatings to encourage the patient’s bone to grow on tightly and do not require cement. The results of this study will be extremely useful to determine which implant was more stable during these 2 years. We will be given very precise information as to how the implants moved during this time and in what direction. This will allow us to predict which implant we would expect to last the longest and which design is most favourable.
REC name
London - Bromley Research Ethics Committee
REC reference
15/LO/0661
Date of REC Opinion
17 Jun 2015
REC opinion
Further Information Favourable Opinion