Using EOS scans of Total Knee Arthroplasty (TKA) patients for RadioStereometric Analysis (RSA)

Eligibility

Inclusion Criteria:

  • Halifax Infirmary research participant who has undergone a TKA procedure with RSA bead implantation
  • Expressed willingness to be contacted about future research
  • Ability to bear weight on both legs

Exclusion Criteria:

  • Participants experiencing serious post-operative pain
  • Participants having undergone revision surgeries
  • Participants with uncommon post-operative complications
  • Inability to communicate in English

Contact

PI
Dr Ron El-Hawary

Description

Total Knee Arthroplasty (TKA) is a procedure conducted to replace knee joints deteriorated by osteoarthritis and rheumatoid arthritis. One to two millimeters of implant micromotion within two years post-operatively is linked to a higher likelihood of revision 5 to 10 years postoperatively. This micromotion is at a level currently below the threshold of detection of traditional x-rays. Radio Stereometric Analysis (RSA) is a highly accurate method to determine micromotion between two rigid bodies and has been used extensively to study prosthesis stability in adults. RSA application to paediatric populations has been limited, possibly due to the radiation dose in each X-ray exam. Multiple X-ray exposures early in one’s life has been linked to increase risk of cancer in the body. An alternative X-ray imager, the EOS imager recently acquired by the IWK Health Centre, can reduce radiation dose 6 to 9 times depending on anatomical location. However, the EOS imager has never been used to perform RSA measurements. We have an overarching project to develop RSA for the EOS imager. For that project we have improved the imager’s precision and performed successful RSA based on computer modeling and phantom studies. We have not yet tested the ability of the new system to use human images.

The current study aims to demonstrate RSA within the EOS imaging modality and indicate the amount of error with this technique using Total Knee Arthroplasty (TKA) human subjects. To extract maximum benefit from the human EOS radiographs, the radiographs will also be used to indicate the suitability of EOS radiographs for Hip-Knee-Ankle (HKA) angle determination.

Sample size= 15