Cyrus Brodén1,2, Joshua W Giles3,4, Ravi Popat5, Shirley Fetherston6, Henrik Olivecrona7, Olof Sandberg8, Gerald Q Maguire9, Marilyn E Noz10, Olof Sköldenberg2, Roger Emery1. 1. Department of Surgery and Cancer, Imperial College London, St Mary's Hospital, London, UK. 2. Karolinska Institutet, Department of Clinical Sciences, Danderyd Hospital, Division of Orthopaedics, Stockholm, Sweden. 3. Department of Mechanical Engineering, University of Victoria, Victoria, BC, Canada. 4. Mechatronics in Medicine Laboratory, Mechanical Engineering, Imperial College London, London, UK. 5. Department of Bioengineering, Imperial College London, London, UK. 6. Department of Radiology, St Mary's Hospital, Imperial College Healthcare NHS Trust, London, UK. 7. Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden. 8. Sectra, Linköping, Sweden. 9. School of Electrical Engineering and Computer Science, KTH Royal Institute of Technology, Stockholm, Sweden. 10. Department of Radiology, New York University School of Medicine, New York, NY, USA.
Abstract
BACKGROUND: Radiostereometric analysis (RSA) is the gold standard to measure early implant migration which is a predictive factor for implant survival. PURPOSE: To validate an alternative computed tomography (CT) technique to measure implant migration in shoulder arthroplasty. MATERIAL AND METHODS: A cadaver proximal humerus and a scapula, which had tantalum beads incorporated within them, were prepared to accept a short-stemmed humeral component and a two-pegged glenoid component of a commercial total shoulder arthroplasty (TSA) system. A five degree of freedom micrometer and goniometer equipped rig was used to translate and rotate the implant components relative to the respective bone to predetermined positions. Double CT examinations were performed for each position and CT motion analysis software (CTMA) was used to assess these movements. The accuracy and precision of the software was estimated using the rig's micrometers and goniometers as the gold standard. The technique's effective dose was also assessed. RESULTS: The accuracy was in the range of 0.07-0.23 mm in translation and 0.22-0.71° in rotation. The precision was in the range of 0.08-0.15 mm in translation and 0.23-0.54° in rotation. The mean effective dose for the CT scans was calculated to be 0.27 mSv. CONCLUSION: In this experimental setting, accuracy, precision, and effective dose of the CTMA technique were found to be comparable to that of RSA. Therefore, we believe clinical studies are warranted to determine if CTMA is a suitable alternative to traditional RSA for migration measurements in TSA.
BACKGROUND: Radiostereometric analysis (RSA) is the gold standard to measure early implant migration which is a predictive factor for implant survival. PURPOSE: To validate an alternative computed tomography (CT) technique to measure implant migration in shoulder arthroplasty. MATERIAL AND METHODS: A cadaver proximal humerus and a scapula, which had tantalum beads incorporated within them, were prepared to accept a short-stemmed humeral component and a two-pegged glenoid component of a commercial total shoulder arthroplasty (TSA) system. A five degree of freedom micrometer and goniometer equipped rig was used to translate and rotate the implant components relative to the respective bone to predetermined positions. Double CT examinations were performed for each position and CT motion analysis software (CTMA) was used to assess these movements. The accuracy and precision of the software was estimated using the rig's micrometers and goniometers as the gold standard. The technique's effective dose was also assessed. RESULTS: The accuracy was in the range of 0.07-0.23 mm in translation and 0.22-0.71° in rotation. The precision was in the range of 0.08-0.15 mm in translation and 0.23-0.54° in rotation. The mean effective dose for the CT scans was calculated to be 0.27 mSv. CONCLUSION: In this experimental setting, accuracy, precision, and effective dose of the CTMA technique were found to be comparable to that of RSA. Therefore, we believe clinical studies are warranted to determine if CTMA is a suitable alternative to traditional RSA for migration measurements in TSA.
Authors: Bart Ten Brinke; Nina M C Mathijssen; Ian F Blom; Lennard A Koster; Gerald A Kraan Journal: BMC Musculoskelet Disord Date: 2021-02-05 Impact factor: 2.362
Authors: Cyrus Brodén; Peter Reilly; Monica Khanna; Ravi Popat; Henrik Olivecrona; Dylan Griffiths; Olof Sköldenberg; Roger Emery Journal: Acta Orthop Date: 2022-02-01 Impact factor: 3.717