Quantitating the effect of prosthesis design on femoral remodeling using high-resolution region-free densitometric analysis (DXA-RFA).
Dual energy X-ray absorptiometry (DXA) is the reference standard method used to study bone mineral density (BMD) after total hip arthroplasty (THA). However, the subtle, spatially complex changes in bone mass due to strain-adaptive bone remodeling relevant to different prosthesis designs are not readily resolved using conventional DXA analysis. DXA region free analysis (DXA RFA) is a novel computational image analysis technique that provides a high-resolution quantitation of periprosthetic BMD. Here, we applied the technique to quantitate the magnitude and areal size of periprosthetic BMD changes using scans acquired during two previous randomized clinical trials (2004 to 2009); one comparing three cemented prosthesis design geometries, and the other comparing a hip resurfacing versus a conventional cementless prosthesis. DXA RFA resolved subtle differences in magnitude and area of bone remodeling between prosthesis designs not previously identified in conventional DXA analyses. A mean bone loss of 10.3%, 12.1%, and 11.1% occurred for the three cemented prostheses within a bone area fraction of 14.8%, 14.4%, and 6.2%, mostly within the lesser trochanter (p < 0.001). For the cementless prosthesis, a diffuse pattern of bone loss (-14.3%) was observed at the shaft of femur in a small area fraction of 0.6% versus no significant bone loss for the hip resurfacing prosthesis (p < 0.001). BMD increases were observed consistently at the greater trochanter for all prostheses except the hip-resurfacing prosthesis, where BMD increase was widespread across the metaphysis (p < 0.001). DXA RFA provides high-resolution insights into the effect of prosthesis design on the local strain environment in bone. © 2017 The Authors Journal of Orthopaedic Research published by Wiley Periodicals, Inc. on behalf of Orthopaedic Research Society. J Orthop Res 35:2203-2210, 2017.
University of Sheffield, Academic Unit of Bone Metabolism, Northern General Hospital, Sheffield, United Kingdom.|Department of Electronic and Electrical Engineering, Centre for Computational Imaging & Simulation Technologies in Biomedicine (CISTIB), University of Sheffield, Sheffield, United Kingdom.
Mohsen
M
Farzi
University of Sheffield, Academic Unit of Bone Metabolism, Northern General Hospital, Sheffield, United Kingdom.
Richard M
RM
Morris
Department of Orthopaedic Surgery and Traumatology, Odense University Hospital, University of Southern Denmark, Institute of Clinical Research, Odense, Denmark.
Jeannette
J
Penny
University of Sheffield, Academic Unit of Bone Metabolism, Northern General Hospital, Sheffield, United Kingdom.
Lang
L
Yang
Department of Electronic and Electrical Engineering, Centre for Computational Imaging & Simulation Technologies in Biomedicine (CISTIB), University of Sheffield, Sheffield, United Kingdom.
Jose M
JM
Pozo
Department of Orthopaedic Surgery and Traumatology, Odense University Hospital, University of Southern Denmark, Institute of Clinical Research, Odense, Denmark.
Søren
S
Overgaard
Department of Electronic and Electrical Engineering, Centre for Computational Imaging & Simulation Technologies in Biomedicine (CISTIB), University of Sheffield, Sheffield, United Kingdom.
Alejandro F
AF
Frangi
University of Sheffield, Academic Unit of Bone Metabolism, Northern General Hospital, Sheffield, United Kingdom.
Jeremy Mark
JM
Wilkinson
D000328:Adult; D000368:Aged; D019644:Arthroplasty, Replacement, Hip / Q000295:instrumentation; D015519:Bone Density; D016723:Bone Remodeling; D003720:Densitometry / Q000379:methods*; D005260:Female; D005269:Femur / Q000502:physiology*; D006622:Hip Prosthesis; D006801:Humans; D008297:Male; D008875:Middle Aged; D011474:Prosthesis Design
bone mineral density; dual energy X-ray absorptiometry (DXA); false discovery rate (FDR); hip arthroplasty; strain-adaptive bone remodeling