Radiostereometric Analysis: The Hip

HSS Journal

Mathias P. Bostrom, MD
Thomas P. Sculco, MD
Bryan J. Nestor, MD
Edwin P. Su, MD
Edwin P. Su, MD
Associate Attending Orthopedic Surgeon, Hospital for Special Surgery
Friedrich Boettner, MD
Friedrich Boettner, MD

Associate Attending Orthopaedic Surgeon, Hospital for Special Surgery
Associate Professor of Orthopaedic Surgery, Weill Cornell Medical College

Bassem Azzis
Research Coordinator, Hospital for Special Surgery

Radiostereometric analysis is an accurate method of determining the migration and wear of orthopaedic implants such as total hip arthroplasties. While the overall concept of RSA is relatively straightforward: determining the precise location of two distinct objects relative to each other in three dimension such as the relative position of the femoral component and the proximal femur, the actual practical application is somewhat more complex. In radiostereometric analysis, the position in space of the original object is reconstructed from a two-dimensional x-ray film (Figure 1). In order to reconstruct the position of segments within the human body, each segment is marked with at least three tantalum beads. Movement between segments is then calculated by localizing each segment in a coordinate system.

This article appears in HSS Journal: Volume 1, Number 1.
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About the HSS Journal
HSS Journal, an academic peer-reviewed journal, is published twice a year, February and September, and features articles by internal faculty and HSS alumni that present current research and clinical work in the field of musculoskeletal medicine performed at HSS, including research articles, surgical procedures, and case reports.


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