2015 ISAKOS Biennial Congress ePoster #1433
Efficacy of Bone Scintigraphy to Evaluate Painful Knee After Knee Arthroplasty
Yozo Katsuragawa, MD, PhD, Shinjuku-Ku, Tokyo JAPAN
Takayuki Yamamoto, MD, Kawasaki-Shi, Kanagawa JAPAN
National Center for Global Health and Medicine, Shinjuku-ku, TOKYO, JAPAN
FDA Status Not Applicable
Summary: To evaluate painful knee after arthroplasty objectively, we used bone scintigraphy and compared the maximum scintillation count of the knees.
Knee arthroplasty is a reproducible procedure with excellent long-term results. However, a few patients complain pain following surgery, causing complicated diagnostic problem.
The purpose of this study was to evaluate the efficacy of bone scintigraphy following knee arthroplasty to determine the necessity of revision surgery.
Fifty patients suffering continuous pain after knee arthroplasty underwent bone scintigraphy. The images were divided into 7 regions and the maximum scintillation count of each region were compared between affected side and control side. We set up the cut-off ratio to 2 and presumed that more than that ratio should be abnormal uptake.
Twenty patients showed significant uptake ratio at least in one region. Among them 6 patients revealed infection resulted in two-stage revision. Eleven patients were diagnosed as aseptic loosening, 4 of them were revised, 7 were under follow-up. Besides, each 1 case of progression of lateral arthrosis after UKA, inflammation of unknown origin, CRPS were under conservative treatment.
The scintigram of thirty patients showed no significant uptake ratio. One patient was operated on for changing polyethylene insert, another 29 patients were considered to have no objective problem.
The main cause of failure after knee arthroplasty are infection and aseptic loosening. Bone scintigraphy can detect the change of bone affecting these diseases earlier. Our method to evaluate the uptake numerically is simple and thought to be useful to determine the presence of objective problem after knee arthroplasty.