Effectiveness of 18F-fluoro-deoxyglucose Positron Emission Tomography/Computed Tomography and Magnetic Resonance Imaging to Detect Iliopsoas Tendonitis after Total Hip Arthroplasty: A Case Report

Disorders involving artificial joints are difficult to evaluate due to metal artifacts hindering plain computed tomography (CT) or magnetic resonance imaging (MRI). In the current case study 18F-fluoro-deoxyglucose positron emission tomography (18F-FDG-PET)/CT and MRI were used to confirm iliopsoas tendonitis within the metal artifact area following total hip arthroplasty (THA). The patient was a 61-year-old woman who developed hip pain on flexion of the ipsilateral hip after THA. Imaging studies were performed to evaluate for iliopsoas tendonitis due to impingement with the cup. Assessment of the iliopsoas muscle near the artificial joint was difficult due to the metal artifact on plain CT and MRI. Imaging using 18F-FDG-PET/CT and 18F-FDG-PET/MRI showed uptake along the iliopsoas muscle. Therefore, revision was performed to resolve iliopsoas tendon impingement, and the preoperative pain resolved. The result of the current case study suggest 18F-FDG-PET/CT or 18F-FDG-PET/MRI will be useful to detect iliopsoas tendonitis within metal artifact areas after THA.