Potential role of multislice SPECT/CT in impingement syndrome and soft-tissue pathology of the ankle and foot

Abstract

Impingement syndrome and soft-tissue pathology have been recognized as significant causes of chronic ankle pain. Conventional bone scintigraphy was traditionally used for osseous pathology, but with the advent of single photon emission computed tomography/computed tomography (SPECT/CT) the role of bone scintigraphy in these patients is being reconsidered. The aim of this study was to assess the potential role of multislice SPECT/CT in diagnosing impingement syndrome and soft-tissue pathology of the ankle and foot. A total of 209 patients (age range: 19-80 years) underwent a two-phase Tc-99m methylene diphosphonate bone scan followed by SPECT/CT between 2006 and 2009 for various ankle and foot pathologies. These scans were reviewed for impingement syndrome and soft-tissue pathology. The diagnosis made on SPECT/CT was compared with the clinical diagnosis, and two-phase bone scan findings and additional findings obtained from SPECT/CT were noted. Out of the 209 patients, 43 (21%) were diagnosed with impingement syndrome or soft-tissue pathology. Clinical diagnosis versus bone SPECT/CT: in 24/43 (56%) patients, SPECT/CT provided information not suspected on clinical diagnosis. In 19/43 (44%) patients, SPECT/CT confirmed the clinical diagnosis. Two-phase bone scan versus SPECT/CT: in 31/43 (72%) patients, SPECT/CT provided additional information, which was not diagnosed on the conventional two-phase bone scan. The findings of the two-phase bone scan and SPECT/CT were concordant in 12/43 (28%) patients. Tc-99m methylene diphosphonate bone SPECT/CT is useful in localizing and characterizing impingement syndrome and soft-tissue pathology in patients with ankle/foot pain. SPECT/CT may complement MRI and ultrasonography in the investigation of impingement syndrome and soft-tissue pathology.