RESUMO
PURPOSE: The objective of this study was to evaluate the role of magnetic resonance imaging (MRI) and ultrasonography (US) in the diagnosis of traumatic muscle injuries. MATERIALS AND METHODS: From June 2003 to June 2004, 81 football players with a history of traumatic muscle injuries to the lower limbs were examined. US was performed shortly after the trauma (from 6 to 72 h afterwards) and MRI within a maximum of 5 days. RESULTS: MRI revealed 26 minor and 55 major traumas. MRI and US showed complete concordance in 71 patients (site, type and extent of injury). US produced ten false negative results, including six minor lesions and four major lesions. US had a sensitivity of 87.65% in the correct identification of muscle injuries; its sensitivity was 92.72% for major lesions and 76.92% for minor lesions, 57% for delayed-onset muscle soreness (DOMS), 80% for lengthenings, 83% for contractures, 84% for strains, 87.5% for mild contusions and 100% for severe contusions. CONCLUSIONS: US is the first-line technique for examination of muscle injuries. MRI is able to reveal lesions that may be missed at US and provide a more accurate assessment of site and extent of injury.