We compared ultrasound (US) with magnetic resonance (MR) findings of muscle tendon and ligaments (mt&l) of 17 men and 13 women, 16-66 years old, who suffered from acute ankle injury without bone fracture visible on conventional radiographs. Joint effusion (JE), and injury of the Tibials anterior muscle tendon (TAmt), Calcaneofibular ligament (CFl), Long flexor of the great toe muscle tendon (LFGTmt), Short peroneus muscle tendon (SPmt), Long peroneus muscle tendon (LPmt), and Anterior talofibular ligament (ATFl) were assessed by the US, at seven days, and MR, at seventeenth day. Grading of ligament and muscle tendon injury as stretching (Grade 1), partially ruptured (Grade 2), and complete rupture (Grade 3); no lesion was considered to be Grade 0. Joint effusion and ATFl were the most common lesions whereas the TAmt lesion was the least frequent: JE approximately ATFl > SPmt approximately LPmt > LFGTmt approximately CFl approximately TAmt. Both US and MR were equally sensitive in detecting the presence (or absence) of the mt&l ankle injury, whereas US was less specific than MR in detecting G3 injury.