Diagnosis of anterolateral ankle impingement. Comparison between magnetic resonance imaging and clinical examination.

We reviewed 22 patients who had arthroscopic evaluations and preoperative magnetic resonance imaging studies of their ankles because of chronic anterolateral ankle pain after sprains. The ability of surgeons to use the initial clinical examination to predict arthroscopically confirmed anterolateral ankle impingement was compared with the ability to predict this condition using preoperative magnetic resonance imaging. The patient population consisted of 15 men and 7 women who had an average age of 28 years. Five patients (23%) were intercollegiate athletes and 17 patients (77%) were recreational athletes. All patients reported previous traumas to the involved ankles, and all were seen with chronic ankle pain. Clinical examinations were used to assess ankle pain, swelling, range of motion, and stability. Anterolateral ankle impingement was confirmed in 18 patients (82%) with arthroscopic examination. Clinical examinations had a sensitivity of 94% and a specificity of 75% for predicting impingement, and magnetic resonance imaging had a sensitivity of 39% and a specificity of 50%. The results of this study suggest that preoperative magnetic resonance imaging examination is not beneficial or cost-effective in the diagnosis of anterolateral ankle impingement; furthermore, its use may cause further delay in treatment.