MR Arthrography MR arthrography has been found to be an accurate method for assessing both anterolateral and anteromedial impingement with the advantage of joint capsule distention by intra-articular contrast injection [68,69]. US One study involving anterolateral ankle impingement compared US to arthroscopic findings. The study found US had a sensitivity and specificity of 77% and 57%, respectively [70]. US also showed abnormal soft tissues in anterolateral impingement, with a reported accuracy of 100% in one study [72]. MRI Studies on the accuracy of MRI in diagnosing anterolateral impingement syndrome have drawn varying conclusions, which may be related to varying MRI magnet strengths and inconsistent protocols [73]. Comparing MRI with surgical findings, studies have shown sensitivities between 75% to 83% and specificity between 75% to 100% for the diagnosis of anterolateral impingement [73,74]. One study found that, when compared with arthroscopy, fat-suppressed, IV contrast-enhanced, 3-D gradient- recalled echo imaging was sensitive for the evaluation of synovitis of the ankle associated with trauma (92%), whereas it was specific for soft-tissue impingement evaluation (97%) when the ankle was divided into four compartments: the anterolateral gutter, anteromedial gutter, anterior recess, and posterior recess [75]. MRI is useful in confirming the diagnosis, evaluating patients with an uncertain clinical diagnosis, and planning surgery. Additionally, it can help exclude other pathologic entities that may mimic or coexist with impingement syndromes. However, MRI features supportive of impingement may be present in asymptomatic individuals, and an accurate diagnosis requires careful correlation of imaging features findings with clinical findings [76]. There are only limited reports on the use of MRI for the other forms of ankle impingement syndrome, so its accuracy in these conditions is not well established [62,64,67,68].
Chronic Ankle Pain. MR Arthrography MR arthrography has been found to be an accurate method for assessing both anterolateral and anteromedial impingement with the advantage of joint capsule distention by intra-articular contrast injection [68,69]. US One study involving anterolateral ankle impingement compared US to arthroscopic findings. The study found US had a sensitivity and specificity of 77% and 57%, respectively [70]. US also showed abnormal soft tissues in anterolateral impingement, with a reported accuracy of 100% in one study [72]. MRI Studies on the accuracy of MRI in diagnosing anterolateral impingement syndrome have drawn varying conclusions, which may be related to varying MRI magnet strengths and inconsistent protocols [73]. Comparing MRI with surgical findings, studies have shown sensitivities between 75% to 83% and specificity between 75% to 100% for the diagnosis of anterolateral impingement [73,74]. One study found that, when compared with arthroscopy, fat-suppressed, IV contrast-enhanced, 3-D gradient- recalled echo imaging was sensitive for the evaluation of synovitis of the ankle associated with trauma (92%), whereas it was specific for soft-tissue impingement evaluation (97%) when the ankle was divided into four compartments: the anterolateral gutter, anteromedial gutter, anterior recess, and posterior recess [75]. MRI is useful in confirming the diagnosis, evaluating patients with an uncertain clinical diagnosis, and planning surgery. Additionally, it can help exclude other pathologic entities that may mimic or coexist with impingement syndromes. However, MRI features supportive of impingement may be present in asymptomatic individuals, and an accurate diagnosis requires careful correlation of imaging features findings with clinical findings [76]. There are only limited reports on the use of MRI for the other forms of ankle impingement syndrome, so its accuracy in these conditions is not well established [62,64,67,68].