MRI
Scarring and oedema within the sinus tarsi with poorly defined sinus tarsi ligaments (cervical ligament and interosseous talocalcaneal ligament) and inferior extensor retinaculum. Synovitis of the posterior subtalar joint. Os trignonum with preserved marrow signal and only low grade adjacent synovitis making symptomatic posterior ankle impingement unlikely. There are features of anterolateral ankle impingement with bony spurring and localised synovitis. Mild scarring of the medial and lateral ankle ligaments without complete tear.