The value of MR imaging in the diagnosis of the os trigonum syndrome

The objective of this study was to evaluate the value of magnetic resonance (MR) imaging in the diagnosis of the os trigonum syndrome. Sagittal and coronal spin echo MR sequences of the ankle were acquired along with sagittal images in both dorsiflexion and plantar flexion. Three consecutive patients presenting with posterior triangle pain were assessed. MR imaging delineated the anatomical site of the abnormality and demonstrated coexisting pathology in all patients. Flexion/extension MR images yielded additional information regarding the mobility of the os trigonum in one patient. MR imaging is the technique of choice for investigating the os trigonum syndrome. (orig./MG)