18 year male patient with right hip region pain

Radiograph of pelvis(1) shows sessile lesion likely arising from the medial aspect of right femoral neck. MRI was suggested for further evaluation. Coronal T1(2) demonstrates continuation of marrow into the lesion. Coronal and axial STIR images show thin hyperintense cartilage cap over the lesion with no associated marrow edema, fracture or bursitis.