Figure 7.

Small cartilaginous exostosis at the medial distal femur of the right knee.

Coronal FS T2-WI (A) demonstrates a focal contour deformation of the medial distal femur with a small overlying hyperintense cartilage cap (black arrow). Plain film (B) confirms a small sessile cartilaginous exostosis (white arrow), which was causing symptoms due to friction with the overlying vastus medialis muscle. This finding was initially overlooked and the patient’s complaints were attributed to meniscal degeneration (which was in retrospect not responsible for the patient’s symptoms). This case also illustrates the usefulness of correlation of MRI with other imaging modalities such as plain films.