Remember not to misdiagnose the normal irregular ossification of the femoral condyles as stage I osteochondral defect, especially when using ultrasound; MR imaging is helpful in distinguishing this normal variant.
Dynamic ultrasound scan of the anterior aspect of the lateral femoral condyle of a young football player.
Sagittal Ge-Stir and T1 weighted Mri of the same patient (0.3 Tesla). The overlying articular cartilage is intact.
Hello! Thanks for this article. One question: when using ultrasound the principle is “see something say something”? If we see something wrong (like in your case) we must always call for an MRI (to distinguish between osteochondral defect and irregular ossification)? Or if the cartilage is intact and the patient is young we can skip the MRI?
Hallo Chandra, thank you for this question. Irregular ossification of the distal femoral epiphysis and osteochondral defect can have a similar appearance also with Mri imaging; as you probably know ultrasound imaging has high sensitivity but less specificity on the cortical bone, so I suggest you to always perform an Mri study to better evaluate the cartilage integrity and eventual underlying bone oedema; moreover in this case the young patient had a painful clinical presentation so an inaccurate assessment of this patient’s condition can lead to unnecessary immobilisation.
Thanks!