Chondral Delamination on MRI has a very specific appearance and is important to recognise as it indicates further chondral loss is likely to occur.

What is it? Chondral delamination is when cartilage separates and lifts off from its attachment with the cortex.

Why is it important? It can progress to complete loss of cartilage in that region.

Location: Most commonly seen in knee and ankle. Other joints uncommon.

What does it look like?

• Cartilage is elevated from the underlying subchondral bone

• Rim of high signal T2 ( fluid) between subchondral bone and cartilage

• Can be associated with an area of full thickness cartilage loss or can be isolated and surrounded by normal cartilage

Image above demonstrates rim of high signal fluid between elevated cartilage and subchondral bone at patella apex. Delamination is in continuity with a region of full thickness cartilage loss.

Progressive increase in cartilage loss: Commencing in July 2013 with afull thickness chondral fissure and early delamination to May 2015 Widening of area of chondral loss in fissure and increasing delamination to Jan 2016 where delamination has converted to larger area of full thickness cartilage loss.

Image above demonstrates rim of high signal fluid between elevated cartilage and subchondral bone in ankle