Because a cartilage has a "sealing" layer of skin called Perichondrium around of it, an infection trapped inside it will cause inflammation : Results are and a "moderated" swelling, and a red ear which is often hot to the touch.
In rare cases, the infection can spread and reach the cartilage who swells seriously : This problem is called chondrosis or chondromalacia that defined as a softening or a loss of smooth cartilage. Swelling of this type will usually be hard to the touch and painful. Treating the infection quickly is essential, as problems can escalate very quickly.
The entry on Ear Collapse is an example of the result of Chondritis.