How do chondromalacia and patellafemoral syndrome differ?

Definition: Patellofemoral chondromalacia is a diagnosis given to the wear on the patella and trochlea (groove) cartilage. It is diagnosed most commonly when seen at surgery, or sometimes when diagnosed with imaging. When we cannot see the cartilage, we often call the disorder "patellofemoral pain syndrome". It's the difference between a physical diagnosis and a symptomatic diagnosis.

Chondromalacia: Agree with other answers. However, simply put: they are the same thing.

Basically the same: Chondromalacia patella (runners knee) is due to overload of the patellofemoral joint (knee cap against the end of the thigh bone). Running caused high forces in this portion of the joint. So does arising from a chair, going up/down stairs. Treatment consists of activity modification, ice, anti-inflammatory meds and therapy aimed at flexibility and strengthening, especially of your core.