Chondromalacia patellae which is also known as CMP is inflammation of the underside of the patella and softening of the cartilage. Chondromalacia patellae is a term sometimes treated synonymously with patellofemoral pain syndrome.
Chondromalacia can be divided into 4 grades by MRI, typically using fat saturated proton density sequences. This grading system is the modified Outerbridge grading system, which was devised for arthroscopy initially for assessment of chondromalacia patella, but then modified and extended for all chondral surfaces
Grade I: focal areas of hyperintensity with normal contour arthroscopically: softening or swelling of cartilage.
Grade II: blister-like swelling/fraying of articular cartilage extending to surface arthroscopically: fragmentation and fissuring within soft areas of articular cartilage.
Grade III: partial thickness cartilage loss with focal ulceration arthroscopically: partial thickness cartilage loss with fibrillation (crab-meat appearance).
Grade IV: full thickness cartilage loss with underlying bone reactive changes arthroscopically: cartilage destruction with exposed subchondral bone.
According to the statistics there are many risk factors for developing chondromalacia i.e Age, sex, flat feet, previous injury, activity level, arthiritis Patients with chondromalacia patellae usually present with anterior knee pain on walking up or down stairs. Additionally there may be knee pain when kneeling or squatting or after sitting for long periods of time. Knee stiffness, crepitus and effusions may also be present. In some cases, a history of patellar dislocation may be present.