History

In 1906, for the first time, pathological changes in the patellar cartilage were reported by Budinger et al. Then, Kelly et al described these pathological changes as chondromalacia patellar (CMP). Originally, the word "chondromalacia" stemmed from Greek words. Chondros means cartilage, and malakia means softening. In general, chondromalacia (sick cartilage) is an affliction of the hyaline cartilage coating of the articular surfaces of the bone. CMP is when the posterior articular surface of the patella starts losing its density when in a healthy state and becomes softer with subsequent tearing, fissuring, and erosion of the hyaline cartilage. It is commonly recognized as involving the extensor mechanism of the knee and is accordingly often referred to as chondromalacia of the patella, patellofemoral syndrome, or runner's knee. The undersurface of the patella is covered with hyaline cartilage that articulates with the hyaline cartilage-covered femoral groove (trochlear groove). Post-traumatic injuries, microtrauma wear and tear, and iatrogenic medication injections can lead to chondromalacia development. Chondromalacia can occur in any joint and is especially common in those with trauma and deformities.