Chondromalacia patellae: Cartilaginous lesions of the patella in the setting of anterior knee pain

Introduction: Chondromalacia patellae (CP) is common among patients with anterior knee pain (AKP), characterized by softening and deterioration of the patellar cartilage. Although the exact etiology is unknown, risk factors include lower extremity muscle weakness, obesity, and female sex. Further, patellar maltracking may play a role in developing CP. Treatment algorithms for CP remain vague and inconsistent as the significance of the diagnosis remains in question. Initial treatment is typically nonoperative with various adjunct modalities. However, surgery may have a role for recalcitrant cases. Objectives: Although CP is a common diagnosis, there is still much to be learned about the significance of this diagnosis and subsequent treatment strategies. Knowledge of this will help to guide providers moving forward. Methods: The authors completed a thorough literature search of available published work through December 31, 2021, discussing CP and its relationship with AKP, and distilled this information into current concepts regarding history, diagnosis, treatment, and future directions. Results: Although much is still unknown about the significance and best treatment strategy for patients with AKP pain and CP, it is likely that in many cases chondromalacia is a finding in the presence of AKP, rather than the cause of the AKP. Conclusions: More work must be done to fully elucidate the underlying causes of CP. However, some of these cases are likely related to subtle maltracking and perhaps can be surgically corrected. In most cases, extensive nonoperative measures and searching for other causes of AKP is most prudent.