Left knee pain

A 14-year-old teenager arrives at the office complaining of left knee pain that has persisted for six months. She mentions having a catching and popping sensation as she runs. She plays many sports and is quite active. With no relief in her pain, she underwent four months of conservative treatment, which included activity modification and physical therapy. Physical examination reveals no knee effusion in the patient. However, when she moves, she feels a popping feeling caused by patellofemoral compression. Magnetic resonance imaging (MRI) is unremarkable for any soft tissue damage. However, a thicker band of tissue can be seen in an intraoperative arthroscopic picture situated between the patella and medial femoral condyle.