Patellofemoral Syndrome

Overview


Plain-Language Overview

Patellofemoral Syndrome is a common knee condition that affects the joint where the kneecap (patella) meets the thigh bone (femur). It involves pain around or behind the kneecap, especially during activities like climbing stairs, squatting, or sitting for long periods. This condition is related to the muscles, tendons, and cartilage around the knee, which can become irritated or misaligned. The main health impact is knee pain that can limit movement and daily activities. It often occurs in young adults and athletes but can affect anyone. The discomfort usually worsens with repetitive knee bending or prolonged sitting. Understanding this condition helps explain why the knee feels sore or unstable during certain movements.

Clinical Definition

Patellofemoral Syndrome is characterized by anterior knee pain resulting from abnormal tracking or increased stress on the patellofemoral joint. The core pathology involves malalignment or imbalance of the extensor mechanism, leading to irritation of the articular cartilage or surrounding soft tissues. Common causes include overuse, muscle weakness (especially of the quadriceps and hip abductors), biomechanical abnormalities, and patellar maltracking. It is a frequent source of chronic knee pain in adolescents and young adults, particularly athletes. The syndrome is clinically significant due to its impact on mobility and potential progression to chondromalacia patellae or early osteoarthritis. Diagnosis is primarily clinical, supported by exclusion of other causes of knee pain. Imaging may show subtle changes but is often normal in early stages.

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