Knee

Knee pain is common at all ages.

Anterior knee pain is common, pain is worse on exercise and is more common in adolescents and relates to foot posture, leg alignment and hypermobility. 

• Osgood Schlatter's disease is common, especially in adolescent boys who are physically active (particularly those who play football or basketball).
• Chondromalacia Patellae is more common in adolescent girls and may associate with hypermobility, flat feet and genu valgum (knock knees).

Trauma in the knee can result in meniscal, or cruciate or collateral ligament injury. These injuries result after significant injury and there is likely to be bruising and even a swollen knee (haemarthrosis). The knee may lock or even be unstable. 

Osteochondritis dissecans may result in a loose fragment / body but usually results in a tender femoral condyle (usually the medial femoral condyle).

Knee pain may be referred from the hip.

Red flag conditions (Infection and malignancy) are important to exclude as part of the assessment.

Inflammatory arthritis commonly affects the knee.