What is ADHD? ADHD (attention deficit-hyperactivity disorder) affects both adults and school-aged children. Symptoms include restlessness, difficulty paying attention, and hyperactivity. The causes of ADHD are unknown, however factors such as diet, environment and genetics may contribute to symptoms.
The knee muscles control how the knee joint and patella move. There are two main groups of muscles, the quadriceps and the hamstrings, as well as a small muscle behind the knee (popliteus).
Behind knee pain is discomfort or soreness behind the knee joint. It may occur with or without movement and can be severe enough to limit movement. People may describe behind knee pain as discomfort, inflammation, increased warmth or burning, soreness, stiffness, or pain. Behind knee pain is a common sign of a Bakerâs cyst, which is a buildup of synovial fluid behind the knee.