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).
The popliteus is a small muscle that runs behind the knee. Due to its small size compared to the hamstrings above and the calf below, it is often overlooked in knee and lower leg injuries. It also isn't a very strong muscle, which adds to its relative obscurity. It is, however, of paramount importance to athletes. The popliteus has three basic motions.