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).
(1) In order to unlock the knee from extension, the popliteus muscle must work to initiate internal or external rotation. (4) The tibia must internally rotate slightly to allow for knee flexion in an open chain, and the femur must externally rotate for knee flexion in a closed chain.