How do sprinters run so fast? How do we use our muscles to recover from a fall? Can we design better prosthetics for amputees? Can we plan surgery for children with cerebral palsy? Narrator: OpenSim—Freely available computer software re-engineering the way we see movement. Movement comes naturally to most of us. We run. We ride bikes. We walk to work. But diseases that our affect muscles and bones make these simple motions not so simple. OpenSim provides scientists with a platform to understand motion. Scott Delp: OpenSim is a software program that let’s you create highly accurate models of humans and animals and how they move. Narrator: For example, we can model running, which requires dozens of muscles in coordination. Each muscle in the body generates its own force, pulling the bones it’s connected to closer together. As they are activated, other muscles generate different forces. Using what we know about physics, anatomy, and physiology we calculate all the different forces generated by all the different muscles as they are activated and deactivated at different times. This allows us to simulate and study many motions like walking or running. Delp: The goal is to have this common tool that we all use around the world to understand biomechanics of movement and to improve treatments for individuals who have physical disabilities. Kat: Cerebral Palsy is caused by an injury to the brain near birth. Problems with movement, coordination and walking as child grows up. Narrator: Many children walk in a crouch gait. Showing too much knee flexion, or bending. This pattern of walking is inefficient, and can lead to joint pain and degeneration over time. The hamstrings are the large group of muscles in the back of your thigh. In children with cerebral palsy, they often become contracted or too tight. One common treatment is a surgery to lengthen the hamstrings. This helps many children walk with a more efficient, upright posture. It’s difficult to figure out who will get better, and who won’t, just by watching a patient walk. Here in our gate lab, we do use hamstrings, muscle lengths, and velocities to help us make decisions about who should have a hamstrings lengthening surgery as part of the treatment for their crouch gait. Narrator: A doctor can use a computer model to determine the length of a patient’s hamstrings. This patient has hamstrings that are much shorter than normal when he walks, so he is a good candidate for surgery. After surgery, we see that indeed the patient is walking with a much more upright posture. Kat: So our end goal after any treatment, whether it’s surgery or therapy, is to help these kids walk better. So that they can play with their peers. So that they can run around the school yard at the end of the day. Narrator: Planning treatment for children with cerebral palsy is just one of the many applications of OpenSim. In Chicago, researchers are using modeling to help patients with spinal cord injuries regain the ability to reach, and pick up a pencil. In California and Florida, we’re learning about how knee joint loads might cause osteoarthritis. In London, simulations are being created to explore how a Tyrannosaurus Rex was able to run. And in Italy, engineers are using OpenSim to design better robots. OpenSim—freely available software re-engineering the way we see movement. Visit opensim.standford.edu today to learn how you can join the OpenSim community.