The 3D analysis we perform includes several calculations, including kinematics, kinetics and stride characteristics. These tests allow us to create a computer-generated model of your child’s skeleton to more accurately assess their movement challenges.
The physical therapist will ask your child to walk a line the length of the room. At first, your child will complete this barefoot and, if possible, without orthotics or assistive devices. This helps us capture their most natural walking form. Then, if your child has an assistive device, the therapist will ask them to walk with it. Motion capture cameras around the room will capture your child’s movements in 3D from a 360-degree view.
What is motion capture?
Motion capture records movement using special cameras and computer programs. It’s the same technology used to make some of your child’s favorite animated movie characters and video games.
3D motion kinematics: A picture of walking
Our 3D motion capture system creates a 3D picture of how your child moves and walks. Small markers are placed on different bony landmarks on the body. These markers are reflective balls — similar to small ping pong balls — that stick to your child’s skin. Markers are typically placed on the pelvis and legs but may include the midsection and arms if necessary.
Cameras throughout the room track these markers on your child as they walk, capturing the data needed to create a 3D picture. This test is done as naturally as possible, barefoot with no assistive devices. Removing the markers is similar to removing a small bandage or sticker.
We compare your child’s walking pattern to that of a typical child. This helps us identify unusual patterns of motion and measure how different those patterns of motion are.
3D motion kinetics: Measuring the force of walking
In addition to the markers used to study motion kinematics, we also study motion kinetics, or the physical force that produces joint movement when walking. Custom force platforms embedded into the floor measure the force produced when a foot comes in contact with them.
Stride characteristics: Measuring how your child walks
“Stride” is essentially a cycle from the initial contact of one foot with the ground to the next time the same foot makes contact. During this part of the analysis, we measure your child’s stride characteristics, like average walking speed, cadence, stride length, symmetry and more. Our staff compares your child’s measures to that of a typical child to identify abnormal characteristics.