The 3D analysis we perform includes several calculations, including kinematics, kinetics and stride characteristics (specifically for gait). These tests allow us to create a computer-generated model of your child’s skeleton to more accurately assess their movement challenges.
For gait analysis, 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.
For a sports analysis, your child will perform squatting, jumping and running movements that may mimic how they perform in their sport.
Motion capture cameras around the room will record your child’s movements in 3D from a 360-degree view.
What is motion capture?
This is when your child gets to put on the "robot suit." It’s an interesting exercise where they perform again for the cameras, only this time they get to dress up.
Motion capture is the same technology used to make some of your child’s favorite animated movie characters and video games. It records movement using special cameras and computer programs. This provides us a more complete picture of your child’s movement.
3D motion kinematics: A picture of movement
Our 3D motion capture system creates a 3D picture of how your child moves and walks. We place small markers on different bony parts of the body. These markers are reflective balls — like small ping pong balls — that stick to your child’s skin. We typically place markers on the pelvis and legs but we may include the midsection and arms if necessary.
Cameras throughout the room track these markers on your child as they walk, squat or jump, capturing the data needed to create a 3D picture. We do this test as naturally as possible — barefoot for gait analysis and in athletic shoes for sports. Removing the markers is similar to removing a small bandage or sticker.
For a gait analysis, we compare your child’s walking pattern to other children. This helps us identify certain patterns of motion and measure how different those patterns are.
3D motion kinetics: Measuring the force of moving
In addition to 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 of a foot landing.
Stride characteristics: Measuring how your child walks in a gait analysis
Stride is a cycle from the first contact of one foot with the ground to the next time the same foot contacts the ground. 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 other children to identify potential health issues.
Isokinetic dynamometer: Measuring your child’s strength in a sports analysis
Isokinetic means constant speed. Our isokinetic dynamometer machine measures how hard your child’s muscles work as they move or how much force their muscles can generate. Your child will complete several repetitions of motion at different speeds while the machine measures how much force their muscles produce. This allows us to look for muscle strength weaknesses and imbalances. This test is only part of a sports analysis.
Plantar pressures: A picture of your footprint in a gait analysis
Plantar pressure measurements show us what parts of the feet are in contact with the ground and how weight is distributed as your child steps from one foot to the other. A special black mat embedded into the floor records the foot pressure distribution when a foot meets it. This data looks like a rainbow map of your child’s feet.