Special Programs

The Motion Analysis Laboratory

The clinical mission of the Motion Analysis Laboratory of Shriners Hospitals for Children—Greenville is to carefully observe and measure the way our patients move; to understand how and why they move differently from children without movement problems; to recommend treatment plans;and to evaluate how well those recommendations improve their function. Although just about any of movements can be analyzed, most commonly, patients are referred to a motion analysis laboratory by a physician to assess and examine the patient’s walking or gait problems.

The clinical gait analysis require an experienced, multidisciplinary team comprised typically of physicians, engineers, physical therapists and kinesiologists. A variety of data and information is collected by the team and used in each clinical assessment:

1. The patient and other family members are interviewed by the staff to obtain the patient’s medical history and to better understand their perspective on their walking problems. Standardized survey forms are often used to better characterize the patient’s walking impairment.
2. Video recordings of the patient are made to provide an overall picture of their walking ability.
3. The patient is assessed on an examination table to appreciate the patient’s strength and ability to control their muscles and bend their joints. In addition, the team notes any bones in the leg that have been twisted or deformed through growth or inappropriate muscle activity.
4. The patient is then equipped with highly reflective spheres or markers and muscle sensors (called electromyographic electrodes). The patient walks along a level pathway and is monitored by 12 special motion cameras (that measure the movement of the reflective markers) and 2 force platforms (that measure how hard she/he is pushing on the ground). The patient might also walk on a foot pressure platform that measures how the pressure under the foot is distributed. All of these signals (from the motion cameras, force platforms, muscle sensors, foot pressure platform) are sent to the central data collection computer in the lab. These signals are then processed by the operator to produce the information used by the team for clinical decision making, including
• Kinematics: graphs that show how different parts of the patient’s body and the joints of their legs are bending and moving
• EMG (electromyography): graphs that show when leg muscles are active or “firing,”
• Kinetics: graphs that show the torque produced by muscles that drive and control joints
• Foot pressure: graphs that show how the force or pressure is distributed under the foot while walking
5. The patient may then be asked to walk while the air that he/she exhales is measured. This metabolic energy assessment documents the amount of energy that the patient must use in order to walk.
6. The team meets to review and interpret this gathered data and to explore and recommend treatment strategies, including bracing (orthoses), physical therapy, medications or surgery.