The Jesse Brown VA Medical Center Motion Analysis Research Laboratory

JBVAMC-MARL has a digital video subsystem consisting of two digital camcorders, a digital media recorder (DMR), a monitor, and a video-editing board used for recording split-screen displays of two simultaneous views of research subjects during experiments.

JBVAMC-MARL uses a Cosmed K5 Portable Metabolic Measurement System (Cosmed, Rome, Italy) for collecting energy expenditure data during activity and a Cosmed Sport Treadmill (T170) with a large belt surface, safety harness, incline/decline capabilities, and adjustable handrails.

JBVAMC-MARL has a Biodex Balance System SD (Biodex, Shirley, NY) used to evaluate dynamic balance and fall risk. The system is used to assess a subject’s neuromuscular control by quantifying their ability to maintain dynamic single or double leg postural stability on either a static or unstable surface. The system allows researchers to measure a subject’s ability to maintain their center of balance, their ability to move and control their body center of mass, and their ability to remain upright and balanced on unstable surfaces.

JBVAMC-MARL is equipped with a custom instrumented treadmill (N-Mill, MotekForce Link, Culemborg, the Netherlands) that can deliver augmented reality through projections onto the treadmill belt, real-time feedback through a monitor based on instantaneous kinetic and kinematic measurements, and walking perturbations. The treadmill is also capable of simulating incline and decline walking while subjects are wearing an overhead harness. 

A gait analysis is an experiment to record data about the way a person walks. Instrumentation included in a basic gait analysis includes a high-speed digital motion capture system, force platforms, digital video recordings and digital photos. Cameras track reflective markers that are placed on various anatomical landmarks on the participant. The participant is then asked to walk along a 10-meter walkway a minimum of five times at varying speeds. Manual muscle testing using a handheld dynamometer can be performed on the participant’s lower limbs to assess muscle strength. A goniometer is used to measure the flexibility and range of motion of the hip, knee and ankle joints. Participation for an able-bodied individual takes approximately two hours. Participation for a person with a physical impairment usually takes longer. 

Electromyography (EMG) is a technique used to measure muscle activity. Surface electrodes are attached to the skin over selected muscles using double-sided, non-allergenic tape. EMG is conducted in conjunction with a gait analysis. Preparation time for the subject will increase approximately 45 minutes, in addition to the setup/preparation time required for a gait analysis without EMG. 

There are two types of pressure measurements available, either in-sole pressure measurement or in-socket pressure measurement. In-sole pressure analysis involves measuring the pressure applied to the plantar surface of the foot using instrumented insoles placed between the foot and the shoe. Pressure analysis of the plantar surface of the foot can be conducted as a stand-alone procedure or in conjunction with a gait analysis. Participation time for the subject in a stand-alone pressure analysis lasts approximately one hour. If conducted in conjunction with gait analysis, preparation time for the subject will increase by approximately 30 minutes, in addition to the setup/preparation time required for a gait analysis without in-sole pressure.

If the participant wears a prosthesis, instrumented sensors are used to measure the pressure between the residual limb and the socket interface (in-socket pressure measurement). In-socket pressure measurement is conducted only in conjunction with a gait analysis. Preparation time for the subject will increase by approximately one hour, in addition to the set/up preparation time required for a gait analysis without pressure. 

Conducted in conjunction with a gait analysis, additional reflective markers are placed along the spine and on the head to measure spinal motion while walking or in a static standing position. Preparation time for the subject with the spinal markers will increase by approximately 30 minutes, in addition to the setup/preparation time required for a standard gait analysis. 

An energy expenditure test is conducted to analyze the air that is exhaled while walking. The test can be done as a stand-alone procedure or in conjunction with a gait analysis. A mask that covers the nose and mouth is fitted to the participant. Additional equipment, including a battery pack and the sampling device, is harnessed to the participant. The test protocol consists of three stages: 1) pre-exercise resting energy expenditure, 2) walking energy expenditure, and 3) post-exercise resting energy expenditure. During the pre- and post-exercise phases, the participant sits quietly for approximately 5 minutes in each phase. During the walking phase, the participant walks for 10 minutes at a self-selected speed on a treadmill. Preparation time for the subject is approximately 30 minutes. Participation time for the subject is approximately 45 minutes.

All of the measurement systems in JBVAMC-MARL are integrated to synchronize the collection of data, providing a comprehensive overview of the particular human movement activity. A primary goal of JBVAMC-MARL is to provide researchers, and ultimately clinicians, with more complete knowledge and a better understanding of the mechanical interactions that occur between humans and P&O systems. Knowledge derived from these systems can contribute to better P&O fitting and improve the quality of life for individuals who use these devices.