Bruce Wigness’s research while affiliated with Lite Tech, Inc. and other places

Supporting body weight and balance control are foundations of our ability to move and function independently. However, neurological disease, injury, and aging often threaten these prerequisites of functional independence, leading to a decrease in quality of life. In the United States alone, 7.5 million individuals have survived stroke, traumatic brain injury (TBI), or spinal cord injury (SCI), and over a million new patients are diagnosed every year [1–2]. To improve gait function in these patient populations, partial body weight-supported gait training is a widely-used rehabilitation therapy. In general, the therapeutic quality of partial body weight-supported gait training is directly proportional to the amount of time patients are able to tolerate an upright posture (either standing or walking). To achieve an upright posture, therapists must first attach a support system (e.g., gait belt, harness lift system, exoskeleton), then several therapists must assist the patient into a standing position. Depending on the patient’s level of impairment, several therapists may also be needed to support and assist the patient while standing and walking, then again to remove the support system at the end of therapy. Accordingly, multiple therapists are often needed to provide a small quantity of upright physical therapy time with standard support systems. Furthermore, use of standard support systems can be uncomfortable and fatiguing for the patient, further reducing their actual therapeutic treatment time [3].

In the U.S. alone, 7.5 million individuals have survived stroke, traumatic brain injury, and spinal cord injury, and over a million new patients are diagnosed every year [1]. Most of these patients will need gait rehabilitation. Body weight supported gait training is a widely used rehabilitation therapy to improve gait function [2]. Commonly, a physical therapist provides assistance using a gait belt to support the patient. Sometimes two or three therapists may be needed for severely impaired patients. Bodyweight supported treadmill training uses a harness attached to an overhead lift to support body weight [2], however harness systems often cause discomfort and may take significant time to set up and take down. Lite Run Corporation has developed a system for the treatment of patients with gait and balance difficulties that uses differential air pressure inside a specially designed suit to reduce up to 50 percent of a patient’s body weight. The suit facilitates patient ambulation using technology like that in astronaut spacesuits to achieve comfort and flexibility. Potential benefits include longer therapy sessions due to greater comfort and greater unweighting, as well as the therapeutic benefits of being upright and walking for subjects unable to stand independently. The suit is used in conjunction with the Gait Trainer device shown in Figure 1 which provides air pressure to the suit and support for the patient. Gait Trainer features include: 1) electro-mechanical and pneumatic controls to support the suit and patient when rising from sitting to standing and ambulating during therapy — so that a single therapist can safely transfer a patient from a wheelchair and practice gait therapy; 2) an open design that permits access to patient’s body and legs by the therapist; 3) a compact profile that provides easy maneuverability; 4) a “base spread” function that permits positioning close to a patient when seated in wheel chair, bed or therapy table. Together these features provide safety and stability for the patient and reduced physical burden on the therapist. The objectives for the current study were to establish the safety and feasibility of the Gait Trainer, validate user design requirements, and to test the hypothesis that the rate of perceived exertion when using the device is significantly less than during unaided walking therapy.