Post-operative Lite Run Study

Background Cerebral palsy (CP) refers to a group of disorders affecting movement and is
attributable to a non-progressive injury to the developing brain. CP is the most common cause
of physical disability in childhood with a prevalence of 3.1 - 3.6 per 1000 births. At this
prevalence, we estimate that over 300,000 children under 21 in the US have CP. Children with
CP have a variety of neuro-motor impairments including muscle weakness and abnormal muscle
tone that leads to progressive musculoskeletal impairments over time. These children
experience discomfort and limitations in functional mobility such as walking (ambulation)
that severely impact their quality of life. Surgical intervention is often used to improve
ambulation quality and quantity for children with cerebral palsy anytime from childhood into
adulthood. Depending on treatment goals, it is not unusual for an individual with cerebral
palsy to undergo surgery involving muscles, tendons, bones or nerves of the feet, ankles,
legs or hips. Two common surgical interventions for ambulatory children with cerebral palsy
include single event multilevel orthopedic surgery to correct muscle lengths and bone
alignment, and selective dorsal rhizotomy to decrease spasticity. Post-operative treatment
course varies depending on the child's condition, pre-operative functional level, and
specific surgical intervention selected to improve their particular deficiencies.
Post-orthopedic surgery, children may be non-weight-bearing for 2-6 weeks. After selective
dorsal rhizotomy, patients exhibit surgical site instability and significant trunk and leg
weakness. They are non-weight-bearing for 2-4 weeks post-surgically, and may begin to stand
and walk once cleared by the physician.

When beginning mobility training after orthopedic or selective dorsal rhizotomy surgery,
children typically demonstrate significant weakness and can experience fear, pain and anxiety
as they begin to move. One aspect of mobility that is a significant milestone for children
post-surgically is getting back up and walking. The process to get back up and walk is
facilitated by physical therapists and is termed "gait training" which includes the
components of moving from sit to stand, bearing weight through the lower limbs, taking steps,
and returning to a sitting position. Body weight-supported gait training is often used in
therapy for adults and children to ease the transition from non-weight-bearing back to being
able to walk at their previous level of gait function. Support during this transition may be
provided by a physical therapist using a gait belt, a harness system attached to an overhead
track or device to support body weight, or other assistive devices. Current body weight
support systems for gait training are not optimal. Also there are reports in the literature
of difficulties with harness discomfort and donning and doffing. An unpublished survey of
twelve physical therapists was conducted by a University of Minnesota PT student who was able
to identify 20 deficiencies in available devices for body weight supported gait training.
More than 50% of the therapists cited the following sub-optimal aspects from their
experiences:

- Therapist providing majority of the body weight support when using a gait belt takes
away from therapeutic touch for gait therapy

- Current harness devices cannot adjust the percent of how much support the device gives

- There is not sufficient therapeutic evidence for the efficacy of current body weight
support devices

- Current harness devices do not feel like they will help us prevent injury.

- Current body weight support devices only work in limited applications

Using physical therapist support for gait training without a body weight support device can
require multiple people to assist, result in fatigue, and has the potential of injury for the
therapist. In a survey of physical therapists working in rehabilitation facilities, 67%
reported musculoskeletal pain or discomfort within the past year. Half reported that patient
repositioning (49%) and gait training (47%) also caused or contributed to their pain. Another
study reports survey results of over 1,000 occupational and physical therapists. The survey
indicated that functional activities such as gait training and settings such as pediatric
rehabilitation were associated with injury. An ergonomic analysis of physical therapists
working in rehabilitation concluded that physical therapists are at high risk for work
related musculoskeletal injuries while performing sit-to-stand transfers and overground gait
training.

To improve gait training therapy for both therapist and patient and to reduce a therapist's
need to lift and support the body weight of a patient, Lite Run Inc. has developed the Lite
Run Gait Trainer (Lite Run). Lite Run is a new system for the treatment of patients with gait
and balance difficulties that uses differential air pressure inside a specially designed
lower body suit to effectively reduce up to 50 percent of a patient's body weight. The suit
is similar to a pair of pants in appearance and is as easy to don and doff as a pair of
pants. The suit uses technology like astronaut spacesuits to achieve comfort and flexibility
while providing a unique "unweighting" effect that facilitates patient ambulation from
sitting through taking steps. The suit is used in conjunction with the Lite Run Gait Trainer,
which provides air pressure to the suit and support for the patient.

Lite Run features include: (1) control for the amount of body weight support (up to 50% of
the patient's weight), (2) electro-mechanical and pneumatic controls for providing assistance
in transferring the patient from sitting to standing and ambulation, (3) an open design that
permits access to a patient's body and legs by the therapist, (4) a compact profile that
provides easy maneuverability, and (5) a "base spread" function that permits positioning
close to a patient when seated in a wheelchair, bed or therapy table.

Together, these features provide safety and stability for the patient and reduced physical
burden on the therapist while improving the gait training experience and potentially
preventing patient or therapist injury. The system also frees the therapist to focus on
skilled therapeutic activities because the patient is secure in the system.

Lite Run conducted a product demonstration and pediatric needs survey for six physical
therapists at Gillette Children's Specialty Healthcare. Current support devices used for
training include overhead harness supports, robotic systems, and harness gait trainers.
Therapists indicated that current devices can be uncomfortable, cause patients to "hang" on
the support, and limit natural motion during sit-to-stand and walking. Gait trainers and
walking devices provide trunk and pelvic support using a seat or harness, and are used with a
treadmill which can be both uncomfortable and scary for children right out of surgery.

Lite Run may have FDA listing as a Class I device by mid 2017 based on adult clinical
feasibility testing, and completion of independent agency testing and in-house evaluations. A
clinical safety and feasibility trial for adult patients was performed at the Rehabilitation
Center at North Memorial Medical Center, Robbinsdale, MN with 18 adults with a range of
neurological conditions.

Adult physical therapists participating in this trial have indicated the following:

- Lite Run is comfortable. Harnesses at the groin are uncomfortable for many patients.
Lite Run has the potential to decrease pain, and improve security, support, compression,
adjustability, and flexibility in combination with support. It provides improved
mobility during sit-to-stand. The device may allow the patient to get back up walking
sooner after surgery than if they were using another device.

- It is easy for therapists to use. Pants donning time is less than 5 minutes, and
requires two quick attach points to engage the patient into the device. It is easily
adjustable.

- It decreases the burden on the therapist. Because the device supports the patient's body
weight, therapists hands are free to provide cuing and facilitation rather than physical
support. It could prevent therapist injury particularly to the back. It is fall proof.

- The device is able to quantify the amount of support provided.

The results of this study indicated that there were no adverse events or safety issues from
using the system on adults. In addition to safety and feasibility testing, the following user
design requirements were tested: time to don liner and pants, transfer-in time, therapist's
access to patient, patient's arm mobility, hindrance of patient's stride, patient directed
steerability, brake stability, overall stability, sit-to-stand functionality, wheelchair
compatibility, sit-to-stand sufficiency, odometer acceptability, ease of use, and the
physical effort required by the PT. After training, all therapists were all able to operate
the Lite Run safely and independently. The device allowed them to use their hands to provide
skilled therapeutic maneuvers, as the device provided stability and patient unweighting. The
study demonstrated that the Lite Run is a safe system and shows potential for pediatric
application to improve the rehabilitation experience and outcomes. Therefore, continued
investigation regarding the feasibility of using the device in a post-operative pediatric
population using pediatric sized lower body pressure suits is warranted.

Inclusion Criteria:

- diagnosis of cerebral palsy, neurologic syndrome, chromosomal abnormalities, spina
bifida, or other neurological disorders

- age 4-17

- recent single event multilevel lower extremity orthopedic surgery or selective dorsal
rhizotomy

- referred for physical therapy for mobility/gait training to regain functional walking
and ambulation

Exclusion Criteria:

- Gross Motor Function Classification System levels I (walk and run in the community
with only limitations in balance, coordination and speed) and V (use wheelchair to
maintain sitting and for whole body mobility) prior to surgical intervention

- Subjects who are too large or too small to fit within the current Lite Run
pants/prototype. The minimum patient weight is 50 lbs. The maximum patient weight is
350 lbs.

- Subjects that do not have clearance for full weight-bearing at the first treatment
session