Gait Trainers

What are the benefits of walking? They can be broken down into three different categories: physiological, psychological, and motor developmental.

The physiological benefits of standing are more pronounced with walking. The benefits to the 4 B's (blood, breathing, bone, and bowel) are enhanced due to movement and exercise made possible by gait trainers.

The bones and joints may be the most affected; weight bearing and movement are necessary for their proper development.

The Medical Need for Walkabouts for Non-Ambulatory CP Children:

All newborns have cartilaginous skeletons. Their bones mineralize with stress, and grow in the direction of stress. In a newborn the femoral shaft is straight without an angled neck connecting the ball end. The acetabulum and the offset angle of the neck of the femur to the shaft do not occur until there is weight bearing. The acetabulum does not fully form until there is weight bearing throughout the full range of motion of the femur.

Children with CP have damaged central nervous systems that effect motor control, often causing immobility. Steinberg states that immobilization has dramatic effects on the musculoskeletal system. It has been demonstrated that the immobilization of muscles and lack of weight bearing on bone causes bone demineralization and a true osteoporosis (1). Mazur et al showed that non-walkers
had five times the number of pressure sores and twice the number of fractures as walkers with the same disability (2). In 1959 Phelps published on 100 children with CP who had not borne weight before the age of 4 years, and compared them
to 100 normal and CP children who had. He found that about 25% of the children in the non-weight bearing group had coax-valga, compared to 3-4% in the weight- bearing group. He concluded that acquired dislocations of the hip in CP appeared
to result from coax-valga due to late weight bearing along with spasticity and contracture (3).

Enneking & Horowitz state that: "Muscles that are immobilized and remain in a shortened position or fixed position, become contracted. Eventually much of the muscle tissue is replaced by fibrous components and normal function cannot be restored. Many neuromuscular diseases predispose the patient to muscular contractures, including: CP, poliomyelitis, Duchenne's Muscular Dystrophy, and chronic degenerative diseases of the spinal cord. Prolonged muscular immobilization may have a direct effect on joints. Contractures of the joint capsule and surrounding muscle can cause a restriction in the range of motion of the joint. The lack of movement in the joint results in a lack of synovial fluid flow,
which will eventually lead to irreversible degenerative changes in the joint cartilage (4).

Karen Chad of the University of Saskatchewan concludes in her paper on "The effects of a weight-bearing physical activity program on bone density in children with spastic CP" that "It should be the therapeutic goal of health professionals to promote active standing and other forms of weight-bearing activity to decrease skeletal fragility and susceptibility to fracture in these groups." (5)
References:
(1) Steinberg, F.U.: The Immobilized Patient: Functional Pathology and Management pp17-21 (1980)
(2) Mazur et al: Bone & Joint Journal 71A, 56-61
(3) Phelps, Wm: Journal of Bone & Joint Surgery (Am). 1959; 41:440-448
(4) Enneking, W.F. and Horowitz, M.: Journal of Bone & Joint Surgery
54A:973 (1972)
(5) Karen E. Chad, PhD et al: Journal of Pediatrics; 1999; 135-115-7

Adjusting a Walkabout or Gait Master for Optimun Performance

These systems have many adjustable parameters and positioning accessories to help a user achieve a functional walking posture:

It is important to first assess the client's dominant reflexes, and postural support needs. If he/she has a dominant STNR the column tilt must be adjusted to attempt to neutralize the tendency to either strong extension or flexion. A forward tilt of 2-4 degrees generally works. The pelvis needs to be well secured so that forward thrust is limited. In most cases the shoulders need to be slightly ahead of the hips.
Fine tuning is often necessary, small changes can often make large improvements.

If the child's upper truck is posturally secure a "C" model having a double sling support will suffice. If it is weak a "D" model with an adjustable ring angled up to support the sternum will give shoulder girdle support making head control easier.
If shoulder girdle control is still a problem shoulder pads can be tried. If the child
has a correctable scoliosis, offset thoracic pads can be fitted to the column.

Although tilting the column can help breakup strong adduction at the hips you may need addition help. We have found that abduction cuffs and straps build strong adductors, and inhibit gait. We build an abduction seat that consists of a tapered seat with a heavily padded top and a bottom extension (skirt) that come down almost to the knees. In most cases it has worked very well. They are individually made, so accurate specs are important.

Head control: the Walkabouts are about the only device available with head arrays to support abnormal head posture. Many sizes and types of supports are available.
Specifying help is always available at 800-543-4769.

Mulholland Positioning Systems, Inc.
839 Albion Avenue
Burley, ID 83318
Ph: 800-543-4769 (800-KID-GROW), 208-878-3840
Fax: 208-878-4041
Email: info@mulhollandinc.com