center of gravity within the base of support. Children with hemiplegia may not be able to side sit on the involved side because of an inability to elongate or rotate the trunk. They may be able to side sit only if they are propped on the involved arm, a maneuver that is often impossible. Because weight bearing on the involved side is a general goal with any person with hemiplegia, side sitting is a good position to work toward with these children (Intervention 5-21).
Actively working into side sitting from a four-point or tall- kneeling position can be therapeutically beneficial because so many movement transitions involve controlled trunk rota- tion. Advantages of using the four-point position to practice this transition are that some of the weight is taken by the arms and less control is demanded of the lower extremities. As trunk control improves, you can assist the child in moving from tall-kneeling on the knees to heel sitting and FIGURE 5-12. Sitting postures. A, Long sitting. B, Ring sitting. C, Tailor sitting.
finally from tall-kneeling to side sitting to either side. From tall-kneeling, the base of support is still larger than in stand- ing, and the arms can be used for support if needed.
Children with disabilities often have one preferred way to sit, and that sitting position can be detrimental to lower extremity development and the acquisition of trunk con- trol. For example, W sitting puts the hips into extreme inter- nal rotation and anteriorly tilts the pelvis, thereby causing the spine to be extended (see Figure 5-3, A). In this position, the tibias are subjected to torsional factors that, if sustained, can produce permanent structural changes. Children with low postural tone may accidentally discover this position by
pushing themselves back between their knees. Once these children “discover” that they no longer need to use their hands for support, it becomes difficult to prevent them from using this posture. Children with increased tone in the hip adductor group also use this position frequently because they lack sufficient trunk rotation to move into side sitting from prone. Behavior modification has typically been used to attempt to change a child’s habit of W sitting. Some chil- dren respond to verbal requests of “sit pretty,” but often the parent is worn out from constantly trying to have the child correct the posture. As with most habits, if the child can be prevented from ever discovering W sitting, that is optimal. Otherwise, substitute another sitting alternative for the potentially deforming position. For example, if the only way the child can independently sit on the floor is by W sitting, place the child in a corner chair or other positioning device that requires a different lower extremity position.
Adaptive Seating
Many positions can be used to facilitate movement, but the best position for activities of daily living is upright sitting. How that posture is maintained may necessitate caregiver assistance or adaptive equipment for positioning. In sitting, the child can more easily view the world and can become more interested in interacting with people and objects within the environment. Ideally, the position should allow the child as much independence as possible while main- taining safety. Adaptive seating may be required to meet both these criteria. Some examples of seating devices are shown in Figure 5-15. The easier it is to use a piece of adap- tive equipment, the more likely the caregiver will be to use it with the child.
FIGURE 5-13.Sacral sitting. (From Burns YR, MacDonald J. Physiotherapy and the Growing Child. London, WB Saunders, 1996.)
A B
Children without good head control often do not have sufficient trunk control for sitting. Stabilizing the trunk alone may improve the child’s ability to maintain the head in midline. Additionally, the child’s arms can be brought forward and supported on a lap tray. If the child has poor head control, then some means to support the head will have to be incorporated into the seating device (see Figure 5-4). When sitting a child with poor head and trunk control, the child’s back must be protected from the forces of gravity, which accentuate a forward flexed spine. Although children need to be exposed to gravity while they are in an upright sitting position to develop trunk control, postural deviation can quickly occur if muscular control is not sufficient.
Children with low tone often demonstrate flared ribs (Figure 5-16) as a result of an absence of sufficient trunk muscle development to anchor the rib cage for breath sup- port. Children with trunk muscle paralysis secondary to myelodysplasia may require an orthotic device to support the trunk during sitting. Although the orthosis can assist in preventing the development of scoliosis, it may not totally prevent its development because of the inherent muscle
imbalance. The orthosis may or may not be initially attached to lower extremity bracing.
Cristaralla (1975) compared the effect on children with cerebral palsy of sitting on a bolster seat versus a child’s chair. She found that sitting on a bolster seat allowed a more vertical position of the child’s pelvis than did sitting on the child’s chair. The bolster seat kept the child’s hips and knees flexed to 90 degrees. In addition, sitting astride a bolster puts the child’s legs in external rotation and can thus decrease adductor muscle tone. A bolster chair is depicted in Figure 5-15, B. Sitting on a chair with an anteriorly inclined seat, such as that found in the TherAdapt posture chair (TherAdapt Products, Inc., Bensenville, IL) (see Figure 5-15, A), facilitated trunk extension (Miedaner, 1990). Dilger and Ling (1986) found that sitting a child with cere- bral palsy on a posteriorly inclined wedge decreased her kyphosis (Intervention 5-22). Seating requirements must be individually assessed, depending on the therapeutic goals. A child may benefit from several different types of seating, depending on the positioning requirements of the task being performed.
Adjustable-height benches are an excellent therapeutic tool because they can easily grow with the child through- out the preschool years. They can be used in assisting chil- dren with making the transition from sitting to standing, as well as in providing a stable sitting base for dressing and playing. The height of the bench is important to consider relative to the amount of trunk control demanded from the child. Depending on the child’s need for pelvic sup- port, a bench allows the child to use trunk muscles to maintain an upright trunk posture during play or to prac- tice head and trunk postural responses when weight shifts occur during dressing or playing. Additional pelvic sup- port can be added to some therapeutic benches, as seen in Figure 5-2. The bench can be used to pull up on and to encourage cruising.
Side-Lying Position
Side lying is frequently used to orient a child’s body around the midline, particularly in cases of severe involvement or when the child’s posture is asymmetric when he is placed either prone or supine. In a child with less severe involve- ment, side lying can be used to assist the child to develop control of flexors and extensors on the same side of the body. Side lying is often a good sleeping posture because the caregiver can alternate the side the child sleeps on every night. For sleeping, a long body pillow can be placed along the child’s back to maintain side lying, with one end of the pillow brought between the legs to separate them and the other end under the neck or head to maintain midline orientation. Lower extremities should be flexed if the child tends to be in a more extended posture. For class- room use, a commercial sidelyer or a rolled-up blanket (Intervention 5-23) may be used to promote hand regard, midline play, or orientation.
INTERVENTION 5-21 Encouraging Weight Bearing on the Hemiplegic Hip
Place the child in side sitting on the hemiplegic side. Elevation of the hemiplegic arm promotes trunk and external rotation elongation.
FIGURE 5-15. Adaptive seating devices. A, Posture chair. B, Bolster chair. (A, Courtesy of TherAdapt Products, Inc., Bensenville, IL; B, courtesy of Kaye Products, Inc., Hillsborough, NC.)
FIGURE 5-16. Rib flare. (From Moerchen VA: Respiration and motor development: A systems perspective. Neurol Rep 18:9, 1994. Reprinted from the Neurology Report with the permission of the Neurology Section, APTA.)
INTERVENTION 5-22 Facilitating Trunk Extension
Sitting on a posteriorly inclined wedge may facilitate trunk extension.
Positioning in Standing
Positioning in standing is often indicated for its positive phys- iologic benefits, including growth of the long bones of the lower extremities. Standing can also encourage alerting behav- ior, peer interaction, and upper-extremity use. The upper extremities can be weight bearing or free to move because they are no longer needed to support the child’s posture. The upright orientation can afford the child perceptual opportuni- ties. Many devices can be used to promote an upright stand- ing posture including prone and supine standers, vertical standers, standing frames, and standing boxes.
Prone standers support the anterior chest, hips, and ante- rior surface of the lower extremities. The angle of the stander determines how much weight is borne by the lower extremities and feet. When the angle is slightly less than 90 degrees, weight is optimal through the lower extremities and feet (Aubert, 1999). If the child exhibits neck hyperexten- sion or a high guard position of the arms when in the prone stander, its continued use needs to be reevaluated by the supervising physical therapist. Use of a prone stander is indicated if the goal is physiologic weight bearing or hands- free standing.
Supine standers are an alternative to prone standers for some children. A supine stander is similar to a tilt table, so the degree of tilt determines the amount of weight borne by the lower extremities and feet. For children who exhibit too much extension in response to placement in a prone stander, a supine stander may be a good alternative. However, postural compensations develop in some children with the use of a supine stander. These compensations include kyphosis from trying to overcome the posterior tilt of the body. Asymmetric neck postures or a Moro response may be accentuated because the supine stander perpetu- ates supine positioning. Use of a supine stander in these situations may be contraindicated.
Vertical standers support the child’s lower extremities in hip and knee extension and allow for complete weight bear-
ing. The child’s hands are free for upper-extremity tasks such as writing at a blackboard (Intervention 5-24). The child con- trols the trunk. The need to function within different envi- ronments must be considered when choosing adaptive equipment for standing. In a classroom, the use of a stander is often an alternative to sitting, and because the device is adjustable, more than one child may be able to benefit from its use. Continual monitoring of a child’s response to any type of stander should be part of the physical therapist’s peri- odic reexamination of the child. The physical therapist assis- tant should note changes in posture and abilities of any child while using any piece of adaptive equipment.
Positioning in upright standing is important for mobility, specifically ambulation. Orthotic support devices and walk- ers are routinely used with young children with myelodys- plasia. Ambulation aids can also be important to children with cerebral palsy who do not initially have the balance to walk independently. Two different types of walkers are most frequently used in children with motor dysfunction. The standard walker is used in front of the child, and the reverse posture control walker is used behind the child. These walk- ers can have two wheels in the front. The traditional walker is then called a rollator. Difficulties with the standard walker include a forward trunk lean. The child’s line of gravity ends up being anterior to the feet, with the hips in flexion. When the child pushes a reverse walker forward, the bar of the walker contacts the child’s gluteal muscles and gives a cue to extend the hips. Because the walker is behind the child, the walker cannot move too far ahead of the child. The reverse walker can have two or four wheels. In studies conducted in children with cerebral palsy, use of the reverse walker (Figure 5-17) resulted in positive changes in gait and upright posture (Levangie et al., 1989). Each child needs to be evaluated on an individual basis by the physical therapist to determine the appropriate assistive device for ambulation. The device should provide stability, safety, and an energy-efficient gait pattern.
FUNCTIONAL MOVEMENT IN THE CONTEXT