Enhancing Fitness, Adaptive Motor Function, and Participation of Children with Cerebral Palsy Classified in Levels IV and V

Keeping Current. © Robert J. Palisano & Karen Lally, 2007

This report will address adaptive motor function of children with cerebral palsy. Adaptive motor function enables performance of activities in daily life despite limitations in motor control of posture and movement. Adaptive motor function is accomplished through assistive technology and environmental modification and accommodation. The focus of this review is on children classified in levels IV or V on the Gross Motor Function Classification System (GMFCS) (Palisano et al., 1997). Children classified in levels IV and V need adult assistance for mobility and self-care most times throughout the day. The importance of wellness, physical fitness, and prevention of secondary complications for children with mobility limitations are discussed. Websites of manufacturers cited in the report are intended to provide readers pictures of assistive technology and are not an endorsement of a particular manufacturer's product. The appendix lists websites that are recommended as a resource for further information.

Assistive technology refers to devices or pieces of equipment that are designed to help achieve or improve function towards greater independence (O'Shea, Carlson, & Ramsey, 2006). Examples of assistive technology include equipment for positioning, mobility, eating, communication, bathing aides, and mechanical lifts. Modification of the physical environment is often necessary for accessibility. Examples of modifications include a ramp for wheelchair access, increasing the width of doorway, and a roll in shower. Accommodations may include an instructional support person to enable a child to participate in the regular education program at school or locating the child's bedroom on the first floor of a house.

Assistive Technology

Assistive technology can offer children with physical disabilities the opportunity to participate more fully and become more independent in their daily lives. Successful use of assistive technology involves a thorough process of needs assessment, selection, implementation, and follow-up. The child and all persons involved in the care of the child should be involved in decision-making.

Assistive technology is sometimes overlooked for young children with disabilities (Long, Huang, Woodbridge, Woolverton, & Minkel, 2003). Lagone, Malone, and Kinsley (1999) provide recommendations for technology to enhance the communication, socialization, and play of young children with disabilities that range from toys that can be made in the home, to commercially available toys with or without modifications, to technical devices like a computer with specialized hardware and software. (See examples at enablingdevices.comasl-inc.com; and ahf-net.com.)

As sistive technology must be monitored for needs that arise as a result of physical growth and changes in the child's physical and social environment. Since most families do not have personal resources to cover the cost of assistive technology, funding is a primary consideration. The following paragraphs describe assistive technology for seating, standing, and mobility.

Seating Systems

Children in levels IV and V have impairments in postural control and musculoskeletal alignment that contribute to activity limitations in sitting. A seating system usually is recommended for optimal positioning. Seating systems are usually attached to a mobility base - together they make up a wheelchair. Seating systems vary from a proper size chair with seat belt to more individualized and complex options involving head, trunk, leg, and arm supports. Children classified in levels IV and V typically require a custom seating system, particularly if there are fixed skeletal deformities.

Components for consideration when customizing a seating system include the headrest, seat and back inserts, anterior and lateral trunk supports, arm supports, and leg supports. (See examples at aelseating.com and bodypoint.com). A seating system that allows change in orientation in space is a consideration for children who are unable to fully control movement of the head and trunk, and have respiratory and/or gastrointestinal problems such as reflux. In our experience, the tilt in space feature and custom molded backs for seating systems minimize skin problems and deformities, and promote comfort and proper alignment. Children who have limitations with weight shift may require special consideration for pressure relief in sitting. Skeletal asymmetries, skin temperature, moisture and shear and compressive forces can contribute to the development of pressure sores (Crenshaw & Vistnes, 1989). There are a variety of cushion materials available to meet the individual requirements for pressure relief including air (rohoinc.com ); gel (sunrisemedical.com/ ), and polyurethane foam (invacare.com ). Yuen & Garrett (2001) compared these three cushion materials in a 19 year-old male with a complete thoracic level spinal cord injury and reported that seating surface pressure was lowest for the air cushion.

Research indicates that upright orientation can improve pulmonary function (Nwaobi & Smith, 1986), oral motor control during eating and drinking (Hulme, Shaver, Acher, Mullette, & Eggert, 1987), and social participation (Hulme, Poor, Schulein, & Pezzino, 1983). Children who spent more time sitting and less time lying down were reported to maintain better alignment in sitting and have more social interaction (Hulme et al., 1983; Hulme et al., 1987).

Variability in children's characteristics and responses suggest that decisions on system components and seating angles should be made on an individual basis. Optimal seat to back angle has been examined by reclining the back (Nwaobi, Brubaker, Cusick, & Sussman, 1983), reducing the seat angle (Nwaobi et al., 1983), increasing the seat angle (Myhr & von Wendt, 1993), and changing orientation of the trunk and head in space by tilting/rotating the entire seating system (Nwaobi et al., 1983). The findings underscore the importance of a team approach and the opportunity to experiment with different options prior to purchasing a seating system. A multi-disciplinary seating clinic and equipment suppliers are valuable community resources.

Adaptive Standing and Walking

Standing has important psychological and physiological implications for child development. Upright orientation improves attention and facilitates social interactions by placing the child at eye level with peers and adults. Studies have documented the value of standing programs in improving bone density. Bone growth is facilitated by weight bearing forces (Chad, Bailey, McKay, Zello, & Synder, 1999). Weight bearing is important for formation of the hip joint (acetabulum) and bone mineralization (Stuberg, 1992; Chad et al., 1999). Children in levels IV and V often have diminished bone density (osteopenia) increasing the risk of bone fracture with minimal trauma (Croarkin, 2001; Henderson et al., 2002).

Standing programs are recommended for children in levels IV and V beginning at 12 to 16 months of age. Stuberg (1992) recommends a standing program of 45-60 minutes 4 to 5 times per week for bone development and 45 minutes 2 to 3 times per day for prevention of contractures of the legs. Gudjonsdottir and Stemmons-Mercer (2002a) reported a case series on four children with cerebral palsy who stood for 30 minutes 5 days per week for 8 weeks. Two children who used a dynamic stander and one child who used a static stander had increased bone mineral density of the distal femur following the standing program. Caulton et al. (2004) examined the effect of duration of standing on bone mineral density using a randomized control trial involving 26 children with cerebral palsy who were unable to walk. Children in the experimental group stood 50% longer and over a 9 month period had a mean increase in vertebral bone mineral density that was 6% greater than children in the comparison group. A key consideration is the amount of body weight the child supports and ability to shift weight. Stuberg (1992) recommended loading of up to 70-75% body weight in a near vertical position.

There are several types of standers: supine, prone, and sit-to-stand. Standers may be static or mobile ( rifton.com ). Supine standers are frequently used with children who have poor head control. Prone standers ( leckey.com ) are used to help improve head control and facilitate weight shift. Two people may be needed to place a child in a prone stander. The sit-to-stand stander ( allegromedical.com/brands/easy-stand.html ) provides supportive transition from sitting to standing. A lifting mechanism allows quick and easy transition from sitting to standing. It can be used as an upright stander and school desk. With a static stander, the child's lower extremities and at least the lower part of the trunk typically are held firmly in position with padded straps (Gudjonsdottir & Stemmons-Mercer, 2002b). A stander may be attached to a wheel base enabling children to be transported short distances while in a standing position. Splints or orthoses are often needed to improve ankle and foot alignment and weight distribution in standing (Stuberg, 1992). During initial prescription, the amount of vertical loading can be checked by placing a scale underneath the child's feet.

An option for children who use power mobility is a modular system that functions as a power wheelchair and is electrically converted to an upright stander or reclined for positioning in supine ( redmanpowerchair.com/pediatrics.php )

Use of a body support walker for standing, mobility, and social interaction warrants consideration for children who lack the trunk and arm control needed to use a conventional hand-support walker. Often referred to as a gait trainer , the trunk, pelvis, and legs are supported by a system (orthosis) that attaches to a wheeled frame to facilitate standing and walking (Snugseat and rifton.com/products/mobility/pacergaittrainers/index.html). Wright, Belbin, Slack, and Jutai (1999) evaluated the effects of one system, the David Hart Walker Orthosis TM ( novita.org.au ) in 20 children, 4 to 13 years of age, with cerebral palsy who were unable to use a conventional walker. The David Hart Walker Orthosis is a modular brace that fits on the child's trunk, pelvis, and legs and has a spring loaded attachment to a wheeled frame. After 12 months of use, children significantly improved their ability to complete a standardized mobility assessment. Six children were reported by their parents to move considerable distances and use the walker for a variety of activities, 6 children were reported to use the walker for short distances at home and school, and 7 children were reported to use the walker primarily for standing and exercise. At home, children used the walkers an average of over 5 hours per week; 15 children were reported to use the walker at least 5 days per week. Eight parents indicated their child's ability to interact with other children increased when using the walker. Overall, the walker met or exceeded the expectations of 13 parents. Parents indicated that difficulty with directional control limited independent use. Lower ratings for satisfaction were given to getting the child in and out of the walker, and portability.

Positioning and Transfers

Children in levels IV and V require adult assistance throughout the day for positioning and movement. Goals and interventions include: a) implementation of a schedule of position changes during daily activities and routines, b) planned opportunities for movement and aerobic exercise, and c) maintenance of respiratory function as a strategy for prevention of acute illness. In order to promote skin integrity, we recommend that the child change position at least every 2 hours. It is important to provide the child with a variety of positioning options. A schedule with pictures of the child demonstrating proper positioning provides both a visual reminder for the child and an instructional tool for care givers. Video tapes are another method of instruction on proper positioning.

The ability to support body weight through the legs and walk short distances with physical assistance of an adult are important outcomes. Performance of a standing transfer with assistance of one person improves the ease of care giver assistance and reduces the risk for care giver injury from lifting. The ability to walk short distances with adult assistance allows for ease in transfers and participation in community activities when wheelchair accessibility is restricted.

The finding from the Ontario Motor Growth Study that 39% of parents of children in level V reported that they carry their child at home (Palisano et al., 2003), reinforces the importance of safety and injury prevention. The physical therapist can assist families through: a) instruction of caregivers in proper lifting and transfer techniques, b) recommendations for environmental modifications, and c) selection of assistive technology such as mechanical lifts and bathing equipment to reduce the physical demands of care giving.

Wheeled Mobility

Wheelchairs consist of a seating system (previously described) and a mobility base. Depending on the child's motor abilities, mobility bases can provide for independent mobility or for being transported by a companion. Transporter chairs, manual wheelchairs, one-arm drive manual wheelchairs, and power chairs are among the options available to fit the individual needs of children and care givers. Children in levels IV and V are usually transported in a wheelchair at school, outdoors, and in the community (Palisano et al., 2003). Self-propulsion of a wheelchair is restricted by impairments in control of trunk and arm movements and lack of endurance.

Transportation safety is a consideration when selecting a wheelchair ( travelsafer.org/resources.shtml ). If the child cannot transfer and cannot use a transport wheelchair, a wheelchair with a metal frame should be used with a wheelchair tie-down and occupant restraint system that meets safety standards. An occupant restraint system is a four point strap system that attaches to the wheelchair frame at four separate points and attaches to the vehicle at four separate anchor points. Attachment points should be as high as possible but below the seat surface. Rear tie-down straps should maintain a 30 to 45 degree angle with the vehicle floor (wc-transportation-safety.umtri.umich.edu/wts-standards).

Power Mobility

Power wheelchairs can provide children a means of independent mobility that enables active participation in daily life (Bottos, Bolcati, Sciuto, Ruggeri, & Feliciangeli, 2001) ( permobil.com ). Children can explore the environment, feel in control, make choices, and learn from mistakes (Deitz, Swinth, & White, 2002; Nilsson & Nyberg, 2003). Children in level IV are good candidates for power mobility. In the Ontario Motor Growth Study, however, only 24% of children in level IV between 4 and 12 years of age used power mobility (Palisano et al., 2003). Personal and environmental factors are important considerations for power mobility. Family and child attitudes, cognitive level, ability to physically activate controls are personal factors. The size of homes, accessibility of home and public buildings, and rough terrain and availability of transportation for powered wheelchairs are environmental factors (Berry, McLaurin, & Sparling, 1996). The time and effort to transport a power wheelchair can restrict use. The cost of a power wheelchair is a potential limiting factor.

Wellness and Prevention of Secondary Complications

Proper nutrition is important for bone growth and mineralization. Children with eating and feeding difficulties are at risk for low intake of calcium and vitamin D. Catabolism of vitamin D is a side effect of anti-epileptic medications. Measurement of bone mineral density by a DEXA [Dual Emission X-ray Absorptiometry] scan is often recommended for children who do not walk. DEXA scan uses x-rays along with a detector and a computer to calculate bone density. A DEXA scan of the spine and/or hip is most often performed. If the results indicate low bone mineral density, medications may be prescribed to help improve the quality of the bone (Henderson, Kairalla, Abbas, & Stevenson, 2004; King, Levin, Schmidt, Oestreich, & Heubi, 2003; Henderson et al., 2002). During adolescence, weight control may become a problem because of poor nutrition and a sedentary life style. The adolescent and care givers should be provided information on proper eating habits, weight management and weight reduction strategies. Consultation with a nutritionist may be helpful.

Children who are limited in the amount and range of active movement are at risk for muscle shortening, joint contracture, and poor skeletal alignment. Several factors are thought to contribute to secondary musculoskeletal impairments and pain in individuals with cerebral palsy: physical growth, inability of muscle to lengthen in proportion to bone growth, excessive biomechanical forces through joints during weight bearing activities, overuse syndromes, immobility, fatigue, obesity, stress/depression, and early joint degeneration (Schwartz, Engel, & Jensen, 1999; Murphy, Molnar, & Lankasky, 1995; Turk, 1994; Cathels & Reddihough, 1993).

Maintenance of muscle length and joint range of motion are necessary for posture and movement and prevention of secondary complications. A guiding principle for intervention is to provide a slow, submaximal stretch for prolonged periods (Palisano et al., 2004). Proper positioning throughout the day, joint immobilizers, serial casts, and orthoses (splints, braces) are procedures used to provide slow, submaximal stretch for prolonged periods. Research supports the use of serial casts to improve joint range of motion (Brouwer, Davidson, & Olney, 2000; Tardieu & Tardieu, 1987). The use of air splints (Kerem, Livanelioglu, & Topeu, 2001) or other types of splints as positioning devices can assist with proper alignment while children are involved in physical, educational or social activities (Palisano et al., 2004). Strategies that we have found effective in maintaining range of motion include the use of night splints, and instructions to the child and caregivers on how to incorporate active movement and passive exercises into daily activities and routines. If the child wears a splint or brace, the fit, skin tolerance and wearing time must be evaluated on a regular basis.

Participation in Physical, Recreational, and Leisure Activities

Social participation is an important outcome for children with physical disabilities. Opportunities for social interactions may be limited. Social and attitudinal barriers can restrict participation in leisure and recreational activities by children who use wheelchairs. Children should be encouraged to develop leisure and recreational interests and participate in community programs like the Scouts or 4-H Club. Sports activities, such as swimming and horseback riding, provide opportunities for fitness and social interaction. Many communities have universally accessible playgrounds that allow children of all abilities to have fun. Accessible playgrounds provide safe play environments where children can interact with each other and play to their highest potential ( righttoplay.org/boundless.htm​ ). For adolescents and young adults, youth groups for persons with disabilities may provide an opportunity for socialization and peer support.

Participation in sports provides learning skills, setting goals, having fun, and being part of a team. We have found sports therapy programs to offer pain free movement and promote physical fitness. A sports therapy program should consider safety, enjoyment, and effectiveness. Aquatics and therapeutic horseback riding ( narha.org ) address specific impairments and enhances functional improvement while sustaining the child's interest and enthusiasm (Sterba, Rogers, France, & Vokes, 2002). The buoyancy of the water makes it easier to participate in fun activities such as games and races as well as fitness programs. Many communities have swimming pools that are accessible to children with disabilities. Aquatics is an activity that the entire family can enjoy together.

In most communities, there is a need for fitness and recreation programs that are available and accessible to children with disabilities. Physical therapists and other health care professionals are encouraged to develop partnerships with community agencies and fitness instructors to develop programs for children with disabilities that are safe and effective. The local recreation center can potentially provide a variety of programs to encourage cardiovascular endurance, strengthening, and flexibility programs. A pulmonary hygiene program to promote a productive cough may be incorporated into an exercise and fitness program.

Summary

The ultimate goals of therapy interventions are to support families and enhance the quality of children's participation in home, school, and community life. Children with cerebral palsy who require adult assistance for mobility and self-care can benefit from assistive technology, environmental modification and accommodation to maximize adaptive gross motor function. Weight support through the legs, frequent changes in positioning, and opportunities for social participation are important for wellness and prevention of secondary complications. In addition, assistive technology, modifications, and accommodations can increase the ease of care giving, an important outcome for many families. Therapists are encouraged to collaborate with children and their families when making recommendations on assistive technology, environmental modifications, and accommodations. Therapists also can educate children and their families about health promotion including prevention of secondary musculoskeletal impairments and consult to educational and community personnel on participation in recreation and sports activities.

Appendix: Recommended Web-sites

MOVE (Mobility Opportunities Via Education) is dedicated to helping children and adults with severe disabilities sit, stand, and walk. They provide instruction and adaptive equipment that enhances independent mobility. Training is provided to families, care providers, and professionals.

The National Center on Physical Activity and Disability (US) is an information center concerned with physical activity and disability. They provide information, options, assistance and resources from guidelines to fact sheets on many activities, games, recreational pursuits, and sports that have been adapted for participation of people with disabilities.

The National Center on Birth Defects and Developmental Disabilities provides information pertaining to cerebral palsy, and resources available to improve the quality of care of these children and enhance the potential for full productive living. They provide links to other web sites to learn more about the topics.

Tobii Dynavox delivers a broad range of augmentative and alternative communication tools. They offer a wide range of software and hardware technology and extensive customer support program.

The professional association for the advancement of rehabilitation and assistive technology. It promotes research, development, education, advocacy and provision of technology.

This US federally funded project provides information on assistive technology and rehabilitation equipment available from domestic and international sources to consumers, professionals and caregivers. Includes a database that contains information on more that 30,000 assistive technology products, contains description of product, price, and company information.

National Osteoporosis Foundation (US) provides information and resources for the prevention, early detection and treatment of osteoporosis.

Triad is a manufacturer and supplier of children's rehabilitation products. They focus on foot pedal and hand crank tricycles, gait trainers, and toileting/shower chairs.

NICHCY is one of four clearinghouses established by Congress to provide specialized information on disabilities.

This site offers pediatric equipment from a variety of manufactures.

This online catalog has a pediatric section with categories including toileting and bathing; mobility; bikes and helmets; and standers.

Guidelines for safely transporting wheelchair users.

Provides child passenger safety information.

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