Physical education for children with Prader-Willi syndrome.

Robert C. Weber is assistant professor of physical education at Texas Tech University. He is also coordinator of Adapted Physical Education Programs and sponsor for the wheelchair athletic club. In addition, he has been active with Special Olympics.

According to Public Law 94-142 (1975) all handicapped children are entitled to a free public education that meets their individual and unique needs, including physical education. Benefits of physical education for children with disabilities are widely documented in the literature (Cratty, 1989; Dunn & Fait, 1989; French & Jansma, 1982; Kalakian & Eichstaedt, 1982; Seaman & DePauw, 1989; Sherrill, 1986). Children with Prader-Willi syndrome have a need and can benefit from participating in physical exercise and leisure activity programs (Page, Stanley, Richman, Deal, & Iwata, 1983). Due to obesity and behavioral problems, children with Prader-Willi syndrome may seem disinterested in participating in physical education. Because of this apparent disinterest in physical activity and need for increased physical activity to control their weight, it is very important that these children have positive experiences in physical activities with friends, family members, and in various school programs. From results of recent studies, children with Prader-Willi syndrome can benefit from instruction in physical education and learn to enjoy physical activity (Weber & Miller, 1990; Weber, Bobo, Wolfe, & Robert, 1990).

During the past several years, the author has had the opportunity to work directly with several children with Prader-Willi syndrome. Due to a previous lack of research findings and information involving instructional methods for these children in physical education, the author has become actively involved with colleagues in research studies involving various physical fitness parameters and biomechanical analyses of gross motor skill performances of these individuals (Weber & Miller, 1990; Weber et. al., 1990). From these studies some key ideas have been developed that can be helpful to physical educators who teach students with Prader-Willi syndrome. To provide meaningful physical education experiences, physical educators should be knowledgeable about etiology, characteristics, teaching considerations, and suggested activities for the child with Prader-Willi syndrome.

Etiology

In 1956, Prader, Labhart, and Willi described a new syndrome which has characteristics of obesity, short growth, poor development of genitalia, and mental retardation, with deficiency in muscle tone in the neonatal period (Juul & Dupont, 1967). Since then what is commonly referred to as Prader-Willi syndrome has been reported in the literature under various titles such as Syndrome of Willi Prader (Royer, 1963); of Willi, Prader, and Labhart (Larbre, 1965); of Prader, Labhart, and Willi (Dunn, 1968); of Prader, Labhart, Willi, and Fanconi (Hooft, Delire, & Casneuf, 1966); and HHHO (Zellweger & Schneider, 1968).

This condition is considered to be very rare with Crnic, Sulzbacher, Snow, & Holm (1980) estimating an incidence of between 1 in 5,000 and 1 in 10,000 births. Cause of the syndrome has been traced to an abnormality, resulting in a deletion of chromosome 15 contributed by the father (Bonuccelli, Stette, Levitt, Levin, & Pyeritz, 1982; Butler & Palmer, 1983; Elder, Nichols, Hood, & Harrison, 1985; Fear, Mutton, Berry, Heckmatt, & Dubowitz, 1985; Kousseff, 1980; Ledbetter, Riccardi, Airhart, Strobel, Keenan, & Crawford, 1981; Ledbetter, Mascarello, Riccardi, Harper, Airhart & Strobel, 1982).

Characteristics

Prader-Will syndrome is characterized during infancy by hypotonia, weak cry, poor sucking, and failure to thrive (Berry, Whittingham & Neville, 1981; Brissenden & Levy, 1973). These infants are considered behaviorally and psychomotorically to be retarded, especially in regard to developmental milestones of ability to hold the head erect, sitting, walking, and talking (Foster, 1971; France, Beemer, & Ippel, 1984). Obesity generally becomes prominent between one and four years of age, with face, lower trunk, and buttocks more involved than the rest of the body (Cline, Williams, & Smith, 1970; Foster, 1984).

During childhood, the syndrome is characterized by abnormal increase in appetite, obesity, short stature, small hands and feet, malformed facial features, mental retardation, and motor delays (Crnic et. al., 1980; Zellweger & Schneider, 1968). Other symptoms can include hypogonadism, central nervous dysfunction, scoliosis, abnormalities of the central visual pathways, and diabetes(Bray, Dahms, Swerdloff, Fiser, Atkinson,& Carrel, 1983; Creel, Bendel, Wiesner, Wirtschafter, Arthur, & King, 1986; Hamilton, Scully, & Kliman, 1972; Hittner, King, Riccardi, Ledbetter, Borda, Ferrell, & Kretzer, 1982; Holm & Laurnen, 1981; Magana, 1984; Tamarkin, Abastillas, Chen, McNemar, & Sidbury, 1982).

According to Holm and Pipes (1976) and Otto, Sulzbacher, and Worthington-Roberts (1982), food-related behavior problems are common. Individuals with Prader-Willi syndrome have been known to steal and eat products such as dog food which typically are considered unappetizing (Holms, Moser, Halldorsson, Mack, Pont, & Matzilevich, 1972). Excessive appetitie exhibited by children with Prader-Willi syndrome is thought to be biologically based and results from a hypothalamic disturbance which leads to obesity (Hall & Smith, 1972; Zellweger & Schneider, 1968).

Families of students with whom the author has worked have been forced to place locks on refrigerators, freezers, and kitchen cabinets. In addition, family members, teachers, and others working with or associated with these individuals must monitor and alter eating patterns.

Several studies have attempted to control obesity in children with Prader-Willi syndrome through dietary management with limited success (Bistrian, Blackburn, & Stanbury, 1977; Coplin, Hine, & Gormica, 1976; Page, et al., 1983; Pipes & Holm, 1973; Wodarski, 1985). This is particularly difficult according to Holm and Pipes (1976) since caloric requirements for weight maintenance in requirements for weight maintenance in Prader-Willi syndrome have been found to be 20-50% lower than in normal-weight individuals. Surgical procedures such as small intestine bypass (Bristrian et. al., 1977) and gastric bypass (Soper, Mason, Printer, & Zellweger, 1975) have been successful but are not recommended due to possible complications with dehydration, malnutrition, and liver damage.

After 15 years of age, individuals with Prader-Willi syndrome usually are very obese, have defiant scoliosis, and heart problems. Due to heart problems, which usually result in cardiorespiratory failure, average age expectancy for these individuals is the late twenties. The oldest known individual having Prader-Willi syndrome lived to 42 years of age (Zellweger & Schneider, 1968). In addition, these individuals are also sexually underdeveloped and exhibit behavioral problems characterized by stubbornness and sudden outbursts of temper (Laurance, Brito, & Wilkinson, 1981).

Teaching Considerations and Techniques

The following teaching considerations, as well as techniques, are results of personal research completed and medical considerations. Children with Prader-Willi syndrome have so many different medical considerations that usually an individualized education plan taught by an adapted physical education specialist is needed. From past experiences of the author, the earlier the adapted physical educator and various other members of the motor development team, such as a physical therapist, can begin working with these children the better. Fortunately with passage of PL 99-457 (1986), this intervention can begin shortly after birth once Prader-Willi syndrome is diagnosed.

The adapted physical education specialist must collect as much information as possible about the student. Sources of information should include classroom teachers, aides, psychologists, parents, siblings, medical personnel, and others who have worked with the child. This sharing of pertinent information among physical educator, classroom teacher, and parents needs to be done daily so that food intake, medication, and behavior management can be monitored. In addition, it is important for the physical eductor to become well acquainted with the child so that a mutual trust and understanding can develop. This allows the physical educator to understand the child and to motivate him to participate in regular physical activity.

The teacher should assess abilities of each child on a regular basis and utilize teaching techniques that encourage the child to improve weaknesses. At the same time the child needs to use learning strengths with the teacher making necessary modifications and manually assisting if needed. Accurate records for each child on participation, skill acquisition, and behavioral management techniques utilized are important for monitoring progress and programs.

Dealing With Hypotonisity

Since these children at an early age are considered hypotonic (Berry, Whittengham, & Neville, 1981; Brissenden & Levy, 1973), and have early signs of motor delay (Stephenson, 1980), a program which encourages physical activity and motor patterning of various muscle groups is very important. Problems of hypotonisity and motor delay appear to be caused by ultrastructured abnormalities of the thick filaments of the sarcomere and increased osmiophilic density of Z lines (Afifi, 1969; Afifi & Zellweger, 1969). According to Afifi and Zellweger (1969), with muscle stimulation and patterning the hypotonic conditions of individuals with Prader-Willi syndrome at birth can be improved with age. Examples of early intervention techniques that have been successful involve sensory stimulation, positioning and placement strategies, rhythmic sterotypes, utilization of objects to motivate actions, and good therapy hands (manual assistance) which have been recommended for hypotonic children by Cratty (1989).

Dealing with Obesity

According to Holm and Laurnen (1981), obesity generally becomes prominent at about two or three years of age, so parents and members of the motor team need to get these children into early patterns and routines of vigorous daily exercise. This is especially important in light of well documented food-related behavior problems and biological need for fewer calories (Holm & Pipes, 1976). Because of need for fewer calories, strict observation of calorie intake in conjunction with a minimum of two hours of vigorous daily activity are recommended (Weber et al., 1990). From observations made by the author and research by Weber et al. (1990), activities that can be engaged in on a regular basis with family members and/or peers tend to be most successful.

The extent of obesity that develops in these individuals is important because of other possible medical and mental considerations. Holm and Lauren (1981) reported that the more obese individuals with Prader-Willi syndrome become, the more prevalent and severe scoliosis becomes. Tamarkin et al. (1982) also reported that incidence and severity of diabetes increases with obesity.

However, one of the most interesting studies was that of Crnic et. al. (1980) regarding degree of obesity and intelligence. In this study it was reported that early intervention prevented obesity in one group of children with Prader-Willi syndrome, and that this group had significantly higher intelligence test scores than two other groups which did not have regular physical activity from an early age. These findings suggested that early factors of brain development (possibly related to myelination, neurodevelopment factors, and negative psychosocial factors) determine subsequent IQ in this syndrome.

Dealing with Mental Retardation

Individuals with Prader-Willi syndrome are mentally retarded, but degree of retardation varies. The adapted physical education specialist must be aware of degree of retardation of each student since this affects instructional techniques. Some teaching suggestions for individuals with mental retardation presented by Seaman and DePauw (1989) that have been found to be pertinent in trial and error experiences of the author with children possessing this syndrome include--

* Simplify and sequence instruction using short simple sentences.

* Praise attempt and reinforce performance with social praise (do not use food).

* Include structure and routine while stressing safety in the program.

* Use tactile and kinesthetic cues and physical shaping if necessary.

* Provide opportunity for increasing emotional adaptability by systematically and slowly changing structure.

* Use demonstrations by teachers, aides, and other students.

While teaching new tasks, utilization of task variation with interspersed maintenance tasks has been highly successful. Examples of how to utilize the task variation teaching method with special populations in physical education are given by Weber (1987). Reduced student-teacher ratios are required to work effectively with these children due to the combination of physical, mental, and behavioral problems, so as to meet individual and unique needs.

Dealing with Visual Problems

Many different visual impairments have been associated with Prader-Willi syndrome, including convergent strabismus, glaucoma, nystagmus, cataracts, and ocular albinism (Creel et. al., 1986; Futtenweit, Ritch, Teckhasaenee, & Nelson, 1986; Hittner et. al., 1982; Vukcevich, Adler, Hornblass, & Gombos, 1979).

According to Hittner et. al (1982), oculocutaneous albinoidism (absence of pigmentation in eyes, skin, and hair) is a component of the chromosome 15 deletion which causes Prader-Willi syndrome. Because of this condition these individuals are wear sunglasses for most activities. In addition, Creel et al. (1986) indicated that individuals with Prader-Willi syndrome have misrouting of optic fibers which can result in strabismus and nystagmus. Either one of these conditions could adversely affect throwing, catching, and any other eye-hand or eye-foot coordination skills. The development of cataracts has also been associated with these individuals who have diabetes.

Dealing with Other Physical Factors

Individuals with Prader-Willi syndrome are reported to have small feet and hands and be significantly shorter than peers (Butler & Meaney, 1985; Cline et. al., 1970). Differences observed in hand size and structure of middle and distal phalanges of the fifth finger have been suggested as possible diagnostic tools for physicians suspecting this syndrome (Butler, Kaler, Yu, & Meaney, 1982). Because the hands are so small compared to the average mainstreamed student, throwing and catching skills appear to be adversely affected (Weber & Miller, 1990). Since the feet are also small, it has been the experience of the author that balance in some activities is affected. This appears to be a problem not only because of small size of the feet, but because these children tend to be 3 standard deviations below average peers for height and 3 standard deviations above average peers for weight (Cline et. al., 1970). Combination of excessive weight on a short frame and small feet causes balance problems, especially during locomotion. These individuals, according to the research of Weber and Miller (1990) and photographs in various reports, are knock-kneed, which may also affect dynamic and static balance.

Since cardiorespiratory problems are common in older individuals with Prader-Willi syndrome, activities such as swimming, jogging, biking, rowing, canoeing, and cross-country skiing are excellent with moderation. However, it is advisable that teacher and/or student closely monitor heart rate of the student and duration of activity. Until the student has built up endurance over a period of time, frequent rest periods may be needed. In addition, according to Bye, Vines, and Fronzek (1983), obesity hyperventilation syndrome may be present, which the physical educator must keep in mind.

Use of Behavior Modification 

One major teaching consideration when working with individuals possessing Prader-Willi syndrome is use of various behavior modification programs. Because of tendency toward obesity, food and drinks commonly used in special education as rewards for good behavior are contraindicated. In the physical education setting, as well as time between classes, food scavenging can be a problem. It is important that all school personnel closely observe these individuals and not allow them to eat food except at scheduled meals. In addition, excessive mood and behavior changes are quite common. Individuals with Prader-Willi syndrome older than 4 years of age are noted for excessive stubborness and negativism leading at times to violent outbursts of rage (Zellweger & Schneider, 1968). Based on past experiences, a combination of social reinforcement and token economy incentives work well to control and change behaviors.

As the student enters junior and senior high where showering is often expected, additional problems due to poor development of genitalia and secondary sex characteristics occur in individuals with Prader-Willi syndrome. This problem usually occurs because of taunting by other students, if the physical educator does not intervene to keep other students from teasing the individual (Hamilton et. al., 1972; Magana, 1984; Zellweger & Schneider, 1968).

Suggested Activities Physical and Motor Fitness

Like most youngsters, children with Prader-Willi syndrome need and can benefit from activities involving muscular strength, muscular endurance, flexibility, cardiovascular endurance, balance, agility, speed, coordination, and reaction time. These skills can be developed through a number of lead-up games and activities ranging from playing tag and parachute activities to weight training. Most physical and motor fitness activities utilized with mainstreamed children are appropriate; however, children with Prader-Willi syndrome, based on research of Weber et. al. (1990), may need to have more exercise compared to mainstreamed students due to physical and motor fitness problems. to physical and motor fitness problems.

Fundamental Motor Skills and Patterns

Since children with Prader-Willi syndrome have below average motor skills (Afifi & Zellweger, 1969; Stephenson, 1980; Zellweger & Schneider, 1968), it is important they be taught fundamental motor skills such as running, jumping, throwing, catching, sliding, hopping, galloping, skipping, and striking. These skills are important because they are building blocks for more advanced skills and games. Activities such as jogging, biking, and dancing are excellent weight control activities that can be enjoyed with family members and peers in leisure time activities.

In addition, the author has effectively utilized the Portage Guide to Early Education Curriculum (1975) and the I CAN program (Wessel, 1976) with these individuals.

Skills in Aquatics, Dance, Individual and Group Games, and Sports

Individual sports which children with Prader-Willi syndrome seem to enjoy include bowling, roller and ice skating, snow and water skiing, rowing, canoeing, swimming, and dancing. Most of these activities are excellent for cardiorespiratory endurance and weight control. These activities also have high priority because they are lifetime activities the whole family can enjoy. The I CAN program (Wessel, 1976) and Special Olympic Sports Skills Instructional Program have both been successfully utilized by the author.

Conclusions

The author has been successful, based on results of the study by Weber et al. (1990) and improvement on test results for the AAHPERD Fitness Test, in programming physical education activities for children with Prader-Willi syndrome. This has especially been true when a concentration of activities has been on basic skills, weight control, and lifetime activities. To be successful, however, it is important to intervene early, control weight through diet and exercise, and involve family, as well as friends of the student in regular cardiorespiratory endurance activities.

Those wishing general information regarding Prader-Willi syndrome are encouraged to write: Prader-Willi Syndrome Parents and Friends, Box 252, Long Lake, Minnesota 55356.

Selected References

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Afifi, A.K. and Zellweger, H. (1969). Pathology of muscular hypotonia in the Prader-Willi syndrome light and electron microscopic study. Journal of the Neurological Sciences, 9, 49-61.

Berry, A.C., Whittengham, A.J., & Neville, B.G. (1981). Chromosome 15 in floppy infants. Archives Disabled Children, 56 (11), 882-885.

Bistrian, B.R., Blackburn, G.L., & Stanbury, J.B. (1977). Metabolic aspects of a protein-sparing modified fast in the dietary management of Prader-Willi obesity. The New England Journal of Medicine, 296, 774-779.

Bonuccelli, C.M., Stetten, G., Levitt, R.C., Levin, L.S., & Pyeritz, R.E. (1982). Prader-Willi syndrome associated with an interstitial deletion of chromosome 15. The Johns Hopkins Medical Journal, 15, (5), 237-241.

Bray, G.A., Dahms, W.T., Swerdloff, R.H., Fisher, R.H., Atkinson, R.L., & Carrel, R.E. (1983). The Prader-Willi syndrome: A study of 40 patients and a review of the literature. Medicine (Baltimore), 62(2), 59-80.

Brissenden, J.E., & Levy, E.P. (1973). Prader-Willi syndrome in infant monozygotic twins. American Journal for Disabled Children, 126, 110-112.

Butler, M.G., Kaler, S.G., Yu, P.L., & Meaney, F.J. (1982). Metacarpophalangel pattern profile analysis in Prader-Willi syndrome. Clinical Genetics, 22, 315-320.

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Butler, M.G., & Palmer, C.G. (1983). Parental origin of chromosome 15 deletion in Prader-Willi syndrome. Lancet, 1, 1285-1286.

Bye, A.M., Vines, R., & Fronzek, K. (1983). The obesity hypoventilation syndrome and the Prader-Willi syndrome. Australian Pediatric Journal, 19, 251-255.

Cline, M.J., Williams, H.E., & Smith, L.H. (1970). The Prader-Willi syndrome. California Medicine, 112 (1), 65-73.

Coplin, S.S., Hine, J., & Gormican, A. (1976). Outpatient dietary management in the Prader-Willi syndrome. Journal of the American Dietetic Association, 68, 330-334.

Cratty, B.J. (1989). Adapted physical education in the mainstream (2nd edition). Denver, CO: Love Publishing Company.

Creel, D.J., Bendel, C.M., Wiesner, G.L., Wirtschafter, J.D., Arthur, D.C., & King, R.A. (1986). Abnormalities of the central visual pathways in Prader-Willi syndrome associated with hypopigmentation. The New England Journal of Medicine, 314, 1606-1609.

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Holmes, L.B., Moser, H.W., Hallorsson, S., Mack, C., Pont, S.S., & Matzilevich, B. (1972). Mental retardation: An atlas of diseases with associated physical abnormalities. New York: McMillan.

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Holm, V., & Pipes, P. (1976). Food and children with Prader-Willi syndrome. American Journal for Disabled Children, 130, 1062-1063.

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Kalakian, L.H., & Eichstaedt, C.B. (1982). Developmental/adapted physical education: Making ability count. Minneapolis, MN: Burgess Publishing Company.

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Ledbetter, D.H., Riccardi, V.M., Airhart, S.D., Strobel, R.J., Keenan, B.S., & Crawford, J.D. (1981). Deletions of chromosome 15 as a cause of the Prader-Willi syndrome. The New England Journal of Medicine, 304, 325-329.

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Stephenson, J.B. (1980). Prader-Willi syndrome: Neonatal presentation and later development. Developmental Medicine Child Neurology, 22, 792-799.

Tamarkin, L., Abastillas, P., Chen, H.C., McNemar, A., & Sidbury, J.B. (1982). The daily profile of plasma melatonin in obese and Prader-Willi syndrome children. Journal of Clinical Endocrinology and Metabolism, 55 (3), 491-495.

Vukcevick, W.M., Adler, R.I., Hornblass, R.H., & Gombos, G.M. (1979). Cataracts with obesity, small stature, oligophrenia, and acromicria (Prader-Labhart-Willi syndrome). American Journal of Ophthalmology, 75 (2), 259-260.

Weber, R.C. (1989). Utilizing task variation in adapted PE to motivate and teach disabled students. Journal of Physical Education, Recreation and Dance, 60 (2), 85-87.

Weber, R.C., & Miller, M. (1990). Biomechanic study of six gross motor skills in a Prader-Willi boy. Unpublished manuscript.

Weber, R.C., Bobo, M., Wolfe, D., & Robert, J.J. (1990). Effects of an eight-week physical activity program on the functional capacity of a subject with Prader-Willi syndrome. Unpublished manuscript.

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Acknowledgements--The author would like to thank Dr. Maryln Miller for her assistance in the biomechanic research studies, Drs. Mike Bobo, Roy Wolfe, and Jacalyn Robert for their assistance in the exercise physiology study recently completed, and the families of all the children who have allowed their sons or daughters to participate.