Journal of the American College of Nutrition, Vol. 18, No. 4, 316-323 (1999)
Published by the American College of Nutrition
Body Composition of Children with Myelomeningocele, Determined by 40K, Urinary Creatinine and Anthropometric Measures
Catherine B. Grogan, MEd, RD and
Shirley M. Ekvall, PhD, RD, LD, CNS, FACN
Nutrition Consultant, Fort Lauderdale, Florida, Former Nutrition Trainee/Fellow, University Affiliated Cincinnati Center for Developmental Disorders (UACCDD), Children’s Hospital Medical Center (C.B.G.), Ohio
Chief of Nutrition, University Affiliated Cincinnati Center for Developmental Disorders, Children’s Hospital Medical Center and Professor, Department of Health Sciences, College of Allied Health Sciences, Medical Campus, University of Cincinnati (S.M.E.), Ohio
Address reprint requests to: Shirley M. Ekvall, Ph.D., Nutrition Department, UACCDD, Pavilion Building, Children’s Hospital Medical Center, 3333 Burnet Avenue, Cincinnati, OH 45229
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ABSTRACT
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Objective: The purpose of this study was to develop a method to prevent obesity in myelomeningocele (MM) children by determining the effects of growth, calories and physical activity on body composition and to apply this data to clinical practice, specifically, to correlate lean body mass (LBM) with calorie needs and to correlate body fatness with anthropometry measures.
Methods: The body compositions of 14 children (four males and ten females) with MM were estimated from potassium content (40K), urinary creatinine and anthropometry measurements at the beginning and end of a six-month period. Three subjects who did not have MM were also evaluated as controls. Dietary and physical activity and dietary-goals estimates were taken from records kept by the patients after initial discussion of physical activity and dietary goals with the families.
Results: The study showed potassium content (40K), or LBM, in children with MM to be approximately 50% of the potassium content (40K) of children without MM. The percentage of LBM correlated with physical activity, but not with the location of neurological lesion. Lean body mass and creatinine excretion also were significantly correlated, indicating that creatinine excretion is a good measure of lean body tissue in these children. Thorax and abdominal skinfolds, as well as total circumferential measurements (waist being highest), showed significant correlations with the percent of body fat. The caloric intake requirement to maintain the growth of a child with MM was found to be approximately 50% of the recommended daily allowance (RDA) for a child without MM of the same age. Changes in LBM were observed in children with MM who increased physical activity over a six-month interval and were greater than in those who reduced calories alone, however not significantly, presumably due to the short duration of the study.
Conclusion: To prevent obesity, physical activity should begin in infancy; this will increase LBM and thereby calorie needs. Skinfolds and circumferences (abdominal and thorax skinfolds and waist circumference) which significantly correlated with body fat should be used clinically. Calorie needs according to LBM should be reduced to 50% of the RDA or approximately nine cal/cm height for maintenance or seven cal/cm height for weight loss in MM children after age six (possibly at three to four years of age if nonambulatory).
Key words: body potassium (40K), creatinine excretion, anthropometric measures, myelomeningocele, lean body mass
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INTRODUCTION
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In myelomeningocele (MM), the portion of the body above the neurological lesion is normal in strength, dexterity and skin sensitivity. With proper training, the upper body can compensate for paralysis in the lower extremities. Thus the body composition is different in the upper and lower body. Body composition can play an important role in the functional ability of children with MM.
Gender differences have been noted in body composition in normal children in the general population [1]. However, Pariskova found few gender and age differences in body composition in obese children using body density and skinfold thickness [2]. The amount of potassium in patients with primary muscle disease correlated in large measure with the severity of the muscle involvement [3]. It is believed that the amount of muscle mass in a child with MM is lower than normal, due to the complete or partial denervation of muscles below the neurological lesion; such denervation results in decreased physical activity and subsequent weight gain [4]. The metabolic response to prolonged or severe illness, regardless of the etiology, is the tendency toward progressive loss of body potassium content [3]. The child with MM and associated biological stresses during the growth years may show a decreased potassium content. Total body potassium, and lean body mass, were reported to be proportional to basal heat production in adults [5]. Utilizing the whole body counter to measure lean body mass can be valuable in establishing weight loss goals and in preventing loss of lean body tissue. In another test, urinary creatinine was significantly correlated (r=0.988) with lean body mass using consecutive three-day urinary collections [6].
Roberts et al. reported that in MM after the age of four years, body cell mass and lean mass tissue become increasingly replaced by adipose tissue [7]. In MM the percentage of body fat was significantly greater in those with high-lesions and mid-lesions, and in those in the non-ambulatory group. The percent body fat correlated best with four skinfold measurements, including biceps, triceps, subscapular and suprailiac [7]. Shurtleff et al. [8] concluded that body fat composes a greater proportion of body mass in subjects with MM than in control subjects and that excess adipose tissue bears a statistical relationship to the degree of mobility and the lesion level.
Bandini et al. [9] measured 16 adolescent subjects with MM by indirect calorimetry and the doubly labeled water method. Fat-free mass (FFM) or lean body mass (LBM) was lower in the males and females with MM than in the normal population, but only statistically significantly lower in the females. Bandini et al. [9] measured the total energy expenditure (TEE) and resting metabolic rate (RMR) of ten of the same adolescent subjects and found the calorie needs for nonambulatory subjects significantly reduced. Later the TEE for a younger child with MM (a ten-year-old female) was measured at only 895 kcal needs/day. The indication is that energy requirements in young children with MM are significantly lower than those in normal children. Obesity can cause additional problems in the child with MM, including physical and psychological morbidity, ambulatory deterioration, transference difficulties, a higher incidence of pressure sores, difficulty with hygiene and stomal care, and more complicated surgery [10]. Successful intervention requires parental awareness of the reduced energy requirements. Dietary habits and caloric intakes should be evaluated in children with MM whose weight exceeds the 25th percentile for age [11]. Nutrition interventions should be provided as needed.
Is the obesity commonly seen in children with MM the result of decreased energy requirements, or is low energy expenditure most likely due to reduced ambulation, or both? The whole body counter, anthropometric measurements and creatinine determinations were used as the determinants of body composition in MM children. Thereafter the investigators in turn determined if calories, physical activity or growth had the greatest effect in reducing adipose tissue and maintaining lean body mass over a six-month period. From this information specific anthropometric indices were determined to clinically assess body fatness more accurately in children with MM.
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SUBJECTS AND METHODS
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Four males and ten females ranging from six to 16 years participated in the study. Ten subjects were above the 75th percentile in weight. Three control subjects without myelomeningocele were evaluated, making a total of 17 subjects. Lean body mass of the subjects was determined at University of Cincinnati Medical Center by a specially trained technician using the whole body counter method of Forbes [12]. Subjects were freshly bathed to avoid contamination and wore a light cotton gown. Subjects were placed in a vault room and viewed by an 8x4 inch sodium iodide crystal placed so as to minimize geometric effects. Impulses from the scintillation crystal were fed to a multichannel analyzer where they were sorted into energy groups. A standard curve employing a sugar box phantom with 40K vials was used for the 40K calibration. After suitable calibration, the activity in the 40K photopeak was used to determine the naturally occurring 40K counted in the individual subject during a 30-minute period. Chemical potassium was then calculated. The data generated was processed by computer.
In Period I the subjects were instructed to collect the total urine output for six hours prior to the visit due to frequent diaper usage at all ages. Samples for volume were measured and aliquots in triplicate were frozen until assay. The method of Bonsnes and Taussky [13] was used for creatinine determination. The subjects were weighed in a wheelchair at the hospital, and the actual weight of the subjects was determined from the difference between the total weight and the weight of the wheelchair. Pounds were converted into kilograms. Recumbent heights were taken using a recumbent head board [4]. Skinfold measurements of the subject were taken at several sites using a Lange Caliper with a caliper pressure of about 10 g/mm2 with a contact surface from 20–40 mm2. Linear or circumferential measurements were taken at weight sites with a Lufkin Linen Metric Tape. Location of sites followed the pattern of Steinkamp [14]. Measurements were taken only by the first author (supervised by the second author). Both authors were trained by Alex Roche, M.D., and Cameron Chumlea, Ph.D., from the Fels Growth Research Institute in Yellow Springs, Ohio. A scale for visual observation of fat deposits was developed to determine if a trained observer could ascertain the extent of fat deposits in the child with MM (Table 1). Pictures of the subjects were taken with a Polaroid camera. One copy was given to the subject as a behavior modification tool, and the other was retained by the investigator.
Subjects or caretakers were asked to record personal food intake and physical activity output for four days beginning with the day of the measurements. All recorded data was returned to the clinic upon completion. After evaluation of the four-day diaries, dietary modifications (including 15 minutes of sunshine per day for vitamin D intake), physical activity recommendations and weight goal projections were discussed with and given to the subjects and the parents. An instructional packet of menus, exchange lists and a physical activity expenditure table were given to subjects who were overweight. Subjects were encouraged to increase physical activity. A scale for the evaluation of physical activity is shown in Table 1. The clinic orthopedist and physical therapist were contacted and asked to reinforce the physical activity suggestions.
The procedure used in Period 1 (including 40K measurement) was repeated six months following the initial 40K measurement (Period 2).
The mean and standard deviations were determined for the following parameters, measured in both Period 1 and Period 2: age, weight, height, skinfold thickness, circumferential measurements, potassium, lean body mass, percentage of lean body mass, fat weight, percentage of fat weight, total daily kilocalories, percentage of kilocalories based on recommended daily allowances, total daily protein, percentage of protein based on RDA requirements, physical activity, creatinine excretion per 24 hours, creatinine coefficients, creatinine per centimeter of height, potassium per centimeter of height and visual observation of obesity. Partial linear correlation coefficients were determined for the differences from Period 1 to Period 2 on the linear association between percentage of lean body mass and percentage of calories, physical activity, and growth as measured by height.
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RESULTS
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Partial correlation coefficients were calculated to determine the effect of calories, physical activity and growth on the percentage of lean body mass of 14 patients after the six-month interval. Males and females were combined for statistical analysis since fewer gender differences were found in obese children. Since no parameter measured or calculated between Periods 1 and 2 changed or differed significantly except for vitamin D (Tables 2, 3 and 4), correlation coefficients were determined from Period I (Table 5). Physical activity had the highest partial correlation coefficient with a change in percentage of LBM (0.318) from Period 1 to Period 2. The partial correlation coefficient between LBM and calories was -0.114 and between LBM and change due to growth only -0.029.
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TABLE 3. Measurements—Period 1 and Period 2 (Dietary, Physical Activity, Urinary Creatinine and Visual Observation)
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TABLE 4. Percentage Values of Nutrient Intake of Myelomeningocele Subjects Based on Recommended Daily Allowancesa—Period 1 & 2
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40K Content
The potassium content of a child with MM is about 50% less than that of obese children without MM of similar age according to data from the literature (Table 6). The linear correlation between potassium content and creatinine excretion was significant (r=0.866), indicating that potassium content and creatinine excretion are good indicators of total muscle mass (Table 5). Potassium content and potassium per centimeter of height (r=0.711) correlated highly. Both potassium content and potassium per centimeter of height correlated significantly with creatinine per centimeter of height, r=0.807 and r=0.841, respectively, Table 5.
The percent of LBM or lean body weight of the subjects showed a significant correlation (r=0.840) with the physical activity or exercise of the subjects (Table 5). The children achieving the greatest degree of independence and self-care had the largest amount of LBM. The percentage of LBM and the creatinine per kilogram weight were also significantly correlated (r=0.910).
Creatinine Excretion
Creatinine excretion and potassium content and potassium per centimeter of height had a significant correlation coefficient of r=0.866 (Table 2). Comparison of creatinine excretion and creatinine coefficients (mg creatinine divided by weight in kg) of subjects with MM with those of children who are obese and of similar age are shown in Table 7. Creatinine was not significantly correlated with age in children with MM, in contrast to children in the general population without MM.
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TABLE 7. Comparison of Creatinine Excretion and Creatinine Coefficients of Myelomeningocele Children with Healthy Obese and Normal Weight Children
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Since the LBM and creatinine coefficients were significantly correlated (r=0.910) in the MM subjects, the creatinine coefficient is an indicator of the relative amount of muscle mass (Table 5). The creatinine coefficient and visual observation as well as percent fat had a negative correlation of r=-0.809. The creatinine coefficients of children who were obese with MM ranged from 6.06 to 10.39, indicating lower figures than Talbot’s figures [15].
Children with MM who by visual examination appeared to have normal fat deposits (Table 1) compared similarly in percent of fat to children of normal weight in creatinine excretion and creatinine per kilogram of body weight.
Anthropometric Measurements
Percent of body fat, fat weight, percent of LBM, visual observations and height all correlated significantly with the total skinfolds (r=0.777, r=0.861, r=0.733, r=0.822 and r=0.788, respectively). The correlation coefficients of individual skinfolds and circumferences with body fat are listed in Table 5. The thorax (r=0.810) and abdomen (r=0.807) skinfolds were significantly correlated with percentage of fat (p
0.05), while triceps skinfold (r=0.695) and the waist (r=0.698) circumference were correlated with percentage of fat (p0.10). The subscapular skinfold and percentage of fat were poorly correlated (r=0.154). Individual skinfold correlations were more significant than individual circumferential correlations; however, circumferential measures and weight had the highest correlation (r=0.852) in all cases except in weight and percent of fat. Weight and age also were significantly correlated (r=0.763). Total skinfolds and circumferences only changed slightly from Period 1 to Period 2 (Table 2).
Nutrient Data and Physical Activity
The nutrient content of the diet was determined for kilocalories, protein, calcium, potassium, phosphorus, iron, riboflavin, thiamin, niacin, ascorbic acid, vitamin A and vitamin D. The nutrient intake of the subject was compared by percentage of RDA for age. The means and standard deviation are presented for Periods 1 and 2 in Table 4. Calorie intakes changed very little from Period 1 to Period 2 (Table 4). When based on calories per centimeter of height, the caloric intake averaged 51% of RDA. Height was used as a reference since children with MM have a tendency to be shorter than normal for their age.
Calcium intake of children with MM ranged from 17 to 110 percent of the RDA. Only five children had calcium intakes over 51% of the RDA. However, calcium intake improved from 63% to 69% of the RDA from Period 1 to Period 2. Vitamin D intake averaged 57% and 31% of the RDA in Period 1 and Period 2, respectively, although subjects slightly increased their sunshine exposure. Dietary iron increased from 58% in Period 1 to 61% in Period 2 (Table 4).
Physical activity and percent of body fat also had a negative significant correlation (r=-0.840). The means of LBM and physical activity increased from Period 1 to Period 2, and the correlation with physical activity was higher than that with calories or growth (Tables 2 and 3). Percentage of body fat and percentage of calories remained the same or only increased slightly during the six months, but again, not significantly, presumably due to the short duration of the study (Tables 2 and 3).
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DISCUSSION
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In this study, the effects of growth, diet and physical activity on the body composition of the child with MM over six months were assessed. Physical activity had the highest partial correlation with change in LBM. Since Periods 1 and 2 were not significantly different, correlation coefficients were used from Period 1 (Table 5). The percent of LBM of the subjects showed a significant correlation with the physical activity of the subjects (Table 2). Thus, the children achieving the largest degree of independence and self-care had the greater amount of LBM. In order to achieve larger increases in percentage of LBM and thereby increased caloric needs, a child with MM should be trained from birth to become independent by increasing physical activity and strengthening physical abilities. In the present study using an adolescent female with MM, the LBM was somewhat lower (about 5 gm) and the percent of body fat somewhat higher (about 5%) than these were in Bandini’s findings [9]. The studies involve two different methods of body composition, however (Table 6).
LBM and creatinine excretion and potassium content and creatinine excretion were both significantly correlated (Table 2), indicating that, even though patients with MM may have some renal damage, a relationship between total muscle mass and creatinine exists. Destruction of nephrons is compensated for by the remaining nephrons’ excreting more creatinine per unit volume of glomerular filtrate before the onset of damage (unless in late-stage renal disease) [6]. Creatinine was not significantly correlated with age for children with MM, as in children in the general population. Height had the highest correlation coefficient. Potassium content was found to be approximately 50% less than that in a child without MM of the same age.
In MM the percentage of body fat was significantly correlated with the total skinfolds. (The thorax and abdomen skinfolds have not been reported earlier but were found to be significantly correlated for this population.) The subscapular skinfold was poorly correlated with percentage of body fat; this finding was in agreement with Forbes [12] and Bandini [9] but in disagreement with Roberts [7]. The waist circumference was correlated with percentage of fat, indicating that fat in the child with MM accumulates around the hip and lower areas of the body below the neurological lesion. Research indicates that fat accumulation occurs on non-active parts of the body more than on active parts [17, 18]. The use of anthropometric measurements (thorax and abdominal skinfolds) and waist circumference is recommended for the child with MM in determining body fat content because these measurements were significant at the 5% and 10% levels, respectively. The ease of self-measurement (particularly the waist circumference) by the child and the low cost of obtaining the measurements warrant their use, especially since weighing may be difficult [6]. Keeping children at the 25th percentile on the NCHS grid for age or at the 50th percentile on the preliminary MM grids appears reasonable [4, 11].
To reduce body fat content, levels as low as 600 kcal to 1200 kcal a day may be needed, depending upon physical activity. For example, the RMR was performed on one subject (number 14) and found to be only 600 calories per day. An increase in physical activity was recommended, such as crawling upstairs to the bedroom rather than sleeping on the first floor, to use more calories, thus allowing the subject to increase LBM and RMR and, in turn, to increase caloric needs. Calorie intakes below 800 calories usually require a vitamin/mineral supplement. RMR or resting energy expenditure (REE) is proportionate to potassium content or LBM, the RMR of the child with MM would be approximately 50% of that of a child without MM based on age. The lower basal caloric needs in addition to lack of physical activity of the majority of the subjects could account for the extremely low calorie needs. The TEE is similar to the RMR or REE, unless physical activity is increased. Based on data from this study, caloric needs determined by LBM or potassium content would be reduced to approximately half those of the child without MM (about nine kcal/cm of height for maintenance and approximately seven kcal/cm of height for weight loss if the child with MM is six years of age or over and minimally active). This may also be true for the child with MM at three or four years of age when walking should begin, but limbs fail to grow adequately [19].
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CONCLUSION
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In this study, the LBM of a child with MM averaged 50% of that of a child without MM, indicating that calories and perhaps some other nutrient needs of a child with MM are 50% lower than those of a child without MM. This figure could be as low as nine kcal/cm of height for maintenance and seven kcal/cm of height for weight loss at age six or older. Since physical activity increases LBM or active muscle tissue and thereby calorie requirements, exercise such as swimming or self-movement for the child with MM beginning in infancy must be encouraged. It should increase even further by age two and three, when walking would normally begin. Thorax and abdominal skinfolds should be determined as self-controls. Waist circumference should be used by the client as early as possible for independence and motivation to prevent obesity. The ease and convenience of obtaining these measurements make them attractive to both the client and the clinician in assessing and monitoring the child’s LBM. Due to the number of fractures occurring in these children, the importance of using adequate fat-free milk fortified with vitamin D should be emphasized from a young age (approximately two years) into adulthood along with 15 minutes of sunshine exposure per day. Dietary sodium should be reduced as it produces increased urinary calcium loss. Dietary iron needs should be addressed in counseling sessions. Simply, diets should be low calorie, but nutrient dense.
Nutritionists and dietitians need to be available to monitor nutrient intakes, calorie expenditures, anthropometry and biochemistries of children with MM and to encourage prevention of obesity [20, 21].
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ACKNOWLEDGMENTS
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The authors wish to thank Professor Richard Bozian, M.D., Professor James Stevens, Ph.D., Vanessa Laffert and Carolyn Kelley for their assistance with this manuscript.
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FOOTNOTES
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This project was supported in part by Grant No. MCJ-399156-09-0 awarded by the Maternal and Child Health Bureau (Title V, Social Security Act), Health Resources and Service Administration, Public Health Service, Department of Health and Human Services.
Received October 1, 1998.
Accepted April 1, 1999.
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REFERENCES
|
|---|
- Molnar D, Schutz Y: The effect of obesity, age, puberty and gender on resting metabolic rate in children and adolescents.
European Journal of Pediatrics
156:
376–381,
1997.[Medline]
- Parizkova J: Age trends in fat in normal and obese children.
J Applied Physiol
16:
173–174,
1961.[Abstract/Free Full Text]
- Blahd WH, Casses B, Lederer M: Body potassium content in patients with muscular dystrophy.
Ann NY Acad Sci
110:
282–290,
1963.
- Ekvall S., Myelomeningocele: Nutrition implications.
Top Clin Nutr
3:
41–54,
1988.
- Edelman IS: The role of extrarenal transport mechanisms in the regulation of the body potassium content.
Ann NY Acad Sci
110:
704–710,
1963.
- Welle S, Thornton C, Totterman S, Forbes G: Utility of creatinine excretion in body-composition studies of healthy men and women older than 60 y.
Am J Clin Nutr
63:
151–156,
1996.[Abstract/Free Full Text]
- Roberts D, Shephard RW, Shephard K: Anthropometry and obesity in myelomeningocele.
J Paediatr Child Health
27:
83–90,
1991.[Medline]
- Shurtleff DB, Lamers J, Goiney T, Gordon L: Are myelodysplastic children fat? Anthropometric measures: a preliminary report.
Spina Bifida International
4:
1–21,
1982.
- Bandini LG, Schoeller DA, Fukagawa NK, Wykes LF, and Dietz WH: Body composition and energy expenditure in adolescents with cerebral palsy or myelodysplasia.
Pediatric Research
29:
70–77,
1991.
- Dietz WH: Critical periods in childhood for the development of obesity.
Am J Clin Nutr
59:
955–959,
1994.[Abstract/Free Full Text]
- Ekvall SW: Myelomeningocele. In Ekvall S, (ed):
"Pediatric Nutrition in Chronic Diseases and Developmental Disorders." New York: Oxford University Press, pp
107–113,
1993.
- Forbes GB: Estimation of lean body mass and fat. In
"Human Body Composition: Growth, Aging, Nutrition, and Activity." New York: Springer Verlag, pp.
28–50,
1987.
- Bonsnes RW, Taussky HH: On the calorimetric determination of creatinine by the Jaffe reaction.
J Biol Chem
158:
581–591,
1945.[Free Full Text]
- Steinkamp RD, Cohen ML, Gaffey WR, McKey T, Bron G, Siri WE, Sargent TW, Isaacs E: Measures of body fat and related factors in normal adults. II. A simple clinical method to estimate body fat and lean body mass.
J Chron Dis
18:
1291–1307,
1965.[Medline]
- Talbot MB: Measurement of obesity by the creatinine coefficient.
Am J Dis Child
55:
42–50,
1958.
- Flynn MA, Nolph GB, Baker AS, Martin WM, Krause G: Total body potassium in aging humans: a longitudinal study.
Am J Clin Nutr
50:
713–717,
1989.[Abstract/Free Full Text]
- Lee MMC: Thickening of the subcutaneous tissues in paralyzed limbs in chronic hemiplegia.
Hum Biol
31:
187–195,
1959.[Medline]
- Whitaker RC, Wright JA, Pepe MS, Seidel KD, Dietz WH: Predicting obesity in young adulthood from childhood and parental obesity.
New England Journal of Medicine
337:
869–873,
1997.[Abstract/Free Full Text]
- Belt-Niedbala BJ, Ekvall S, Cook CM, Oppenheimer S, Wessel J: Linear growth measurement: A comparison of single arm-lengths and arm-span.
Dev Med Child Neur
28:
319–324,
1986.[Medline]
- Ekvall SW, Bandini L, Ekvall V: Obesity. In Ekvall S (ed):
"Pediatric Nutrition in Chronic Diseases and Developmental Disorders." New York: Oxford University Press, pp
166–172,
1993.
- La Follette Atencio P, Ekvall SW, Oppenheimer S: Effect of level of lesion and quality of ambulation on growth chart measurements in children with myelomeningocele: A pilot study.
J Am Diet Assoc
92:
858–861,
1992.[Medline]
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ABSTRACT
INTRODUCTION
