Estimation of Length or Height in Infants and Young Children Using Ulnar and Lower Leg Length with Dual-energy X-ray Absorptiometry Validation

AIM: We compared the accuracy and reproducibility of using ulnar and lower leg length measurements to predict length and height in infants and children aged 0 to 6 years. METHOD: Length/height and ulnar and lower leg length were measured in 352 healthy preterm and term-born children (167 males, 185 females) (Mean age= 2.6±1.6 years). Ulna length was measured as the distance between the proximal olecranon process and the distal styloid process of the ulna. Tibia length was measured as the distance from the proximal aspect of the medial condyle and the most distal aspect of the medial malleolus of the tibia using a segmometer. Length measurements were taken using an infant length board in children less than 24 months of age, whereas a portable stadiometer was used to measure height in older children. Equations were developed using ulnar and lower leg length and age. Intra- and inter-examiner variability (n=167) was calculated, and dual-energy X-ray absorptiometry scans (n=126) were used to determine accuracy of limb lengths. RESULTS: Ulnar and lower leg length explained over 95% of the variability in length/height in term infants and children, but less in preterm infants (R(2) =0.80-0.87). In preterm infants, the limits of agreement (LOA) for males were -2.44 to 2.44cm and -2.88 to 2.88cm for the ulna and lower leg respectively, whereas the LOA for females were -1.90 to 1.90cm and -1.87 to 1.87cm respectively. In older children, the LOA for males were -5.53 to 4.48cm and -5.59 to 4.62cm for the ulna and lower leg respectively, whereas the LOA for females were -5.57 to 5.01cm and -6.02 to 5.02cm respectively. Intra- and inter-examiner variability was low for all measurements in both sexes and age groups. INTERPRETATION: Length and height measurements using infant length board or stadiometer are reproducible. Because of the wide limits of agreement, estimation of length and height in children using ulnar and lower leg length is not an acceptable alternative to traditional methods

IGF-1 and IGF-Binding Proteins and Bone Mass, Geometry, and Strength: Relation to Metabolic Control in Adolescent Girls With Type 1 Diabetes

Children and adolescents with poorly controlled type 1 diabetes mellitus (T1DM) are at risk for decreased bone mass. Growth hormone (GH) and its mediator, IGF-1, promote skeletal growth. Recent observations have suggested that children and adolescents with T1DM are at risk for decreased bone mineral acquisition. We examined the relationships between metabolic control, IGF-1 and its binding proteins (IGFBP-1, -3, -5), and bone mass in T1DM in adolescent girls 12–15 yr of age with T1DM (n = 11) and matched controls (n = 10). Subjects were admitted overnight and given a standardized diet. Periodic blood samples were obtained, and bone measurements were performed. Serum GH, IGFBP-1 and -5, glycosylated hemoglobin (HbA1c), glucose, and urine magnesium levels were higher and IGF-1 values were lower in T1DM compared with controls (p < 0.05). Whole body BMC/bone area (BA), femoral neck areal BMD (aBMD) and bone mineral apparent density (BMAD), and tibia cortical BMC were lower in T1DM (p < 0.05). Poor diabetes control predicted lower IGF-1 (r2 = 0.21) and greater IGFBP-1 (r2 = 0.39), IGFBP-5 (r2 = 0.38), and bone-specific alkaline phosphatase (BALP; r2 = 0.41, p < 0.05). Higher urine magnesium excretion predicted an overall shorter, lighter skeleton, and lower tibia cortical bone size, mineral, and density (r2 = 0.44–0.75, p < 0.05). In the T1DM cohort, earlier age at diagnosis was predictive of lower IGF-1, higher urine magnesium excretion, and lighter, thinner cortical bone (r2 ≥ 0.45, p < 0.01). We conclude that poor metabolic control alters the GH/IGF-1 axis, whereas greater urine magnesium excretion may reflect subtle changes in renal function and/or glucosuria leading to altered bone size and density in adolescent girls with T1DM

Generations Exercising Together to Improve Fitness (GET FIT): A Pilot Study Designed to Increase Physical Activity and Improve Health-Related Fitness in Three Generations of Women

A 6-month home-based (HB) physical activity program was compared to a control (CTL) condition in terms of effect on physical activity and health-related fitness in three generations of women (daughter/mother/maternal grandmother). Volunteers were randomly assigned to a HB or CTL condition. HB participants (n = 28) were asked to participate in lifestyle, aerobic, muscular strength, and flexibility activities at least 3 times per week and they completed 73% of the recommended PA bouts. CTL condition participants (n = 9) were asked to continue their usual pattern of physical activity. Changes in physical activity were measured pre- and post-intervention using the Physical Best questionnaire and pedometer step counts (3-day average). Changes in health-related fitness were assessed using Fitnessgram tests. Group × Time interactions were significant for changes in participation in flexibility activity (d/wk) and steps/day, indicating that the HB group experienced significant positive changes in the expected direction (+305% and +37%, respectively), while the CTL group regressed (−15% and −13%, respectively). The G × T interaction for mile time was significant, although not in the expected direction (CTL group \u3c by 14% and HB group \u3c by 5%). Findings should be interpreted with caution due to several limitations of the study, but several suggestions are made for more effectively studying this topic in the future

A 6-Month Pilot Study of Effects of a Physical Activity Intervention on Life Satisfaction with a Sample of Three Generations of Women

This pilot study assessed possible changes in Life Satisfaction across three generations of women after a 6-mo. physical activity intervention. The primary purpose of the study was to test the study design and discover critical issues that should be controlled for or changed in a follow-up study. A quasi-experimental design was used to assign randomly a convenience sample of participant triads into two groups: a home-based group (n=27) and a control group (n=9). Daughters were pre-menarcheal (n=13,M=10.1 yr., SD=1.5), mothers were premenopausal (n=11, M=10.1 yr., SD=1.5) and grandmothers were post-menopausal (n=1, M-61.5 yr., SD=4.4). Life Satisfaction was measured using the Safisfaction with Life Scale. Participation in physical activity was measured using the Physical Best Physical Activity Questionnaire and a pedometer to count the number of steps taken per day. Compared with the control group, participants in the home-based group generally increased physical activity but their scores for Life Satisfaction did not increase. Recommendations concerning the study design, reducing limitations, and hypotheses for further study are given

Can Physical Activity Interventions Change Perceived Exercise Benefits and Barriers?

This study examined changes in physical activity and perceived exercise benefits, barriers, and benefit-to-barrier differences in mothers and daughters who participated in 12-week home-based (HB) and university-based (UB) physical activity interventions. Two (group) by two (time) repeated measures ANOVAs and effect sizes showed an increase in physical activity in both groups. Mothers in both groups reported a significant decrease in exercise barriers (p = .01, ES = .41). Exercise benefits and barriers did not change for daughters, nor did exercise benefits change for mothers. These two interventions were successful at increasing physical activity, but changes in EBBS scales differed by age and point in time measures were taken. This information can be used to plan better interventions for girls and women

Peripheral quantitative computed tomography in children and adolescents: The 2007 ISCD pediatric official positions

Peripheral quantitative computed tomography (pQCT) has mainly been used as a research tool in children. To evaluate the clinical utility of pQCT and formulate recommendations for its use in children, the International Society of Clinical Densitometry (ISCD) convened a task force to review the literature and propose areas of consensus and future research. The types of pQCT technology available, the clinical application of pQCT for bone health assessment in children, the important elements to be included in a pQCT report, and quality control monitoring techniques were evaluated. The review revealed a lack of standardization of pQCT techniques, and a paucity of data regarding differences between pQCT manufacturers, models and software versions and their impact in pediatric assessment. Measurement sites varied across studies. Adequate reference data, a critical element for interpretation of pQCT results, were entirely lacking, although some comparative data on healthy children were available. The elements of the pQCT clinical report and quality control procedures are similar to those recommended for dual-energy X-ray absorptiometry. Future research is needed to establish evidence-based criteria for the selection of the measurement site, scan acquisition and analysis parameters, and outcome measures. Reference data that sufficiently characterize the normal range of variability in the population also need to be established