1. Postnatal Growth & Maturation

2. Growth & Maturation GROWTH – Increase in size of tissue or organ Hypertrophy – Auxetic – increased cell size – Accretionary – increased extracellular constituents Hyperplasia – Multiplicative – increased cell number MATURATION – Change in structure or function of the tissue or organ moving it closer towards the mature state

3. Methods of Studying Growth Longitudinal Study – one or more individuals are monitored over several years – time consuming, costly, attrition of sample – only way to study the dynamics of growth Cross-Sectional Study – sample many different children at same time – good for norms and bench marks

4. Count Philibert de Montbeillard Measured son every 6 months from birth to 18 years (1759-1777)

5. Standards for Growth Assessment What are the appropriate criteria for choice? – Cross-sectional / longitudinal – Local / National / International – Special populations What is available?

6. NCHS/CDC Growth Charts The most commonly used norms in North America are cross-sectional norms produced in 1977 by the National Center for Health Statistics. These were recently updated and are now presented by the Center for Disease Control (2000) CDC Growth Charts

7. Height for Age & Weight for Age

8. Weight for Height

9. BMI for Age

10. EARLY LATE Comparison of early and a late maturers who attain similar height at age 17yrs Longitudinal vs Crossectional

11. CDC Growth Charts All Racial and Ethnic Groups Combined Environmental influences appear to contribute to variations in growth more than genetic influences Inadequate sample data for racial- and ethnic-specific charts The effect of race and ethnicity on BMI- for-age is unclear

13. Caribbean Growth Data n =1697

15. Anthropometric Assessment of Special Populations A Special Population is one that can not be assessed by orthodox methodology Growth & Nutritional Status assessments

16. Treatment and Rehabilitation of Children with cerebral palsy, brain injuries and other neuromotor problems

17. S.H.A.P.E.S.

18. SELECTED MEASUREMENTS & EQUIPMENT

19. S.H.A.P.E.S. custom software – serial plotting (up to 100 measurement occasions) – anthropometric profile

20. Height Distance & Velocity Curves Adolescent growth spurt growth most rapid in first two years

21. Height distance and velocity curves for three subjects from Saskatchewan Growth Study

22. Height Velocity Curves Indicator of maturity Needs longitudinal data Other “systems” have similar curves

25. Shifting of age axis values to coincident age of PHV before averaging velocity curves

26. Means of PHV Parameters Age at takeoff – ♀: 8.5 - 10.3 yrs♂: 10.3 - 12.1 yrs Age at PHV – ♀: 11.4 - 12.2 yrs ♂: 13.4 - 14.4 yrs PHV (cm/yr) – ♀: 7.0 - 9.1 yrs ♂: 8.2 - 10.3 yrs

27. Intrauterine growth velocity is greater than during any postnatal period. Timing of birth affects growth velocities

30. Predicting Adult Size Predictions of adult stature can be made from: – heights at earlier age – parental stature – skeletal maturation

31. Four Curves of Growth

32. Differential Growth Birth to Maturity 30-40 times – Muscle, Genital Organs 20-25 times – Body, Skeleton, Respiratory System 15-20 times – heart, Liver < 5 times – Nervous System

34. Head Circumference for Age

35. Shape Changes with Age

36. Changes in Proportions

37. Somatotype Sheldon vs Heath-Carter Shape vs Size Mainly used as photographic record of child

39. Adult Size not well correlated with Birth Size

40. Adult proportions are a result of complex genetic and environmental influences Differential Growth

41. Mean Ages (yrs) at Peak Velocity Girls (n=10)Boys (n=12) Leg Length11.313.4 Stature11.814.1 Sitting Height12.414.6 Humerus Width11.914.1 Tibia Width11.113.6

42. 42

44. Adult Sexual Dimorphism No difference in proportional weight Male-Female difference greatest in: Triceps, Biceps, Front Thigh and Medial Calf Skinfolds Secondary sexual adiposity

45. Adult Sexual Dimorphism

46. Estimates of Muscularity Skinfold-Adjusted Arm Girth – Muscularity Indicator G Ga = G - (3.14xS) S = Skinfold Thickness G = Girth Ga = Skinfold adjusted Girth Ga S G

47. Girth adjusted for Skinfold at that site GirthSkinfold s.a. Arm girthRelaxed Arm GirthTriceps s.a. Chest girthChestSubscapular s.a. Thigh girthThighFront Thigh s.a. Calf girthCalfMedial Calf s.a. Forearm girthMaximum ForearmForearm s.a. Girth (cm) = Girth (cm) - (Π x Skinfold (mm) / 10)

48. Adult Sexual Dimorphism s.a. Girths are Muscularity indicators Greatest differences between the sexes in the upper body Greatest potential for hypertrophy in the upper body Muscularity profile is very sensitive to the specific activity of the individual

49. Adult Sexual Dimorphism Proportionally larger sitting height in females Males tend to have proportionally longer limbs. Biggest difference in distal segments

50. Adult Sexual Dimorphism Humerus to Femur Width differences reflects muscularity differences Males have broader and deeper chests proportionally. Classic hip-shoulder dimorphism: Males proportionally wider shoulders Females have proportionally wider hips

51. Shoulder-Hip Dimorphism 51 SexNMean Std. Deviation Biacromial/Biiliocristal BreadthMale691.440.12 Female1151.310.12

52. 52 2D:4D Ratio (2 nd digit length to 4 th digit length ratio) SexNMeanStd. Deviation Male1360.9470.029 Female1370.9650.026 2D 4D a Allison A. Bailey, Peter L. Hurda, Department of Psychology, University of Alberta. 2004

53. 2D:4D Ratio Ratio determined in utero – 2D:4D is negatively correlated with prenatal testosterone and positively correlated with prenatal estrogen Larger ratio in females – Married women had higher 2D:4D ratios than unmarried women – Significant negative associations were found between 2D:4D in men and reproductive success and significant positive relationships between 2D:4D in women and reproductive success Found to be related to: – Aggression, Competitive success, Sexual orientation

54. 54

55. Gradient vs Indicator Maturity Gradients – assessment of the relative rates of development of parts or structures of the body Maturity Indicators – Some characteristic of the body that has distinct stages of development that all normally developing children will pass through

56. Maturity Gradient

57. 57 Upper Arm Maturity Gradient

58. Three 13 year old Girls

59. Three 14 year old Boys

60. Bigness vs Maturity Do not confuse size with maturation Obesity often associated with advanced maturation skeletally but not in muscular development

61. Maturity Indicators Age of Peak Height Velocity Skeletal Age Dental Age Menarche Secondary Sexual Characteristics

62. Skeletal Age

63. Closer relationship of Age at Menarche with Skeletal Age (SA) than Chronological Age (CA)

64. Stages of Penis Development

65. Stages of Pubic Hair Development (Girls)

66. Maturity Indicator Intercorrelations

67. Synchrony of Pubertal Events