Growth Disorders and Anthropometry

Growth Disorders

• Growth is defined as an increase in cell size and number, resulting in height and/or girth increase.
• Growth monitoring involves tracking a child's growth rate against a standard using frequent anthropometric measurements. This helps assess growth adequacy.
• Anthropometry is the measurement of a person's physical parameters, then comparing them with a standard.

Anthropometric Measurements

• Weighing Scale Procedure:
  • Initial pretesting is crucial.
  • The scale must be hung on a stable support.
  • Ensure the dial is at eye level.
  • Zero the scale's pointer.
  • Undress the child as much as possible.
  • Ensure the child's feet are not touching the ground.

Measuring Height

• For infants and children under 24 months, measure lying down.
• For children 2 years and older, measure standing.
• Ensure heels, buttocks, shoulder blades, and occiput touch the measuring device, and the head is aligned so the external eye angle and external ear canal are horizontal with eyes looking forward.

Head Circumference

• A good measure of brain growth, especially in the first two years.
• Useful for monitoring low birth weight infants and those with central nervous system abnormalities.
• Normal head circumference at birth is 34-36 cm.
• Head circumference increases by 2 cm/month for the first 3 months.
• Growth slows to 1 cm/month between 3 and 6 months.
• Growth slows to 0.5 cm/month from 6 to 12 months.
• In total, head circumference increases by 12 cm during the first year.

Mid-Upper Arm Circumference (MUAC)

• MUAC indicates muscle development, correlating well with malnutrition.
• Useful for screening large populations of children for malnutrition (Shakir's tape).
• MUAC values vary based on age (1-5 years).
• It increases rapidly in the first year (11-16 cm) and remains stable (16-17 cm) between 1 and 5 years.
• A value below 11.5 cm indicates severe malnutrition.
• Colors and values associated with malnutrition:
  • MUAC less than 11.0 cm: Red (Severe malnutrition)
  • MUAC between 11.0 and 12.5 cm: Orange (Moderate malnutrition)
  • MUAC between 12.5 and 13.5 cm: Yellow (At risk or mild)
  • MUAC over 13.5 cm: Green (Well-nourished).

Body Mass Index (BMI)

• BMI is calculated by dividing weight (in kg) by height (in meters squared).
• The healthy weight range falls between the 5th and 85th percentile.
• BMI between the 85th and 94th percentile is considered overweight, indicating excess body fat or high lean body mass.
• A BMI below the 5th percentile indicates underweight.
  • Normal: <25 kg/m²
  • Overweight: 25-29 kg/m²
  • Obese: ≥30 kg/m²

Bone Age

• X-ray of the left hand and wrist to the tips of the fingers.
• Commonly used methods include the Tanner-Whitehouse method, and the Greulich Pyle method.
• Bone age is used to assess skeletal maturity.
• Bone age is helpful in predicting remaining growth potential and adult height.

Body Composition

• Calipers measure body fat.
• Body fat generally increases with age.

Flexibility

• It's the range of movement at a joint or joints.
• Factors affecting flexibility are anatomical joint structure, exercise habits, stretching habits, age, and gender.

Standard Deviation

• Standard deviation (SD) measures the dispersion of a set of data values from their average.
• A low SD indicates that most data values are close to the average, while a high SD indicates that data values are spread out.
• Formula for standard deviation (SD): $S_x = \sqrt{\frac{\sum_{i=1}^n (x_i-\bar{x})^2}{n-1}}$.
• n = The number of data points
• x = The average of the x_i
• x_i = Each data value

Percentile

• A percentile is a value that marks a particular percentage of data.
• Twenty percent of the data points are equal to or below the 20th percentile
• 99 of the values fall below the 99th percentile.
• Percentiles can be used to evaluate the relative position of a value within a set of data.

Growth Charts

• Important tools for monitoring children's growth.
• Used to compare a child's growth to the average growth of children of the same age, sex, and ethnicity.

Precocious Puberty

• Acceleration in growth occurs.
• Bone age is greater than what would be expected for the given child's chronological age.
• The final adult height might be shorter than it might have been otherwise if epiphyseal closure had not occurred earlier.

Short Stature

• Defined as height at or below the 3rd percentile for a given age, gender, and ethnicity.
• Growth velocity that is abnormally slow and significantly below what would be expected for that child's genetic potential.

Obesity

• Characterized by excessive body fat.
• Associated with cardiovascular disease, type 2 diabetes, certain cancers, and osteoarthritis.
• Diagnosed by using a BMI greater than 30 kg/m².
• Common sites for measuring body fat using calipers includes subscapular, suprailiac, triceps, thighs, and mid-calf.

Microcephaly

• A condition where the head size is significantly smaller than expected after adjusting for a child's age, gender, and ethnicity.
• Associated with intellectual disability, poor motor function, speech difficulties, abnormal facial features, and developmental disorders such as seizures and dwarfism.
• Caused by factors like congenital conditions, disruptions, or acquired circumstances both during pregnancy and after.

Macrocephaly

• An overly large head in an infant.
• Often linked to familial factors.
• It may suggest underlying brain complications.
• Head Circumference (HC) is larger than 2 standard deviations above average for that child's age, gender, and ethnicity; or greater than the 98th percentile.
• Includes conditions like hydrocephalus, brain malformation, intracranial bleeding, brain tumors, and genetic conditions such as Morquio syndrome and Hurler syndrome.