All Anthropometry Formulas and values in Paediatrics: Height, Weight, Head circumference

Normal Anthropometric values at birth 

Anthropometry formula for expected parameters in pediatrics

Normal Anthropometric Values at Birth

Parameter	Range	Normal for easy memory
Weight	2.5-3.5kg	3 kg
Length	45-55 cm	50cm
Head circumference	33-37cm	35cm

Calculate body surface area from the weight (kg)

Body Surface area = (4w+7)/(w+90) m²

Ideal weight gain

Age	Expected weight	Rate of weight gain  g/day
Up to 4 months	3-6kg	30g/day
4-8 months	6-8kg	20g/day
8-12 months	8-10 kg	15g/day

Age	Rate of weight gain  g/week
3 months	200 g/week
4 – 6 months	150 g/week
7 – 9 months	100 g/week
10 – 12 months	50 – 75 g/week
1 – 2 years	40 g/week
2 - puberty	30 g/week

All you need to remember for baby weight 

Age	Rate of weight gain
Up to 3 months	30  g/day
3 months to 1 year	400 g/month
3-7 years	2 kg/year
7 years to adolescence	3kg/year

The weight of any baby should multiply in the following rate ideally

Birth Weight (x)	Time	Examples (2.5kg )
2x (Doubles)	5 months	5kg
3x (Triples)	1 year	7.5kg
4x (Four Times)	2 years	10kg
5x (Five times)	3 years	12.5kg
6x (Six times)	5 years	15kg
7x (Seven times)	7 years	17.5kg
10x (Ten times)	10 years	25kg

Formula to calculate expected weight at certain age

Age	Weech Formula
3-12 months	(Age in months + 9) / 2
1-6 years	Age(years)x2 + 8
7-12 years	(Age in years X 7- 5)/2

Inability to gain adequate weight, may be undernutrition. Learn about marasmus and kwashiorkor 

Measurement and calculation of Height

Age	Length at birth
Birth	50cm
3 months	60cm
1 year	75cm
2 years	90cm
4-5 years	100cm
5 years to 10 years	5cm/years
Adolescence	8 cm/year for girls during 12-16 years 10cm/year for boys during 14-18 years

Expected length gain in pediatric

Weech Formula for expected height from 2 years to 12 years

Expected height = age in years x 2 + 77 cm

Rate of gain of length/ height

Age	Gain in length/height
Up to 3 months	3.5cm/month
6-9 months	1.5cm/month
9-12 months	1.3cm/month
2-5 years	6-8cm/year
5 years to 10 years	5cm/years
Adolescence	8 cm/year for girls during 12-16 years 10cm/year for boys during 14-18 years

Head Circumference

Birth	35 cm
3 Months	40 cm
1 years	45 cm
2 years	48cm
5 years	52cm

Rate of growth of Head circumference

Up to  3 months	2 cm/month
3 months – 1 year	2cm/ 3 months
1-3 years	1cm/ 6 month
3-5 year	1cm/ year

Dines formula to estimate HC at 1 years

(HC at birth(cm) + 9.5 ± 2.59)/2 

Learn about abnormality in Head circumference and their causes (Microcephaly, macrocephaly). 

Normal Values of Head circumference and Chest circumference

Chest Circumference 

HC > CC @ Birth by 3cm

HC = CC @ 9-12 months

HC< CC after 1 years

Mid Arm Circumference (MUAC)

Increase in first year       11cm - 16cm

1-5 years                         16cm - 17cm 

Sources: http://www.adsa.org.za/Portals/14/Documents/Clinical20Guideline20Anthropometry.pdf

Essential pediatrics OP Ghai 

Meherban singh Clinical Methods

Plantar Reflexes and its equivalents with youtube video

The Normal Plantar Reflex

Nocireceptive relfex
Root value : S1

Stroking the lateral aspect of the sole with a sharp object produces (In increasing order of stimulus)

1. Flexion of all five toes 
2. Dorsiflexion and inversion of foot (with stronger stimuli)
3. Contraction of adductors of thigh, sartorius and tensor fascia lata.

Different resposnses

Normal: Flexor/Downgoing plantar reflex  (as mentioned above)

Babinski Sign (Extensor/ upgoing plantar reflex)

Components of extensor reflex are 

1. Dorsiflexion of great toe (precedes all other movements)
2. Fanning (outspreading) and extension of remaining four toes 
3. Dorsiflesion of ankle. flexion of knee and hip joint 
4. Contraction of fascia tensor lata 

Equivocal/incomplete/variable response

No Response 

Withdrawal reflex

Preparing for Exam : Check if you have all necessary instruments necessary for CNS examination 

Plantar Equivalents 

Oppenhiems sign 

Heavy pressure applied by thumb and index finger over the medial aspect of tibial (shin) from above down ward

Gordon Reflex

Squeezing or applying pressure over the calf muscle 

LMN UMN lesion of bladder 

?Shefer sign/?Schaefer Sign 

Squeezing the Achilles tendon 

Know the physiology behind the upper motor and lower motor neuron lesion.

Chaddock Sign 

Striking the skin just below lateral malleolus and moving anterior /in circular fashion 

Bing sign 

Prinking the dorsum of foot or great toe by a pin

Moniz sign 

Forceful passive flexion of ankle 

Gonda sign 

Forceful stretching or snapping of distal phalanges of euther the 2nd or the 4th toe 

Brissauds reflex

Contraction of tensor fascia lata in amputated/absent great toe patients or complete paralysis of extensors of toe

Rossimillo Sign 

Tap the ball of the foot or flick the distal phalages of toe into extension nad allow them to fall back to their normal position produces  PLANTIFLEXION of ALL phalanges. (Only sign with Plantiflexion of great toe)

Equivalent of Hoffmann's Sign 

Hoffmann sign 

Flex the distal interpalangeal joint of the middle finger and now flick it down suddenly, response is brisk flexion and abduction of thumb as well as flexion of the other fingers.

Videos

All reflexes in one video

Sources
http://www.ncbi.nlm.nih.gov/books/NBK397/
www.youtube.com
Harrisons Text Book Of Medicine
Bedside Clinics In Medicine 6e (Arup Kumar Kundu)