• Mental retardation is one of most common
chronic neurologic disabiity of childhood.
• MR affects about 1-3% of population.
• Majority of cases are idiopathic.
• Most common mild MR(75-90%) often goes
• More common in lower socio-economic
DSM IV – TR Definition
Significantly below average intellectual functioning:
IQ of below 70 on an individually administered IQ
Accompanied by significant limitations in adaptive
functioning in at least 2 skill areas:
Communication, self-care, home living,
social/interpersonal skills, use of community
resources, self-direction, functional academic
skills, work & leisure, health and safety.
Onset before age 18yr.
Signs & Symptoms
• Delay in language development.
• Find it hard to remember things.
• Difficulty in learning social rules.
• Have trouble learn specific subject
• Have trouble solving problems
• Lack of social inhibitors.
• Lack of self care skills.
• Persistence of infantile behaviour .
• Unable to take higher education.
Grades of MR :
According to IQ :
• Borderline intellectual functioning70--84
• Mild mental retardation 50–69
• Moderate mental retardation 35–49
• Severe mental retardation 20–34
• Profound mental retardation Below 20
• May not be obvious in early childhood, untill they go
• In School - have poor academic performance
(difficult to differentiate from learning disability or
emotional & behavioral disorder.)
• can learn reading & mathematical skills to level of a
typical 9-12 yr child.
• Learn self care &practical skills to live independently
& earn for them self.
• obvious within 1st year of life
• Problem with social work
• Behaviourable age -8 yrs
• Academic skills – 2nd grade level
• will face difficulty in school, at home, and in the
• Need special school, but they can still progress to
become functioning members of society. As adults
they may live with their parents, in a supportive
Severe & Profound MR
• Little or no speech
• Limited abilities to manage self care.
• Require high supervision .
• Behaviourable age – 3 yrs.
• They may learn some daily activities but will
require full time care –taker.
• Denver Development Screening Test-II
• Bayley Scales of Infant Development
• BARODA PHATAK DST
• Trivendrum Developmental Screening Chart
Test for intelligence
• Binet kamat test
• Weschler’s intelligence scale for children
• Goodenough draw a man test.
Denver II Developmental Screening Test
• Most widely used test for quick routine
screening, for children upto 6yrs.
Assesses child development in all four domains
(gross motor , fine motor adaptive, language,
personal social behavior),taking 10-30 min.
• The milestones are shown in a graphical
manner & items through which the
chronological age passes are tested.
BAYLEY SCALE OF INFANT DEVELOPMENT
• Based on motor scale , mental scale and infant behaviour
• Up to 30 months of age
• Takes 30-60 minutes
• 67 motor scale ,107 mental scales
BARODA DEVELOPMENT SCREENING TEST
• Based on BSID, developed by Dr. phatak according to
baroda norms, suitable for Indian children.
• Does not require standard equipment, domains
evaluated are gross motor ,fine motor, cognitive, takes 10
Wechsler Intelligence Scale for children
• for children from 5-15yrs
– Mean score of 100 with standard deviation of 15
– Gives verbal and performance scores, takes 45-60 min.
– Broken into 12 subtests 6 each for verbal & performance abilities.
• MALIN INTELLIGENCE SCALE FOR INDIAN CHILDREN:
- Indian adaptation of WISC
- It may not give real capabilities in non school going children as mostly
influenced by formal schooling system
STANFORD BINET INTELLIGENCE SCALE
• for children>2yr.
• Include verbal ability ,perceptual skills , short
term memory & hand and eye co-ordination
• takes 45-60 minutes
• BINET – KAMAT TEST
-indian adaptation of stanford - binet scale
- also available in hindi
APPROACH TO A CHILD WITH MR
• Detailed development history.
• Antenatal history.
• Perinatal history.
• Any neurological problem: seizure, spasticity,
motor deficit, abnormal movements, vision&
• Features s/o of IEM: abdominal distension.
• F/o of hypothyroidism.
• Past history of febrile encephalopathy.
• Emotional deprivation.
• Level of indipendence.
• Scholastic performance.
• Sibling history.
• H/o temper tantrums, hyperkinesis, self
• Any h/o physical & psychological abuse.
• Lead exposure.
• Primary prevention: improvement in perinatal
care, iodistion of salt,immunisations,detection
&care of high risk pregnancies, penatal screening
• 2nd ary prevention: neonatal screening, screening
of “high risk babies” & early intervention
• Tertiary prevention: stimulation, training,&
education, vocational oppertunities.
• Support for families
• Parenteral support groups.
• No specific drugs but some symptoms can be
• Neuroleptic drugs to reduce aggressive and
antisocial behavior (phenothiazines).
• antipsychotic drugs( risperidone).
• Antidepressant drugs can improve sleep, possibly
help reduce self-injurious behavior, reduce
TAKE HOME MASSAGE
• Mental retardation is preventable in some cases.
• Most cases are idiopathic & are mild.
• Diagnosis is clinical.
• Examination for dysmorphology & detailed
neurology is of essence.
• Care rather than cure is the way of management in
most of the cases.
GROSS MOTOR: 180 degree flip
examination in infant < 8 months and gait
for > 1 year
• Supine: Note posture, abnormal ATNR, involuntary
movements with CP. paucity of movements for hemiplegia.
• Pull to sit: head lag. Sitting: Head and trunk control. Back is
straight or rounded.
• Weight bearing: scissoring, hypotonia, advanced weight
• Ventral suspension: Describe posture, low tone, increase
• Prone: Observe ability to raise head, trunk above horizontal,
1. Sucking/Rooting :( 0-4,6mths),
2. Palmer grasp; (0-3 months).
3. Placing, stepping: (0-6weeks)
4. ATNR: 2-6 Months.
5. Landau: on ventral suspension, normally extend head, trunk,
and hip. Flex head and neck, response is flexion of hip, trunk.0-6
6. Neck righting reflex: rotation of trunk 6mths-2 years.
7. Moro: 0-4 months.
8. Parachute: 6-12 months persist. Prone position, move rapidly,
face down. Will extend both upper limbs.