The proband must have a rigorous physical examination with a careful description of all dysmorphic features outside of that which would be found in a normal population. Measurement of subjectively odd-looking features is vital; normal ranges vary with age and sex and must be placed in the context of centile charts.
Standard measurements include:
- height
- arm span
- weight
- lower segment length - from floor to upper border of pubis
- upper segment length - height minus lower segment length
- sitting height
- interpupillary distance - hyper/ hypotelorism
- intercanthal distance - telecanthus can occur when the intercanthal distance is greater than expected while the interpupillary distance is normal; mongoloid slant describes the state of the outer canthi being above the inner canthi
- head circumference - the maximum occipitofrontal circumference: brachycephaly and dolichocephaly describe the anteroposterior skull length being too short and too long respectively
- testicular volume
- ear length
Additionally, the following should be sought:
- Brushfield spots on the iris, present in 20% of normal babies
- a single, transverse palmar Simian crease
- epicanthic skin folds over the inner canthi
- incurving of the fifth digit, termed clinodactyly
- fingerprint abnormalities
- palate and lip abnormalities