The condition dwarfism or restricted growth is typically characterized by short stature, with an adult height of less than 4 feet 10 inches (147 cm). Over 200 different disorders exist that can cause restricted growth and aside form short stature, symptoms vary considerably depending on the cause of the condition. Generally these disorders can be divided into those that cause either disproportionate short stature or proportionate short stature.

Disproportionate short stature (DSS)

In this form of dwarfism, one or more body parts are larger than the other and in most cases the trunk is larger than the limbs. The head is usually disproportionately large compared with the rest of the body. The majority of dwarfism cases are of the DSS form and the most common cause of DSS is achondroplasia. Typical features of this condition include:

• A trunk of average size
• Short limbs, particularly the upper portion of the legs and arms
• Short fingers with thumbs and ring fingers set wide apart
• Poorly mobile elbows
• Bowed legs
• Large head with flat nose bridge and high forehead
• Curved lower spine (lordosis)
• Balance problems
• Osteoarthritis of the bones and joints
• Sleep apnea causing snoring and interrupted sleep
• Excess fluid in the brain cavities (hydrocephalus)
• Average height is around 4 feet or 122 cm

Proportionate dwarfism

Here, all parts of the body are small but they are in proportion to each other. Disorders that cause PSS affect overall growth and several bodily symptoms are often poorly developed. Usually, PSS is simply caused by having small parents. Another cause of PSS is growth hormone deficiency, caused by the pituitary gland failing to produce sufficient levels of growth hormone. Signs of this condition include:

• Slow growth rate for age
• Delayed or absent sexual development
• Height below the third percentile
• Low blood sugar level