Achondroplasia is characterized by abnormal bone growth that results in short stature with disproportionately short arms and legs, a large head, and characteristic facial features with frontal bossing, a narrow thorax, a waddling gait and mid-face hypoplasia. It is an inherited disorder of bone growth that leads to the most common type of dwarfism. It is one of the groups of disorders collectively called chondrodystrophies. Dwarfism is generally defined as an adult height of 4 feet 10 inches or less but height may vary from two feet eight inches to four feet eight inches.

 Achondroplasia is characterized by abnormal bone growth that results in short stature with disproportionately short arms and legs, a large head, and characteristic facial features with frontal bossing, a narrow thorax, a waddling gait and mid-face hypoplasia. It is an inherited disorder of bone growth that leads to the most common type of dwarfism. It is one of the groups of disorders collectively called chondrodystrophies. Dwarfism is generally defined as an adult height of 4 feet 10 inches or less but height may vary from two feet eight inches to four feet eight inches. Intelligence and life span are usually normal, though the risk of infant death from compression of the cervical spinal cord and/or upper airway obstruction is increased. Achondroplasia is inherited as an autosomal dominant trait. However, approximately 80% of cases appear to be the result of spontaneous mutations. If 1 parent has achondroplasia, there is a 50% likelihood of the infant's inheriting the disorder. If both parents have the condition, the likelihood increases to 75%. Most joints can extend more than normal. For example, the knees can hyperextend beyond the normal stopping point. Not all joints are lax in this way. To the contrary, extension and rotation of the elbow are abnormally limited. Hip extension also tends to be limited.

Symptoms

• Short, thick arms

• Short, thick legs

• Normal-size trunk

• Shortened arms

• Slightly flattened cheek bones

• Feet twisted or out of shape (clubfoot)

• Progressive development of lordosis

• Vision and hearing problems

• Limited mobility at the elbows

• Puffy hands and feet at birth and during infancy

• Heart and blood vessel defects

• Kidney problems

• No development of breasts or onset of menstruation during adolescence

• Infertility

• Undeveloped ovaries

• Redundant skin folds on the limbs

• Large head with prominent forehead (frontal bossing)

• Midface hypoplasia, saddle nose

• Trident configuration of the hands

• Gibbus in the thoracolumbar region in infants; swayback with prominent buttocks in children and adults; waddling gait

• Genu varum

Causes

Three major causes that are identified to result in dwarfism are -

• Achondroplasia

• Turner's Syndrome

• Growth Hormone Deficiency

Complications

• Spinal symptoms

• Paraplegia may occur in 2nd or 3rd decade

• Dental malocclusion

• Strabismus

• Kyphosis

• Recurrent otitis media

• Neurologic problems may occur in early adulthood

Diagnosis And Investigations

• Levels of Growth Hormones in the blood of the patient

• Family history

• Some Genetic tests are availble to reach on a definitive doagnosis and to differentiate between the probable diagnosis

• Radiographic tests like X-Ray are required to look into certain abnormalities of skull and skeleton

Treatment and Drugs

• Hormone Therapy is generally useful in patients with Turner's Sybdrome and Growth Hormone Deficiency Syndromes

• Limb Lengthening and Limb Straightening surgeries are performed in some cases