Achondroplasia is a defect in the bones’ growth that results in disparity in the proportion of the individual’s body. Dwarfism is characterized by an individual that appears shorter than the average population of the same age. The individual affected by achondroplasia has an average length upper trunk and shorter extremities. This condition occurs in 1 out of 25,000 births in the United States alone and affects both males and females.

Studies have shown that the majority of cases of achondroplasia are not linked with heredity. However, if one parent has the condition, there is approximately a 50% likelihood that the child will be affected. If both parents have achondroplasia, there is a 50% chance of the child carrying the gene that causes the condition. Some cases have inherited achondroplasia so severe that the baby succumbs to death in utero.


The two types of achondroplasia are:

  • Disproportionate achondroplasia is the case among individuals with an averagelength upper trunk but relatively short extremities.
  • Proportionate achondroplasia- presents as the short trunk, short limbs, and extremities.



The person with achondroplasia has the characteristic “dwarf-like” appearance. As depicted in some movies, they appear as individuals with one or two characteristics listed below:

  • Tiny and stubby extremities both aboutthe arms and legs
  • Big headin proportion to that of the rest of the body
  • The eyes and the nose tend to “sink” into the facial area
  • Presence of a hunched over posture. This results from the abnormal development of the curvature of the spine resulting ina C shaped deformity
  • The knees can either come together in the midline of the body (knock knee), or it can spread out away from the body (bow-legged)
  • Recurrent infection involving the middle ear- this is a result of the obstruction of the outflow tract of the Eustachian tube
  • Noisy breathing, especially during sleeping or there,is several minutes when the individual has several minutes of apnea


Achondroplasia can be diagnosed intrapartum with the aid of ultrasonography. Findings include the excessive length of the infant’s extremities, abnormally large skull concerning the body size.

Gene testing for the presence of FGF3 gene mutation can be done by getting a sample through amniotic fluid sampling. In cases wherein a homozygotic trait is seen, it is presumed that the fetus will be born dead.

Radiologic imaging to assess the presence of the characteristic features of achondroplasia may be done. Signs include the unusually large size of the foramen magnum, the spinal canal’s small orifice, and square-shaped iliac bones.


Treatment options for achondroplasia involve the giving of growth hormone therapy. Although studies have shown that the treatment’s effectiveness is only limited to a year within the start of the procedure because after that period, bone growth plateaus and there is no more considerable growth that will occur.

Another treatment that is still controversial as of this time is the use of bone lengthening surgery.

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