Which type of dwarfism affects only the long bones? they have a normal size, head and torso.

Achondroplasia affects the long bones and individual has normal size, head and torso.

Explanation:

Achondroplasia dwarfism may be defined as the form of dwarfism in which the conversion of bone to cartilage is defected. This is the most common form of dwarfism.

Achondroplasia dwarfism mainly affects the long bones of an individual as there is problem in the conversion of cartilage to bone. The individuals have short arms and legs but they have normal head and torso size. The individuals has height around 4 feet.