Which term describes the shortening of the proximal portion of a limb?

Which term describes the shortening of the proximal portion of a limb?

• A. Rhizomelia
• B. Acromelia
• C. Mesomelia
• D. Phocomelia

Answer: (A)

Shortening of the portion of a limb that is closest to the body is described as rhizomelia. The limb is divided into proximal, middle, and distal segments; the proximal segment includes the humerus and femur, so when that part is shortened, the term rhizomelia applies. This differs from mesomelia (shortening of the middle segments like forearm or lower leg bones), acromelia (shortening of the hands and feet, the distal elements), and phocomelia (severely shortened limbs with hands/feet near the trunk).

Shortening of the portion of a limb that is closest to the body is described as rhizomelia. The limb is divided into proximal, middle, and distal segments; the proximal segment includes the humerus and femur, so when that part is shortened, the term rhizomelia applies. This differs from mesomelia (shortening of the middle segments like forearm or lower leg bones), acromelia (shortening of the hands and feet, the distal elements), and phocomelia (severely shortened limbs with hands/feet near the trunk).