-genetic disorder that is an X-linked recessive trait
-increased deformity and disability
-Alterations of a protein called dystrophin that helps keep muscle cells intact
-Characterized by progressive muscle weakness starting with the proximal muscles then progresses to the distal muscles, usually notice around age 3
-S/S include difficulty jumping, walking, running, walking, enlargement of the calf muscles, waddling gait, and lumbar lordosis. Later on, the heart and respiratory muscles are affected as well
-weak lower muscles, usually use upper extremities