Final answer:
Malunion is demonstrated when a patient's leg healed incorrectly due to the way the cast was applied.
Step-by-step explanation:
When a patient's leg heals incorrectly because of the way the cast had been applied, it is an example of malunion. Malunion refers to the improper healing of a bone after a fracture, which results in a deformity or functional impairment. In this case, the cast was not applied correctly, causing the bones in the leg to heal in the wrong position.