Final answer:
Heat application is contraindicated over scar tissue because it can lead to inflammation and further damage to the tissue.
Step-by-step explanation:
Heat application is generally contraindicated over scar tissue. Scar tissue is formed during the healing process and is fibrous and less elastic than normal tissue. Applying heat to scar tissue can increase blood flow to the area, which may lead to inflammation and further damage to the tissue. Therefore, it is recommended to avoid applying heat directly over scar tissue.