These treatments cause bleeding and healing with fibrocartilage or scar cartilage which is not as resilient as normal hyaline cartilage. These treatments remain the first line of treatment for isolated lesions of articular cartilage in the knee.
The original Constitution required direct taxes to be apportioned among the states in accordance with population. An income tax is not so apportioned, so the amendment was needed to authorize such parts of the income tax as would constitute direct taxes.
The Necessary and Proper Clause is important because it affords Congress certain powers under the Constitution. The Necessary and Proper Clause, which is listed as Article I, Section 8 of the Constitution, grants Congress the authority to establish certain financial procedures, such as tax collection and imposing debts and penalties.