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 24th Amendment is one that arose due to yet another Amendment to the United States Constitution, the Fifteenth Amendment. The 15th Amendment granted men the right to vote, prohibiting the Government from using race, color, or previous condition of servitude as a means to deny such a right.