A hyperextended knee can damage ligaments, cartilage and other stabilizing structures in the knee. Young children have softer bones because they're still growing, so a hyperextended knee can result in a chip of bone being pulled away from the main bone when the ligaments stretch too far.
Al Capone is one of the most famous prisoners of Alcatraz. Capone was on the first trainload of prisoners to the new federal prison located on Alcatraz Island. In 1934, Capone became known as prisoner number 85. In true Capone style, he immediately tried to manipulate the system to get special treatment here.
That's why Al Capone ended up spending much of his Alcatraz sentence in the Alcatraz hospital. Eventually, having served six years and eight months of his 10-year sentence, with the remainder of the time taken off as good time for good behavior, Capone's felony tax evasion sentence was completed.