Hoffa's pad is another name for the fat pad that sits below the knee cap. When it is irritated or inflamed, one can experience extreme tenderness around and below the knee cap. It's a common condition with people who have hyperextended the knee, which is when the knee is forced backwards beyond its natural limits.
Treatments for Hoffitis include the use if ice, rest, anti-inflammatories, taping, aquatic therapy and physical therapy.