Knees are a very common area of injury given the muscles, tendons and ligaments are constantly in use and are often strained in athletic endeavours. The knees are also your bodies natural lever where every extra pound or kilogram of weight gain above the knee puts four times that weight gain in pressure to the knee.
Injury, weight gain and age can often cause damage to the knees and a knee brace is needed to shift weight from the injured or damaged area of knee. The knee brace also adds stability which can reduce both pain and swelling. Knee braces are commonly used after knee surgery, for ACL tears, for arthritis, for ligament tears and for general muscle soreness and inflammation.
For more minor injuries and discomfort, knee support can also come in the form of compression sleeves and wraps, which offer some relieve but not the same support as a knee brace.