The use of splints, elastic bandages, neoprene sleeves, and various braces for knee injuries is controversial. When to wear these devices and for how long are subjects of current research.
A proper diagnosis is the first step in knowing how to treat an injury. For example, elastic ace wraps are used for sprains to help reduce swelling in the first 24 hours. Knee support is sometimes recommended for anterior cruciate ligament injuries, especially if surgery is delayed. Talk with your doctor to find out whether extra support is necessary in your case.