A severe sprain involves the complete tearing of one or more of the ankle ligaments. Patients with a severe ankle sprain are often unable to bear weight on the injured ankle. A golf ball sized lump of bruising can be seen over the painful area in severe injuries. In addition to pain and swelling, patients suffering from severe ankle sprains have increased stiffness and instability in the injured joint. Treatment of a severe ankle injury begins with one or two weeks of non-weightbearing with immobilization in either a cast or removable pneumatic boot.