A sprain happens when the connection between bones called ligaments become overstretched. There are different degrees of stretch. A sprain right after injury may look purple like a bruise, and likely be painful to touch and swell up.
Immediate treatment of a sprain uses the guiding acronym RICE for what to do. Rest, Ice, Compression, Elevation. The goal for treatment if it’s a minor sprain, just a stretch of the ligament, is keeping it mobile with rotating the ankle. Severe sprains may require bracing. The joint will be painful to place weight through, so crutches are usually given to people with sprains and used for several weeks to reduce weight placed on the joint.