Sprains are acute injuries -- they are brought on by an event such as a fall or sudden twist. The pain you experience is due to the damaged tissues associated with that event. Sprains also can be brought about by repeated stress to overused joints in sports and other activities. While most of the time sprains occur in joints of the extremities -- for example, the ankle joint -- neck sprain is also common.
Sprains, (as well as strains) are measured in degrees. First-degree sprains are minor, and the best thing to do for them is RICE: rest, ice, elevation and compression. If you sprain your back, try icing the area and resting. Aspirin or other types of NSAIDs might help as well. The goal is to control inflammation.
At the other end of the spectrum, third-degree sprains involve complete rupture of all the fibers of a ligament. Third-degree sprains are serious injuries, and can cause a lot of pain and inflammation, as well as instability of the joint. If you think you have a third-degree sprain, the first thing to do is to immobilize the joint. Then consult your physician immediately. Keep the joint immobilized until your doctor has evaluated the injury.
In any case, the swelling that occurs in response to the injury may cause problems such as decreased range of motion and pain. Physical therapy can address this and help restore your back to function.
American Academy of Orthopedic Surgeons. Neck Sprain. AAOS Website. May 2000.
Magee, D.J. Orthopedic Physical Assessment. 4th edition. Saunders Elsevier. 2006. St. Louis, Mo.
Mosby's Medical Dictionary. 7th edition. 2006. Mosby Elsevier. St. Louis, Mo.