If any type of pain does not go away in a reasonable period of time (i.e. 3-6 months), it becomes chronic pain, and requires different modalities of treatment. Traditional medicine does an excellent job with acute pain, but often performs poorly with chronic pain. Pills, physical therapy, surgical intervention, psychiatric evaluation/counseling, and "Learning to live with it" are the standard treatment options for chronic pain patients.
Chronic symptoms are controlled by the autonomic nervous system, consisting of the sympathetic and parasympathetic nervous system, which may demand long-term care without promise for progress or cure. This may force life style changes that were previously enjoyed, and causing one to easily fall into depression.
Marijuana is being used to minimize pain. [Grinspoon, L., and Bakaler, J.B. "Marijuana as Medicine." Journal of the American Medical Association 1995; 273(23): pp1875-76.]