Chronic pain after surgery is usually defined as pain that lasts at least two months after the procedure. Chronic pain after injury or surgery is considered rare, as most pain goes away with time and treatment. However, it can still develop. This is true for patients of any age, including adults or children.  Those who experience chronic pain after an injury can develop complex regional pain syndrome (CRPS), a condition that usually affects the arm, leg, hand, or foot.

Several risk factors are believed to be behind chronic pain after injury or surgery. These include the type of procedure or injury, age (younger patients are generally more susceptible than older patients), certain preexisting conditions, mood disorders, levels of pain experienced before the surgery or injury, and medications.