When pain is a symptom, surgery may relieve pain and save lives. Appendectomy, hip replacement, heart bypass surgery, removal of a tumor and trauma surgery are but a few well-known examples of beneficial surgical procedures. In each case a clearly identifiable source of pain (more precisely a source of pain signals going to the brain) is present that can be removed or repaired. Sometimes surgery itself may lead to chronic pain, defined as pain lasting 6 months longer than expected recovery time. Data is incomplete regarding incidence, but estimates suggest that 10% is a conservative over all figure.

In some instances, even when the source of pain is obvious and surgery has been carried out impeccably, pain can remain. Failed back syndrome is a form of chronic pain that may occur after back surgery for a herniated disc. Its cause is uncertain and most likely the result of multiple factors. Surgery to treat failed back syndrome has a poor track record.

In fact, when pain becomes chronic (and therefore quite likely a disease), the success of surgery is less apparent. The longer pain has been present, the poorer the surgical prognosis in the case of spinal problems. Cutting nerves to relieve pain is rarely successful and may lead to worse pain. Removing the stump of amputees with phantom limb pain has proven futile. In cases where surgery fails, lack of success may be the result of other factors contributing to the maintenance of pain. This has been shown to be the case with phantom limb pain, for example. Its cause lies within the brain.

Nevertheless, surgery continues to be extremely relevant to pain treatment. There are successful nerve operations. Recent neurosurgical developments offer the possibility of implanting electrodes deeply in the brain to alter directly brain processes responsible for the sensation of pain. Such procedures are the result of collaboration among surgeons, neurologists, anesthesiologists, cognitive scientists and others – an example of the importance of a multi-disciplinary approach to pain.