There are many causes for chronic abdominal pain. Chronic abdominal pain needs to be evaluated first by a health care provider, preferably a gastroenterologist or GI specialist. Treatable conditions need to be addressed medically or surgically. If the cause of chronic abdominal pain remains unknown or not otherwise amenable to traditional medical or surgical approaches, then consultation with a Pain Medicine specialist is appropriate. Chronic pain in the abdomen may arise from the spine, the abdominal wall, or the internal (visceral) organs.
Pain arising from the spine may be related to compression of nerves that exit the spinal cord (spinal stenosis or disc herniation) or could be related to a vertebral compression fracture.
Pain may also arise from the abdominal wall due to compression of perforating nerves that travel through this area. Other nerves may be injured as a result of trauma or surgery involving the abdominal wall. These include the genifoemoral nerve and the ilioinguinal/iliohypogastric nerves resulting in genitofemoral neuralgia and ilioinguinal neuralgia, respectively. In addition, the muscles in the abdominal wall may be the cause of myofascial pain usually associated with the presence of trigger points. This is sometimes evident around abdominal surgical scars.
The internal organs of the abdominal cavity consist of the pancreas, liver, spleen, small intestine including the appendix, the large intestine and the kidneys. In addition pelvic organs may also be the cause of abdominal pain including the ovaries, uterus and testes. Any of the internal organs can result in chronic visceral abdominal pain, usually as a result of inflammation, infection or tumor. Chronic pancreatitis, which occurs secondary to repeated insults to the pancreas by drugs, alcohol or gallstones, can result in visceral pain.
Treatment of chronic abdominal pain differs based on the origin of pain. The ultimate goal of any therapy is always functional rehabilitation, i.e. going back to doing whatever one was able to do prior to the onset of pain. Interventions used in the management of chronic abdominal pain include diagnostic blocks and therapeutic interventions. Examples of diagnostic blocks used in the treatment of abdominal pain include diagnostic peripheral nerve blocks and differential epidural blockade.
Examples of therapeutic interventions in the management of abdominal pain include peripheral nerve radiofrequency ablation or cryoablation, epidural steroid injections, facet nerve radiofrequency ablation. Therapeutic interventions aimed at visceral abdominal pain include celiac plexus block or splanchnic nerve blocks for upper abdominal visceral pain and superior hypogastric block for lower abdominal/pelvic pain of visceral origin. Other interventions may include spinal cord stimulation or spinal infusion pumps in selected cases. Physical therapy and medications are often prescribed in conjunction with the therapeutic procedures to assist in the rehabilitation process.