Chronic pain due to damaged nerves is called neuropathic pain and is common. Some people postulate that neuropathic pain, particularly reflex sympathetic dystrophy and causalgia, is caused by the sympathetic nervous system (a part of the autonomic nervous system that is involved in the response to stress and in the control of the functioning of many internal organs). Sympathectomy is a destructive procedure that interrupts the sympathetic nervous system. Chemical sympathectomies use alcohol or phenol injections to destroy sympathetic nervous tissue (the so-called "sympathetic chain" of nerve ganglia). Surgical ablation can be performed by open removal or electrocoagulation (destruction of tissue with high-frequency electrical current) of the sympathetic chain, or minimally invasive procedures using thermal or laser interruption. Nerve regeneration commonly occurs following both surgical of chemical ablation, but may take longer with surgical ablation.
This systematic review found only one small study (20 participants) of good methodological quality, which reported no significant difference between surgical and chemical sympathectomy for relieving neuropathic pain. Potentially serious complications of sympathectomy are well documented in the literature, and one (neuralgia) occurred in this study.
The practice of sympathectomy for treating neuropathic pain is based on very weak evidence. Furthermore, complications of the procedure may be significant.