Local anaesthetic sympathetic blockade (LASB) is a common treatment for complex regional pain syndrome (CRPS). It involves blocking the activity of sympathetic nerves in the spine through the injection of a local anaesthetic drug. This updated review sought to identify the available evidence regarding whether LASB is effective at reducing pain in CRPS, how long any pain relief might last, and whether LASB is safe.
We found a small number of small trials, all of which may be at risk of bias. We did not find evidence that LASB was better than placebo in reducing pain, or that it provided additional pain relief when added to rehabilitation. While a number of small studies compared LASB to other treatments, most did not find that LASB was better than any other intervention. Only five studies reported on adverse events. These studies reported only minor side effects but since most studies did not report this information we can draw no firm conclusions about the safety of LASB.
Overall, while the evidence is very limited and precludes the drawing of strong conclusions, the existing evidence does not provide support for the efficacy of LASB in managing people with CRPS.