A comparison of analgesic efficacy and safety of clonidine and methylprednisolone as additives to 0.25% ropivacaine in stellate ganglion block for the treatment of complex regional pain syndrome: a prospective randomised single blind study.

The use of additives, both methylprednisolone and clonidine, is safe and effective for the SGB in CRPS. The significantly better improvement in joint mobility with methylprednisolone suggests that it should be considered promising as an additive to local anaesthetics when joint mobility is the concern.