ABSTRACT
Sensory nerve blocks are widely used in chronic pain management for diagnostic and therapeutic purposes. Local anaesthetic agents and neurolytic substances such as phenol, alcohol, or glycerol can be used, depending on the indication. Radiofrequency (heating) or cryotherapy (freezing) probes can be used to cause a lesion in a nerve after precise localization with X-ray and nerve stimulation. Drugs with differing mechanisms of action, such as depot steroids, clonidine and opioids can be added to local anaesthetic. Historically, nerve block procedures were the cornerstone of pain clinic practice: their role has changed as more techniques for medical management are available and as pain relief is seen as part of a strategy of rehabilitation.
