Several cases have been reported recently in which symptoms suggestive of transient radicular irritation occurred following the use of hyperbaric 5% lignocaine for spinal anaesthesia. We report on three patients in whom we observed similar symptoms attributable to this kind of radicular irritation following uneventful spinal anaesthesia using isobaric 2% lignocaine. All three patients underwent minor gynaecological procedures and developed burning pains in the buttocks within 24 h of surgery. The long-term outcome was not clear for all the patients, but in at least one the pain disappeared.

Hampl, Schneider, Bont, Pargger, , , , , (1996). Transient radicular irritation after single subarachnoid injection of isobaric 2% lignocaine for spinal anaesthesia. Anaesthesia, 1996 Feb;51(2):178-81. https://www.ncbi.nlm.nih.gov/pubmed/8779378