 The nerve supply - medial branch and dorsal ramus have been the target for RF interventions to relieve facet joint pain. Anatomical studies in 1980s found that facet joint has a dual innervation - for instance, the L4-5 facet joint derives its innervation from the medial branches of dorsal rami of L3 and L4. The medial branches of L1-4 and the posterior primary ramus of L5 have a relatively fixed anatomical course, thereby rendering themselves good targets for interventions. This forms the basis of targeting two nerves to denervate one facet joint. The success rate of RF denervation varies from 50 to 90 .9, 10 The varied success rate is often attributed to single diagnostic blocks and procedural variations. But anatomical variation is not often considered. A recent study has showed that there is significant variation in the individual nerve supply to facet joints which may add to the false -negatives of diagnostic blocks and inadequate pain relief from radiofrequency denervation. One way of improving the success rate is to reproduce the pain by electrical stimulation prior to RF treatment. 