A long article, read the whole thing
here:
www.emedicine.com/PMR/topic68.htm
www.emedicine.com/PMR/topic68.htm
Quote:
Background: Low back pain (LBP) remains a common musculoskeletal complaint, with a reported lifetime incidence of 60-90%. Various structures have been incriminated as possible sources of chronic LBP, including the posterior longitudinal ligament, dorsal root ganglia, dura, annular fibers, muscles of the lumbar spine, and the facet joints.
In 1911, Goldwaith first implicated the facet joints as a source of LBP. In 1933, Ghormley described the facet syndrome, and, in 1941, Badgley endorsed the idea on the basis of pathomorphologic studies of the joint. Rees in 1972 and Shealy in 1974 accepted the notion and developed techniques in which the joint allegedly could be denervated to stop pain stemming from the facet joints.
In 1963, Hirsch injected normal saline into facet joints, demonstrating that facet joints can produce LBP. Systematic studies began in 1976 when Mooney and Robertson, and later McCall et al in 1979, used fluoroscopy to confirm this location of intra-articular lumbar facet joint injections of normal saline in asymptomatic volunteers. These injections of normal saline caused back and lower extremity pain. In addition, Mooney and Roberts documented relief of low back and lower extremity pain in these patients after injection of local anesthetic into the provoked facet joints. A 1989 study by Marks demonstrated similar findings in patients with chronic LBP.
In 1991, Kuslich et al probed facet joint capsules in patients undergoing lumbar decompression surgeries and found that pain could be induced. Many investigators developed and used techniques to diagnose facet joint pain using intra-articular joint blocks and medial branch nerve blocks, as well as ways to treat it with intra-articular steroids, surgical ablation, or radiofrequency (RF) denervation. Controversy continues regarding the true prevalence, most accurate diagnostic methods, and most efficacious treatment of symptomatic lumbar facet joints.
USA
Virginia
Australia
article
Mosken, filled with good info too. 
