title: Anatomical description of the facet joint innervation and its implication in the treatment of recurrent back pain.
abstract: OBJECTIVE
  Many techniques are used in the back pain treatment, standing out the facet denervation as a therapeutic option for pain that originates in the facet joints. It's known that the facet joint is an abundant area of nocireceptor innervation, although the distribution and the location of the involved branches have not being well demonstrated. A good comprehension about the affected innervation is very important to get an effective treatment. Purpose of study was to describe innervation of the lumbar facet joints, potentially used in the diagnosis and treatment of painful pictures of the lumbar region by facet syndrome.
  
  
  METHODS
  anatomical study of nerve roots distribution of the facet joint 3 human corpses. The determination of the neurotomy s point was carried out by direct visualization and the radiological study in human parts.
  
  
  METHODS
  Three anatomical pieces of the human lumbar spine were dissected. In those 3 pieces, the facet joint innervation distribution was studied thoroughly using surgical microscope and microsurgical technique. In one of the pieces the needles positioning was first made to test through the radiological study the possible application of the precise denervation in low back pain treatment.
  
  
  RESULTS
  The L1 to L4 segments, each dorsal branch of root emits a medial branch that emerges from intertransversal ligament. This branch crosses the superior margin of the medial termination of transverse process, passing through the root of the superior articulate process. Each branch innerves the anterior region of the inferior facet and the inferior portion of articulation which one spins around. The L5 dorsal branch was larger than the superior branches. It emerges dorsally and in the inferior region on top of the sacrum wing. This nerve is in the bone fissure of the junction between the wing and the posterior region of the sacrum articular process. Near the inferior portion of the articular process, the nerve ramifies itself in lateral and medial branch. The medial branch comes back around the inferior portion of the lumbar-sacrum articulation that it innervates.
  
  
  CONCLUSIONS
  We didn't note great variations in the anatomy from L1 do L4. The L5 segment has a different distribution of the branches that should be considered when we do a percutaneous denervation procedure. The approach of the needle must touch the transverse process and feels the resistance of the articular joint . The determination of the neurotomy s point tends to become more precise denervation procedure.
authors.affiliation: Department of Neurosurgery, Federal University, Sao Paulo, Brazil.
authors.forename: M
authors.initials: M
authors.lastname: Masini
authors.forename: W S
authors.initials: WS
authors.lastname: Paiva
authors.forename: A S
authors.initials: AS
authors.lastname: Araújo
mesh_terms: D001416:Back Pain / Q000209:etiology*; D006801:Humans; D008161:Lumbosacral Region / Q000294:innervation*; D013127:Spinal Nerves / Q000033:anatomy & histology*; D021801:Zygapophyseal Joint / Q000294:innervation*