Human has 26 facet joints on each side, which are synovial joints like a knee joint. These facet joints protect the motion segment from anterior shear forces, excessive rotation and flexion. Facet joints appear to have little influence on the range of side bending (lateral flexion). These functions can be disrupted by degeneration, dislocation, fracture, injury, instability from trauma and osteoarthritis. In the thoracic spine, the facet joints function to restrain the amount of flexion and anterior translation of the corresponding vertebral segment and function to facilitate rotation. Cavitation of the synovial fluid within the facet joints is responsible for the popping sound (crepitus) associated with manual spinal manipulation, commonly referred to as “craking the back”. It will damage facet your joint and should not be done.
Wear and tear of age due to mechanical forces of the facet joint cause pain which is called facet joint osteoarthritis.These facet joints get its nerve supply from the corosponding root. The degenerative process of the intervertebral disc also causes a change in mechanical weight distribution in facet joints and that will lead to aggravation in facet joint arthritis.
Day to day activity will involve bending, twisting and lifting weights which cause aggravation of facet joint pain. To make the diagnosis of pain due to disc disease or facet joint arthritis modality of the diagnostic tool is a facet block or discogram .facet joint arthritis may mimic a pinch nerve pain which is radiating to the extremity.
Treatment depends on the duration and severity of facet pain. Facet pain may respond well to a short course of pain medication, therapy and facet joint injections. Facet pain refractory to these treatments usually requires rhizotomy to effectively relieve painful symptoms. Rhizotomy is the destruction of the small nerve to the facet joint. Facet medial branch rhizotomy is the most effective procedure designed to treat this condition and should be combined with therapy to optimize results and durability.
Refractory patients with rhizotomy will require surgery called facetectomy and fusion.