The statistical distribution of members of a population around the population mean. In a gaussian distribution, 68.2% of values fall within Â± 1 standard deviation (SD); 95.4% fall within Â± 2 SD of the mean; and 99.7% fall within Â± 3 SD of the mean. Synonym(s): bell-shaped curve, normal distribution.
Located on the bony extensions of the vertebrae, the surfaces of the facet joints fit together like a three-dimensional puzzle. In the spaces between vertebrae run the nerve rootsâexits off the spinal cord's information highway.
Facet joint injection in the lumbar spine. Facet joint injections can also be done for both diagnostic and therapeutic reasons. These types of injections are often used when pain is caused by degenerative/arthritic conditions or injury. They are used to treat neck, middle back, or low back pain.