Like any joint in the body, facet joints can cause pain if they are irritated or inflamed. The facet joint block is a procedure where a local anesthetic medication (such as lidocaine or Novocain) is injected into the facet joint. This same type of medication is used by a dentist to numb your jaw, or a doctor to sew up a laceration. The lidocaine actually numbs the area around the facet joint. If all your pain goes away, the doctor can assume that the facet joint is a problem. Facet joints are paired joints on the side of the midline at each level of the spine.

The facet block is a diagnostic test to localize the source of your pain by
determining if your pain responds to the injection of medication. Alternatively,
this procedure is used to treat symptoms arising from facet joint arthritis.

An epidural is an injection that delivers steroids directly into the epidural space in the spine. Sometimes a flushing solution (either lidocaine or normal saline) is also used to help "flush out" inflammatory proteins from around the area that may be the source of pain.

The epidural space is the space between the dura mater (a membrane) and the vertebral wall and is filled with fat and small blood vessels. It is located just outside the dural sac. The dural sac surrounds the nerve roots and cerebrospinal fluid (the fluid that the nerve roots are bathed in).

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