Cortisone-injections are applied to the muscle or are administered inside the joint. Usually there is no official preparation for the procedure, although you may be asked to stop taking blood-thinning medications for a few days before the procedure, to reduce your chances of bleeding.
A cortisone shot can be performed right in your doctor's office. Your doctor will probably arrange you so that the muscles near the spine can be as relaxed as possible. Your skin may be numbed, but the injection itself may still be uncomfortable. You may feel, for example, a sharp pain or muscle twitching or your doctor may need to adjust the needle position and inject medicine into the area from several different angles.
The anesthetic in the shot wears off within a few hours, and it may take a few days before the corticosteroid works. In the meantime, the area near the cortisone infection may be a little sore and swollen., which you can relieve with an ice pack.