Why is my leg vibrating after injections in my back?

Nerve stimulation: It is most likely the nerves that emanate from your spinal cord, that innervate your legs, are being stimulated from the injection. If it persists, call your dr for an evaluation. Good luck to you.

Typical Nerve: Nerves do all sorts of things when irritated so it is common to feel the vibration sensation. Usually this will go away on its own. If you are worried then see your doctor for further evaluation.