A caudal epidural injection is used for patients with nerve type (neuropathic) pain in the lower limbs. When nerves are irritated by compression in the spine they can produce pain in the lower limbs. Most often patients complain of continuous or spontaneous pain on the outer or inner aspect of their leg, calf and foot.
This procedure involves the injection of local anaesthetic and steroid into the epidural space. The epidural injection is thought to act through a variety of mechanisms. It is thought that the local anaesthetic and steroid alter pain signals and decrease inflammation in the spine. The volume injected is also thought to ‘free up’ some of the nerve endings and decrease entrapment.
On average most patients get three to nine months relief of pain with most patients getting on average six months of relief. Some patients however get minimal relief from the procedure. This procedure should only ideally be carried out once in six months. In some patients it may be carried out over shorter periods.
This procedure is performed as a day patient. You will be prepared for theatre and placed in a theatre gown. Once you are on the operating table, the anaesthetist will place a cannulae in your arm and sedative drugs will be administered.
The procedure is performed under sterile conditions. The area around your sacrum (tail bone) is infiltrated with local anaesthetic and a needle is introduced into the epidural space. The epidural space is a loose space surrounding the spinal cord. Once this place is found some dye is introduced into this area to confirm the position of the needle. Local anaesthetic and steroid is then injected into the area. Some patients describe an unpleasant feeling of fullness in the pelvis and back when the steroid and anaesthetic is injected. The correct positioning of the needle is done with x-ray guidance.