Epidural steroid injections are most commonly used in situations of radicular pain, which is a radiating pain that is transmitted away from the spine by an irritated spinal nerve. Irritation of a spinal nerve in the low back ( lumbar radiculopathy ), such as from lumbar spinal stenosis , cervical spinal stenosis, herniated disc , and foraminal encroachment, causes back pain that goes down the leg. Epidural injection is also used as a minimally invasive procedure to treat nerve compression in the neck (cervical spine), referred to as cervical radiculopathy , which causes pain.
Distal traction may be applied to the great toe to open the joint space. The needle is inserted on the dorsomedial or dorsolateral surface ( Figure 6 ) . The needle should be angled 60 to 70 degrees to the plane of the foot and pointed distally to match the slope of the joint. The joint space is not deep below the skin surface. The physician should aspirate before injecting; the injectable agent should flow without major resistance when the needle is positioned properly in the joint space. Follow-up care is the same as that previously described.