- Sciatic nerve
The sciatic nerve, also known as the ischiadic nerve, begins at the lower back, derived from spinal nerves L4 through S3. It supplies most of the skin of the leg and he muscles of the lower limb.
The sciatic nerve passes out of the pelvis through the greater sciatic foramen below the piriformis muscle, and extends downward between the greater trochanter of the emur and the ischial tuberosity.
Patient should lie in the Sims position with the affected side uppermost, and the upper leg flexed.
1. Locate the upper extremity of the greater trochanter and the posterior superior iliac spine.
2. Draw an ilio-trochanter line upon the skin. At its midpoint, draw a perpendicular downward for a distance of 3 cm to locate the point at which the needle is to be inserted.
3. At the site, insert a 3½-inch, 25-gauge needle slowly perpendicular to the skin until paresthesia is elicited, usually at a depth of 6 to 8 cm.
a. The depth will depend on the patient’s weight.
b. If the nerve is not contacted as evidenced by lack of paresthesias, withdraw the needle and gently reintroduce until the nerve is located.
4. Once paresthesia has been elicited, withdraw the needle out 1mm and slowly inject 10 to 20 cc of SARAPIn® depending on severity of the pain
a. Injections may be repeated daily or every other day, according to the response, for a total of up to 10 injections.