Gluteal Sciatic Nerve Block
The sciatic nerve is commonly blocked at the gluteal region (Labat approach) if anesthesia of the thigh and knee is required in addition to that of the lower leg.
One of its more useful applications is for surgical anesthesia for above knee amputation.
It is commonly necessary to combine this block with a femoral nerve block (single shot or continuous) for analgesia after knee arthroplasty.
For ankle or foot surgery it may also need to be used in combination with femoral nerve blockade.
Saphenous nerve blockade will suffice if the goal is anesthesia of the skin of the medial surface of the ankle and foot. However, blockade of the entire femoral nerve will allow use of a tourniquet.
The gluteal approach may be preferred to a more distal popliteal approach for blockade of the sciatic nerve if a thigh tourniquet is to be used.
The sciatic nerve is commonly blocked at the gluteal region (Labat approach) if anesthesia of the thigh and knee is required in addition to that of the lower leg.
One of its more useful applications is for surgical anesthesia for above knee amputation.
It is commonly necessary to combine this block with a femoral nerve block (single shot or continuous) for analgesia after knee arthroplasty.
For ankle or foot surgery it may also need to be used in combination with femoral nerve blockade.
Saphenous nerve blockade will suffice if the goal is anesthesia of the skin of the medial surface of the ankle and foot. However, blockade of the entire femoral nerve will allow use of a tourniquet.
The gluteal approach may be preferred to a more distal popliteal approach for blockade of the sciatic nerve if a thigh tourniquet is to be used.
Anatomy
The sciatic nerve (L4, L5, S1–S3) is part of the sacral plexus; about 2 cm broad at its origin in the adult and a flattened oval in cross-section, the sciatic nerve is the broadest and largest peripheral nerve in the human body.
Proximally, the nerve lies deep to the gluteus maximus resting first on the posterior ischial surface and then coursing inferiorly posterior to the obturator internus, gamelli, and quadratus femoris muscles to enter into the back of the thigh where it divides.
The nerve generally divides into the tibial nerve medially and the common peroneal nerve laterally near the apex of the popliteal fossa (approximately two thirds of the way down the thigh; however, its division is variable and can occur at a more proximal location, anywhere between the piriformis muscle and the popliteal fossa, or occasionally at a more distal location.
The nerve has its own artery, the artery to the sciatic nerve or the arteria comitans (from the inferior gluteal artery), which lies on the posterior aspect of the nerve and is contained within the fibrous sheath surrounding the nerve.
The sciatic nerve (L4, L5, S1–S3) is part of the sacral plexus; about 2 cm broad at its origin in the adult and a flattened oval in cross-section, the sciatic nerve is the broadest and largest peripheral nerve in the human body.
Proximally, the nerve lies deep to the gluteus maximus resting first on the posterior ischial surface and then coursing inferiorly posterior to the obturator internus, gamelli, and quadratus femoris muscles to enter into the back of the thigh where it divides.
The nerve generally divides into the tibial nerve medially and the common peroneal nerve laterally near the apex of the popliteal fossa (approximately two thirds of the way down the thigh; however, its division is variable and can occur at a more proximal location, anywhere between the piriformis muscle and the popliteal fossa, or occasionally at a more distal location.
The nerve has its own artery, the artery to the sciatic nerve or the arteria comitans (from the inferior gluteal artery), which lies on the posterior aspect of the nerve and is contained within the fibrous sheath surrounding the nerve.
