Sciatica:

a) Anatomy –

It is the thickest nerve in the body. It is the largest branch of the sacral plexus. It begins in the pelvis and terminates at the superior angle of the popliteal fossa by dividing into tibial ( medial) and peroneal nerves.

Its root value is L4 L5 S1 S2 ans S3.

b) Definition : – Shooting  pain   along the cutaneous distribution of sciatic nerve and its terminal branches chiefly the common paroneal is known as sciatica. Pain usually begins in the gluteal region and radiates along the back of thigh and lateral side of the leg , to the dorsum of the foot.

c) Medicine – The semimembranosus bursa may get inflamed, the condition called semimembranosus bursitis.The sciatic nerve may be  injured by penetrating wound, dislocation of the hip. This result in loss of movement below the knee and foot drop; sensory loss on the back of the thigh.

1. 1. Motor loss includes loss of hamstrings muscle, dorsiflexion, plantar flexors, and muscle of soles.
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3. 1. Diagnosis technique : Straight leg raising test: Testing the hamstring muscles, . The affected leg is extended at both hip and knee joint . Then it is raised by by holding the foot. As the nerve is stretched , it cause severe pain.