This document provides information about the sciatic nerve and muscles it innervates. It originates from the ischial tuberosity and inserts into the tibia and fibula bones of the leg. It is supplied by the tibial division of the sciatic nerve. The muscles it innervates allow for flexion of the knee and extension of the hip. These muscles include the semitendinosus, semimembranosus, and biceps femoris. Compression of the sciatic nerve can occur against the femur or from conditions like lumbar disc prolapse and can result in shooting pain along the nerve's cutaneous distribution.

6. Origin – Ischial Tuberosity
Insertion – Bones of leg Tibia / Fibula
Supplied by Tibial division of Sciatic Nv.
Flexors of knee and extensors of Hip
Semitendinosus
Semimenranosus
Biceps Femoris
Ischial part of Adductor Magnus

13. BACK OF
LEFT THIGH

14. Biceps Femoris
iLio tibial
tract
Rt. Knee lat. Side

17. SACRAL PLEXUS – SCIATIC NERVE
Dorsal divisions
Ventral divisions
L4
L5
S1
S2
S3
Lumbosacral trunk
Superior gluteal
Inferior gluteal
Sciatic nerve
Common peroneal part
Tibial part
Q.Femoris / Inf.Gem.
Obt.Int.
Post.cut.nr.of thigh.
Piriformis

22. Compression of nerve against femur
- Unusual stretching after sitting for long time
“ Sleeping foot”
- Shooting pain along cutaneous distribution of
sciatic nerve – begins in gluteal region; radiates
to back of thigh, lateral side of leg, dorsum of foot.
- Compression of sciatic nerve by
Osteoarhtitis, Lumbar disc prolapse,
spondylolisthiasis, Fibrositis, Neuritis etc.
penetrating wounds, dislocation / fracture
of pelvis – foot drop and sensory loss.

24. VERTICAL LINE
HORIZONTAL LINE
HIGHEST P[OINT OF
ILIAC CREST
SAFE INJECTION
REGION
SCIATIC NERVE
ISCHIAL TUBEROSITY