Sciatic Nerve

[ Home ] [ Up ]

Pages Below:

Tibial Nerve
Common Peroneal Nerve

• From L4,L5,S1,S2,S3

Motor Supply

• semitendinosus
• biceps femoris
• semimembranosus
• adductor magnus

Then splits into tibial and common peroneal nerves

Sensory Supply

Path

1. emerges from pelvis below piriformis
2. curves laterally and downward through gluteal region
3. starts midway between 
   • posterior superior iliac spine
   • ischial tuberosity
4. later midway between
   • tip of greater trochanter
   • ischial tuberosity
5. passes downward in midline on posterior aspect of thigh
6. passes deep to biceps femoris
7. divides into tibial and common peroneal nerves about half way down thigh (variable)

Common Pathology

• misplaced injection in the buttocks
• hip replacement surgery
• sciatica

Motor

• hamstrings paralysed
• weak flexion of knee possible
  • sratorius and gracilis spared
• all muscles below knee paralysed
  • footdrop

Sensory

• loss of sensation below knee
  • except medial side lower leg (saphenous nerve)

[ Home ] [ Up ]