Sacral Plexus Flashcards
ventral rami
L4 - S4
SUPERIOR GLUTEAL
L4,5,S1 Exits greater sciatic foramen, above piriformis 1. Gluteus medius 2. gluteus minimus 3. tensor fascia lata
INFERIOR GLUTEAL
L5,S1,S2
Exits greater sciatic foramen inferior to piriformis
1. gluteus maximus
TIBIAL
L4 – S3
Travels with the Common fibular N. Exits greater sciatic foramen inferior to piriformis & passes into the thigh midway between the ischial tuberosity & greater trochanter. Descends centrally through posterior compartment of thigh, popliteal fossa & posterior compartment of leg to ‘tarsal tunnel’ behind medial malleolus. Branches in plantar aspect of foot into medial & lateral plantar nerves.
Tibial muscles
- long head biceps femoris
- semimembranosus
- semitendinosus
- posterior compartment of the leg
- All the muscles on the plantar aspect via the medial & lateral plantar nerves
COMMON FIBULAR
L4 - S2
Travels with biceps femoris tendon then passes around neck of fibula and into lateral compartment of leg between attachment of fibularis longus to head & shaft of fibula.
1. Short head biceps femoris
- SUPERFICIAL FIBULAR
Branch of common fibular. Descends in lateral compartment deep to FL & continues, anterior to lateral malleolus, onto dorsum of foot
- Fibularis longus
- Fibularis brevis
- DEEP FIBULAR
Branch of common fibular. Descends in anterior compartment deep to EDL & continues, between tendons of TA & EHL with dorsalis pedis artery, onto dorsum of foot to 1st web space.
- TA
- EDL
- EHL
- FIB. TERTIUS
- EDB
- EHB
Direct branches from
Sacral plexus
- Piriformis
- Obturator internus
- Quadratus femoris
- Superior/inferior gemelli
PUDENDAL
Exits via greater sciatic foramen, travels over sacrospinous/UNDER SACROTUBEROUS ligament then through lesser sciatic foramen
UROGENITAL DIAPHRAGM
Post. Fem. cutaneous
Medial to sciatic n
Sensory
Tarsak tunnel
Tibialis posterior tendon Flexor digitorum longus tendon Posterior tibial artery Posterior tibial vein Tibial nerve Flexor hallucis longus tendon
