This ppt will give you the basic knowledge about the peripheral nerves of lower limb, course and its innervations.

1. BY
HERMIZAN HALIHANAFIAH

2. Femoral nerve
Largest branch of lumbar plexus
Arises from ventral rami of posterior division of 2nd
, 3rd
and 4th
lumbar spinal nerves.
While still in abdomen, it will branch off to innervate iliacus
muscle.
Descend through psoas major fiber
Runs beneath inguinal ligament into the thigh.
And enter the femoral triangle
Divide into 2 divisions, anterior and posterior division.
Anterior division supplies sartorius and forms anterior
cutaneous nerve of the thigh

4. Lumbar Plexus

5. Femoral Nerve (Cont..)
Posterior division supplies quadriceps femoris and
also sends articular branch to the hip and knee joint.
Posterior division also give off the branches for the
saphenous nerve (cutaneous branch).
Saphenous nerve is the longest of the branches of the
femoral nerve.
Beginning below the inguinal ligament, passes
through the femoral triangle and go to the medial
side of the thigh .

6. Femoral Nerve (Cont..)
Passing behind the medial condyle of the femur and
tibia.
The descends along the medial side of the leg and lie
anterior to the medial malleolus.
Then passes too the medial side of the foot as far as
head of the 1st
metatarsal.
Branches of the saphenous nerve supply skin on the
anterior and medial side of the knee, leg and foot as
far as the base of the great toe.

7. Sum Up of the Femoral Nerve
From : posterior division of lumbar plexus
Root : L2, L3 and L4
Motor innervation : iliacus, sartorius, pectineus ,
quadriceps femoris (rectus femoris, vastus lateralis,
medialis and intermedius)
Cutaneous innervation :
Anterior cutaneous nerve of the thigh (anterior
femoral cutaneous) – supply skin at the anterior and
medial aspect of the thigh
Saphenous nerve – supply skin at the anteromedial
aspect of the knee, leg and foot (as far as base of the
big toe)

8. Obturator Nerve
Arises form ventral division of the 2nd
, 3rd
and 4th
lumbar spinal nerves (L2-L4)
Descend through psoas major muscles, cross the
medial border of pelvis brim and enter the obturator
foramen.
Branch off to muscular branches and cutaneous
branches at the thigh.

9. Obturator Nerve

10. Muscular branches supply adductor muscles of the
thigh.
Start with obturator externus, adductor brevis,
adductor longus, adductor magnus and gracilis
(sometimes pectineus).
Cutaneous branch – skin over upper medial aspect of
the thigh.

11. Sum Up of Obturator Nerve
From: anterior division of the lumbar plexus
Root value: anterior division of L2-L4
Motor innervations : adductor longus, adductor
brevis, adductor magnus, gracilis, obturator externus
and pectineus (rare)
Skin innervations : cutaneous nerve of obturator
nerve – supply skin at the superior medial aspect of
the thigh.

12. Sciatic Nerve Large nerve fiber in human beings
 Begin in lower back, runs through the buttock and
down to lower limb.
 Derived from anterior rami L4 – S3 spinal nerves.
 Leaves the pelvis to enter the gluteal region through
the greater sciatic foramen.
 Consist of 2 separate nerves in one sheath.
1. Tibial nerve
2. Common peroneal (fibular) nerve

13. Lumbosacral Plexus

14. Sciatic Nerve

15. Common peroneal nerve is formed by the upper 4
posterior division of the sacral plexus (L4-S2).
Tibial nerve is formed from all anterior divisions of
the sacral plexus (L4-S3).
Sciatic nerve leaves the pelvis through the greater
sciatic foramen, through the posterior of the femur
and terminate in the distal part (poplietal fossa) by
dividing into tibial and common peroneal nerves.

16. In the thigh, it supply the hamstring muscles
Rami from tibial trunk pass to the semitendinosus,
semimembranosus, long head of biceps and adductor
magnus.
Rami from common peroneal trunk supply short head
of biceps.
At the posterior knee joint, sciatic nerve divide into
tibial and common peroneal nerve.

17. Sciatic Nerve
Just posterior to knee joint,
sciatic nerve will branch off
to form medially tibial nerve
and laterally common
peroneal nerve.
Tibial nerve will running
posteriorly of the leg and
enter the plantar of the foot.
Common peroneal nerve
descends anteriorly of the
leg and enter the dorsum of
the foot.

18. Tibial Nerve
Medial terminal branch of the sciatic nerve.
After branch off from sciatic nerve at posterior knee
joint, tibial nerve will pass through the popliteal fossa.
In the popliteal fossa the nerve give off the branches
to the gastrocnemius, plantaris, popliteus and soleus.
Below the soleus muscles, the nerve lies near to the
tibia and supply tibialis posterior, flexor hallucis
longus and flexor digitorum longus.

19. For cutaneous branch, it will arise to the sural
nerve and supply the skin lateral side of the leg.
The nerve pass into the foot running posterior to
the medial malleolus.
Here it bound by the flexor retinaculum of the foot.
In the foot the tibial (sural nerve) divide into lateral
and medial plantar nerves.

20. Medial Plantar Nerve
Medial plantar nerve will supply
abductor hallucis, flexor
digitorum brevis, flexor hallucis
brevis and 1st
lumbricals.
Medial plantar nerve supply the
skin medial 2/3 plantar surface of
the foot. (medial side of the sole
and great toe and the adjacent
sides of the great, 2nd
, 3rd
and 4th
toes, and include the dorsal
surface of the distal phalanx and
nail bed)

21. Lateral Plantar NerveLateral plantar nerve supply remaining
muscles of foot not supply by medial
plantar nerve. (flexor digiti minimi
brevis,abductor digiti minimi, adductor
hallucis, lateral three lumbricals and
palmar and dorsal interossei.
For cutaneous sensation supply skin
lateral 1/3 palmar of the foot. (lateral side
of the sole and 5th
toes and to the
adjacent sides of the 4th
and 5th
toes,
including nailbeds and dorsum of the
distal phalanx.

22. Medial Calcaneal Nerve
Last branch of tibial nerve
is a medial calcaneal
nerve.
supply the skin of the heel
and medial side of the sole
of the foot.

24. Common Peroneal (Fibular) Nerve
Arises from posterior division of L4, L5, S1 and S2
spinal nerves.
After giving off branches from sciatic nerve at
posterior to the knee, descend obliquely on the lateral
side of the popliteal fossa to the head of fibula.
Lie between tendon biceps femoris and lateral head
of gastroc muscles and winds around neck of fibula.

25. Continue…
Then it branch to the superficial and deep peroneal
nerves.
Superficial peroneal nerves lies lateral aspect of the
fibula and supplies muscles in the lateral
compartment of the leg. (fibularis brevis and longus).
Supply skin distal 1/3 anterior leg and greater part
dorsum surface of the foot.

26. Continue…
Deep peroneal nerve lies anterior aspect of the leg.
Supplies muscles anterior compartment of the leg
and dorsal foot muscle (extensor digitorum brevis).
For cutaneous sensation supply skin between great
toe and 2nd
toe (web)

29. Clinical Condition

30. Injury to Tibial Nerve