Hello everybody,hope you are all doing well and i am too.we finished upperlimb and its clinical aspects and you can go through them.now we are entering into lower limb.lower limb is somewhat easy and not complicated to learn as compared to upperlimb.so lets learn about lower limb.

In upper limb we learned about brachial plexus and its divisions like that how they are going to supply.like that in lower limb also we have plexus named as "Lumbosacral plexus".it looks like complicated but we can learneasily by schematic diagram.

LUMBOSACRAL PLEXUS

L1,L2,L3,L4,L5,S1,S2,S3 spinal nerves contribute for formation of lumbo sacral plexus

Lumbosacral plexus has only divisions-

• Anterior division
• Posterior division

You can see in diagram,that anterior division has two nerves - 1) Obturator nerve and 2) Tibial nerve

Posterior division has two nerves - 1) Femoral nerve and 2) Common peroneal nerve/Fibular nerve

Root values -

• Obturator nerve - L2,L3,L4
• Femoral nerve - L2,L3,L4
• Tibial nerve - L4,L5,S1,S2,S3
• Common peroneal nerve - L4,L5,S1,S2

Common peroneal nerve/fibular nerve is divided into deep peronal nerve and superficial peroneal nerve

• NERVUS FURCALIS:- L4 is referred to as nervus furcalis because it contributes to all the neeves of lumbosacral plexus

SCIATIC NERVE

sciatic nerve is not a separate nerve but it is a sheath enclosing the tibial nerve and common peroneal nerve.so its root value is L4 to S3.

Image source

Sciatic nerve enters into gluteal region through greater sciatic foramen and it descends down into the posterior compartment of thigh and enters into popliteal fossa.in the upper part of popliteal fossa,it divides into tibial nerve(medial side) and common peroneal nerve(lateral side)

We divided upperlimb into three parts like arm,forearm and hand.in the same manner here in lower limb also we divide the lowerlimb into thigh,leg and foot

Thigh is divided into 3 compartments - Anterior,Posterior and medial/adductors

Leg is divided into 3 compartments - Anterior,Posterior and lateral

Foot has no compartments but it is arranged in 4 layers.

MAJOR NERVES

Now we have to know which compartment is supplied by which nerve

In thigh region

• Anterior compartment by Femoral nerve
• Posterior compartment by Tibial nerve
• Medial compartment by Obturator neeve

In Leg region

• Anterior compartment by Deep peroneal nerve
• Posterior compartment by Tibial nerve
• Lateral compartment by Superfical peroneal nerve

In Foot region

• 4 layers are supplied by lateral and medial plantar nerves which are branches of tibial nerve.

If we learn about these things in the perfect manner then we are going to learn each major nerve and its course and its supply in detail in upcoming posts easily.so stay tuned.

Thank you,
With regards