Nerve Of The Leg Flashcards
What is the origin of the Lateral Femoral Cutaneous Nerve?
It arises from the dorsal (posterior) divisions of L2 and L3.
Where does the Lateral Femoral Cutaneous Nerve emerge from?
It emerges from the lateral border of the psoas major.
What muscle does the Lateral Femoral Cutaneous Nerve cross obliquely?
Iliacus muscle.
What ligament does the Lateral Femoral Cutaneous Nerve run under?
Inguinal ligament.
Into what two branches does the Lateral Femoral Cutaneous Nerve divide in the thigh?
Anterior branch and posterior branch.
How far below the inguinal ligament does the anterior branch of the Lateral Femoral Cutaneous Nerve become superficial?
About 10 cm.
What areas does the anterior branch of the Lateral Femoral Cutaneous Nerve supply?
Skin of the anterior and lateral parts of the thigh, extending to the knee.
What does the posterior branch of the Lateral Femoral Cutaneous Nerve do?
It pierces the fascia late and subdivides into filaments supplying the skin.
What surfaces of the thigh does the posterior branch of the Lateral Femoral Cutaneous Nerve supply?
Lateral and posterior surfaces of the thigh.
What is the range of the area supplied by the posterior branch of the Lateral Femoral Cutaneous Nerve?
From the greater trochanter at the hip to the middle of the thigh.
From which spinal levels does the femoral nerve arise?
L2-4
What muscles does the femoral nerve descend through?
Psoas major
What ligament does the femoral nerve pass beneath to enter the femoral triangle?
Inguinal ligament
Into how many divisions does the femoral nerve split in the femoral triangle?
Two divisions
What are the two divisions of the femoral nerve?
- Anterior division
- Posterior division
What types of branches does the anterior division of the femoral nerve give off?
- Anterior cutaneous branches
- Muscular branches
Which two nerves are included in the anterior cutaneous branches of the femoral nerve?
- Intermediate cutaneous nerve
- Medial cutaneous nerve
What muscle does the nerve to pectineus supply?
Pectineus
Which nerve arises together with the intermediate cutaneous nerve?
Nerve to sartorius
What parts of the leg does the muscular branches of the femoral nerve supply?
Four parts of the quadriceps compartment
What is the largest cutaneous branch of the femoral nerve?
Saphenous nerve
Where does the saphenous nerve lie in relation to the femoral artery?
In front of the femoral artery
What canal does the saphenous nerve follow as it travels down the leg?
Adductor canal (sub-sartorial canal)
The saphenous nerve extends as far as which anatomical landmark?
Adductor foramen
What is the primary function of the Femoral Nerve?
Motor and sensory innervation to the anterior thigh and part of the leg
The Femoral Nerve is crucial for knee extension and sensory perception in specific areas.
Describe the pathway of the Femoral Nerve.
Passes along the medial side of the knee, pierces fascia late, descends behind the medial border of the tibia, divides into two branches in the lower third of the leg
The branches include one that ends at the ankle and another that supplies the medial side of the foot.
What are the two branches of the Femoral Nerve at the lower third of the leg?
- One continues along the margin of the tibia to the ankle
- The other passes in front of the ankle to the medial side of the foot
The second branch communicates with the medial branch of the superficial peroneal nerve.
What is the origin of the Obturator Nerve?
Formed from the anterior branches of L2-4
The Obturator Nerve arises from the lumbar plexus.
What muscles does the Obturator Nerve innervate?
- External obturator
- Adductor longus
- Adductor brevis
- Adductor magnus
- Gracilis
These muscles are primarily responsible for adduction of the thigh.
What is the sensory function of the Obturator Nerve?
Sensory innervation of the skin of the medial aspect of the thigh
This provides sensation in the inner thigh region.
Fill in the blank: The Femoral Nerve becomes subcutaneous at the point where it pierces the _______.
fascia late
This is a critical point in the nerve’s pathway.
True or False: The Obturator Nerve passes through the obturator canal to enter the thigh.
True
This is an essential step in the nerve’s journey to innervate the thigh.
What does the sciatic nerve supply?
Almost all of the skin of the leg, the muscles of the back of the thigh, and those of the leg and foot.
The sciatic nerve plays a crucial role in lower limb functionality.
From which spinal nerves is the sciatic nerve derived?
L4-5 and S1-S3.
These spinal nerves are part of the lumbosacral plexus.
What types of fibers does the sciatic nerve contain?
Fibers from both the anterior and posterior divisions of the lumbosacral plexus.
This composition allows the nerve to serve various muscle and skin functions.
Where do the articular branches of the sciatic nerve arise from?
The upper part of the nerve.
These branches supply the hip joint.
Which muscles are innervated by the muscular branches of the sciatic nerve?
- Biceps femoris
- Semitendinosus
- Semimembranosus
- Adductor magnus
These muscles are primarily located in the posterior compartment of the thigh.
From which part of the sciatic nerve does the nerve to the short head of the biceps femoris come?
The common peroneal part.
This is in contrast to the other muscles supplied by the tibial part.
What does the muscular branch of the sciatic nerve eventually give off?
The tibial nerve and common peroneal nerve.
These nerves innervate the muscles of the leg.
Which nerve innervates all muscles of the foot except the extensor digitorum brevis?
The tibial nerve.
The extensor digitorum brevis is innervated by the peroneal nerve.
What is the tibial nerve?
The medial branch of the sciatic nerve
The tibial nerve is responsible for innervating various muscles in the leg and foot.
Where does the tibial nerve pass through?
The popliteal fossa
The nerve passes below the arch of the soleus muscle.
Which muscles does the tibial nerve give branches to in the popliteal fossa?
- Gastrocnemius
- Popliteus
- Soleus
- Plantaris
These muscles are involved in movements of the lower leg and foot.
What type of branches does the tibial nerve provide to the knee joint?
Articular branches
These branches are important for the sensory innervation of the knee joint.
What is the sural nerve?
A cutaneous branch of the tibial nerve that runs down the lateral side of the leg
The sural nerve is formed by contributions from the common fibular nerve.
Where does the sural nerve supply sensation?
The lateral side of the foot
It is important for sensory functions in that area.
Which muscles are supplied by the tibial nerve in the deep flexor compartment?
- Tibialis posterior
- Flexor digitorum longus
- Flexor hallucis longus
These muscles are crucial for foot flexion and movement.
What anatomical landmark does the tibial nerve pass behind as it enters the foot?
The medial malleolus
This is a prominent bony structure on the inner side of the ankle.
What structure does the tibial nerve pass under when entering the foot?
The flexor retinaculum
This structure helps to hold tendons in place during foot movement.
Into what two branches does the tibial nerve divide as it enters the plantar aspect of the foot?
- Medial plantar nerve
- Lateral plantar nerve
These branches provide innervation to different parts of the foot.
What is the Medial Plantar Nerve also known as?
Internal Plantar Nerve
It is the larger of the two terminal divisions of the tibial nerve.
Where does the Medial Plantar Nerve pass under?
Abductor hallucis
It appears between the Abductor hallucis and the Flexor digitorum brevis.
What does the Medial Plantar Nerve give off?
A digital plantar nerve
It finally divides opposite the bases of the metatarsals into three common digital plantar nerves.
What types of branches does the Medial Plantar Nerve have?
- Cutaneous
- Muscular
- Articular
Each branch serves different functions in the foot.
What do the cutaneous branches of the Medial Plantar Nerve supply?
The skin on the plantar aspect of the foot
They pierce the plantar aponeurosis between Abductor hallucis and Flexor digitorum brevis.
Which muscles are supplied by the muscular branches of the Medial Plantar Nerve?
- Abductor hallucis
- Flexor digitorum brevis
- Flexor hallucis brevis
- First Lumbricalis
These muscles are important for foot movement and stability.
What do the articular branches of the Medial Plantar Nerve supply?
The tarsal and tarsometatarsal joints
These joints are crucial for foot mobility.
What is the Lateral Plantar Nerve also known as?
External Plantar Nerve
What is the origin of the Lateral Plantar Nerve?
It is a branch of the tibial nerve
Which areas of the foot does the Lateral Plantar Nerve supply?
Skin of the fifth digit and lateral half of the fourth digit
What muscles are primarily supplied by the Lateral Plantar Nerve?
Most of the deep muscles
Describe the pathway of the Lateral Plantar Nerve.
Runs obliquely forward with the lateral plantar artery to the lateral side of the foot
Where does the Lateral Plantar Nerve lie before dividing?
Between Flexor digitorum brevis and Quadratus plant
What happens to the Lateral Plantar Nerve after it divides?
It divides into a superficial and a deep branch
Which muscles does the Lateral Plantar Nerve supply before its division?
Quadratus plant and abductor digiti minimi
What are the common digital nerves supplied by the Lateral Plantar Nerve?
Fourth and fifth common digital nerves
What additional branches do the fourth and fifth common digital nerves give off?
Cutaneous and articular branches
