Nerves And Vessels Flashcards
Describe the Femoral Nerve under — origin, course, branches.
Nerve to Vastus medialis is very thick. It carries proprioceptive fibres from knee and also supplies the Articularis genu muscle.
ORIGIN: It is the largest branch of the Lumbar plexus. Formed by dorsal branches of ventral rami of L2,L3, L4 spinal nerves.
COURSE:
- Appears in the iliac Fossa under cover of fascia iliaca.
- Enters the femoral triangle deep to the Inguinal ligament, on the lateral side of femoral artery.
- After a short course of 2-3cm below the Inguinal ligament, it divides into Ant. and Post. divisions in the femoral triangle, which are separated by the lateral circumflex femoral artery.
BRANCHES
1) Trunk- Muscular branch to Pectineus and iliacus
2) Ant Division- 1 muscular (Sartorius) 2 cutaneous (Medial and Intermediate cutaneous nerves of the thigh)
3) Post Division- 4 muscular ( to Rectus Femoris, and the three vasti) 1 cutaneous (Saphenous nerve). The nerve to Rectus femoris also gives an articular br to hip joint. And the nerves to the vasti supply the knee joint.
Profunda Femoris— Origin, Course, Branches.
ORIGIN: Lateral side of the femoral artery in the femoral triangle, 4cm below the Inguinal ligament.
COURSE:
1) As it descends, it passes medially behind the femoral vessel.
2) Leaves the femoral triangle by passing deep to Adductor longus.
3) First passes b/w Add.longus and Add.brevis
4) Then passes b/w Add.longus and Add.Magnus
5) Pierces the Add.Magnus and ends by anastomosing with the Superior muscular branch of Popliteal artery.
BRANCHES:
1) Medial circumflex femoral - gives acetabular, ascending and transverse branches
2) Lateral Circumflex femoral - has ascending, transverse & descending branches
3) Perforating arteries - 3 perforating arteries are branches, 4th one is the continuation of the Profunda femoris itself.
Describe the branches of the Profunda femoris.
1) Medial circumflex femoral- leaves the femoral triangle by passing posteriorly b/w the psoas major and Pectineus. It gives off an acetabular branch which supplies the fovea capitis of head of femur. It ends by dividing into — Ascending branch (part of Trochanteric anastomosis)and transverse branch ( part of cruciate anastomosis)
2) Lateral circumflex femoral- passes laterally b/w the anterior and posterior divisions of femoral nerve. It leaves the triangle by going deep to Sartorius and Rectus femoris. Divides into — Ascending, Transverse and Descending branches.
- Ascending br- passes upward, deep to Iliotibial tract, supplies hip joint and anastomoses with Sup Gluteal art.
- Transverse br- pierced Vastus lateralis, supplies cruciate anastomosis
- Descending br- runs downward along anterior border of Vastus lateralis. Ends in the anastomosis around the knee.
3) Perforating arteries- they pierce the Adductor Magnus and Lateral inter-muscular septum, supply the Adductor muscles and the Hamstrings. End in the Vastus lateralis where they form anastomosis at the back of the thigh.
—1st perf artery arises at upper border of Adductor brevis, 2nd one in front of it and the 3rd one just below it.
Femoral Artery — origin and course.
Origin: cont of Ext iliac artery. Enters the femoral triangle deep to the Inguinal ligament at the mid-Inguinal point.
Course:
- Enters the femoral triangle
- Passes downwards and medially and leaves the triangle at the apex, deep to Sartorius
- Traverses Adductor canal
- At the lower end of adductor canal it passes through the 5th Osseo-aponeurotic opening, at the juncn of Middle 1/3rd and lower 1/3rd of thigh.
- Appears in the popliteal fossa as popliteal artery.
Branches— 7 branches
Obturator Nerve— Origin, Course, Branches.
It is branch of Lumbar plexus.
Root value: Ventral branches of ventral rami of L2,L3 and L4 spinal nerves.
ORIGIN: - Emerges at the medial border of psoas major muscle in the abdomen.
-Crosses the pelvic brim and runs downwards and forwards in the lateral pelvic wall.
-Enters the thigh by passing through the Obturator canal.
-Ends by dividing into ant and post divisions in the Obturator canal.
Ant division: Passes in front of the Obturator externus. Then it lies between pectineus and Adductor longus Anteriorly and the adductor previs posteriorly.
Posterior division: Pierces the Obturator externus, passes behind adductor brevis and in front of adductor magnus. Ends by giving muscular, articular and vascular branches.
BRANCHES
Ant div: Muscular to Pectineus, Adductor longus, brevis and gracilis. Articular to hip joint. Vascular to femoral artery.
Post div: muscular to Obturator externus and Adductor Magnus (adductor part). Articular to knee. Vascular to popliteal artery.
Popliteal artery— origin and course with branches.
- Begins at the 5th osseo-aponeurotic opening as a continuation of Femoral artery.
- Runs downwards and laterally to the lower border of popliteus.
- Terminates here by dividing into Ant Tibial and Post Tibial arteries.
Branches:
1) Upper Muscular branches to Hamstrings and Adductor Magnus, anastomoses with 4th perforating branch of Profunda femoris art.
2) Lower muscular branch supplies Soleus, Gastrocnemius and Plantaris.
3) Cutaneous branches - Sural branch accompanied Small saphenous vein.
4) 5 genicular branches.
Common Peroneal Nerve course.
- Smaller terminal branch of Sciatic nerve.
- Begins at the superior angle of Popliteal fossa.
- Passes downwards and laterally to the lateral angle.
- Passes forwards and downwards by winding around neck of fibula and pierced the peroneus longus.
- Divides into Superficial and Deep peroneal nerves.
What is foot drop? Cause?
It is a condition where the floor hands down, remains fully plantarflexed and cannot be dorsiflexed.
This is due to paralysis of dorsiflexors (ant compartment of leg).
Person has high-stepping gait.
Cause:
Injury to common peroneal nerve
Injury to sciatic nerve
(not deep peroneal)
Deep peroneal nerve injury causes— ?
Talipes equinovalgus.
Foot is plantar flexed and everted.
Paralysis of dorsiflexors (4 muscles of ant compartment)
Paralysis of invertors (Tibialis anterior)
