Part 1: Anterior Compartment of Thigh Flashcards
Where does ilioinguinal nerve originate and what does it supply?
Collateral branch of iliohypogastric (L1). Runs in NV plane (between transverse abdominis and internal oblique) in abdominal wall. Emerges in front of cord in superficial ring and supplies root of penis, anterior 1/3 scrotum and small area of thigh. Cutaneous only.
Where does femoral branch of genitofemoral nerve arise and where does it innervate?
1st and 2nd lumbar nerves. Femoral branch arises as nerve lies on psoas. Runs down external iliac a. and supplies most of skin over femoral triangle. Cutaneous branch.
Where does medial femoral cutaneous nerve arise and what does it innervate?
Branch of anterior divisions of femoral nerve (L2,L3). Supplies medial side of thigh with terminal twigs to patella plexus
Where does intermediate femoral cutaneous nerve arise and what does it innervate?
Common origin with medial femoral cut n (anterior division of femoral nerve, L2,L3). Passes vertically down beneath fascia lata to supply anterior thigh to knee
Where does the lateral femoral cutaneous nerve arise and what does it innervate?
Branch of lumbar plexus (L2,L3). Passes beneath then within iliac fascia then beneath inguinal ligament just medial to ASIS. Divides into:
- anterior(L3) branch - supplies anterolateral surface of thigh
- posterior(L2) branch - supplies posterolateral aspect of thigh
What are the 4 cutaneous branches of the femoral artery?
Superficial circumflex artery
Superficial epigastric artery
Superficial external pudendal artery
Deep external pudendal artery
Describe the course of the great saphenous vein
Arises as continuation of medial marginal vein of foot. Spirals backwards where it lies a handsbreadth behind the medial border of patella. Spirals forward again and pierces cribriform fascia to to join the femoral vein
What are the 3 main groups of lymph nodes in anterior thigh and where do they drain from?
Large lymphatic vessel accompanies great saph v. and joins with other vessels to form “T” pattern.
Vertical group: drain from lower limb
Lateral group: Receive from buttock, flank and back
Medial group: receive from below umbilicus and perineum and external genitalia (excludes testes)
Describe what happens to Scarpa’s fascia in the lower limb?
Extends below IL and fixes to fascia lata at flexure skin crease of hip where attachment of skin to fascia lata prevents further descent. The saphenous opening is below this line - hence femoral hernia cannot fill space beneath Scarpa’s fascia.
Fascia lata encloses thigh like a stocking. Describe the IT tract
Iliotibial tract is thickening of fascia lata - passes vertically down to be inserted in anterior surface of lateral condyle of tibia. Helps stabiles hyperextended knee. Also attached to lateral IM septum.
Describe tensor fascia lata and the role it plays
Arises from external lip of iliac crest and ASIS. Passes down and inserts into IT tract. Innervated by superior gluteal nerve, pulls up on IT tract and aids in knee extension and stabilisation - especially hyperextended knee.
What are the boundaries of the femoral triangle?
Lat: Medial border sartorius
Med: Medial border adductor longus
Sup: Inguinal ligament
Floor: iliacus, psoas, pectineus, glimpse of adductor brevis
What is the contents of femoral triangle?
Femoral nerve, artery and vein
(Femoral sheath)
Deep inguinal nodes
What is the origin, attachment, innervation and action of sartorius?
O: Immediately below ASIS
I: Upper med surface of shaft of tibia
A: Flexes, abducts and laterally rotates the thigh at hip. Weak mover.
N: Anterior division of femoral nerve
What is the origin, attachment, innervation and action of Iliacus?
O: Iliac fossa (in pelvis)
I: Lowermost surface of LT
A: Flexes hip
N: Femoral nerve in abdomen
What is the origin, attachment, innervation and action of Psoas Major?
O: Transverse process of L1-5 and bodies of T12-L5 and intervertebral discs below body of T12-L4.
I: Middle surface of LT
A: Flexes hip
N: First 3 lumbar nerves (mainly L2)
What is the origin, attachment, innervation and action of Pectineus?
O: Pectineal line of pubis and narrow area of sup pubic ramus below it
I: Vertical line between spiral groove and gluteal crest below LT.
A: Flexes and adducts hip
N: Anterior division of femoral nerve (L2,3)
What is the femoral sheath?
Funnel shaped prolongation of the extra-peritoneal fascia derived from transversalis fascia in front and psoas fascia behind. This prolongation of fascia fuses with vessels adventita about 2.5cm below inguinal ligament. Contains artery and vein, femoral nerve is not part of sheath as it arises behind abdomen thus does not need to pierce fascia.
What is the purpose of the femoral sheath?
Gives freedom for femoral vessels to glide in and out beneath IL during movement of hip
What is the femoral space/canal?
Medial side of femoral vein within femoral sheath
- this space allows for dilation of vein
- holds lymph vessels
What are the boundaries of the femoral ring?
Anterior: medial part of IL
Medial: Crescentic edge of lacunar ligament
Posterior: Pectineal ligament
Lateral: Femoral vein
Where does the femoral artery enter the anterior thigh?
Midway between ASIS and pubic symphysis, just medial to deep inguinal ring
Describe the course of the femoral artery
Enters under IL. Emerges from femoral sheath, enters adductor canal. Has 4 small branches below IL and just after termination of sheath gives off profunda femoris.
What are the branches of profunda femoris?
Lateral circumflex femoral artery: different card
Medial circumflex artery: different card
Perforating arteries: pass backwards and upwards to supply adductors and hamstrings
