Arteries + Veins + nerves of LL (pathways+imp. locations) Flashcards
Branches of the lumbosacral plexus
Lumbar plexus:
- formed by the anterior rami of L1-L3 and part of L4
- located within the psoas major musc.
Lumbosacral Trunk:
- Formed by the remainder of the anterior rami of the L4 + anterior rami of L5
Sacral Plexus:
- The lumbosacral trunk enters the pelvis to join the anterior rami of S1-3 and part of S4 to form the sacral pexus
- Located on the posterolateral aspect of the wall of the pelvis
Branches of the Lumbar plexus in the LL
–Femoral nerve
– Obturator nerve
– Illoinguinal nerve
– Genitofemoral nerve
– Lateral cutaneous nerve of thigh
– Motor branches (to illiopsoas)
Femoral nerve - pathway + branches + innervation
L2-L4
- Originates from L2-L4 of lumbar plexus
- Emerges from lateral part of psoas major
- Passes behind the inguinal ligament in the groove between psoas major and illiacus
- Enters the fem triangle
—-» Here it is split into its posterior and anterior divisions by the lateral circumflex femoral artery - give rise to sensory and motor branches of the fem n.
Motor branches supply:
- All anterior compartment muscles except for illiopsoas musc.
- Pectineus in the medial compartment
Sensory branches:
- Medial fem cutaneous n. (anteromedial aspect of thigh)
- Intermediate fem. cutaneous n. (anteromedial aspect of thigh)
- Saphenous nerve (anteromedial aspect of leg)
sensory innervation to:
- the knee and hip joints
- skin on the anteromedial aspect of the LL to the medial aspect of the foot
The SAPHENOUS N. :
- main sensory branch of the fem. n.
- Enters the add. canal but doesnt leave thru the add. hiatus in the posterior thigh instead travels MEDIALLY
- Instead emerges btwn SARTORIUS and GRACILIS
- To run SUPERFICIALLY down the medial aspect of the leg
- Here it accompanies the GREAT SAPH. V.
- Also gives off infrapatellar and medial crural cutaneous branches
INNERVATION: anterior and medial aspect of the leg and medial side of the foot
Saphenous nerve pathway + innervation + Damage to it?
PATHWAY:
- Largest sensory branch of Fem n.
- Fem. n. gives off this branch in the add. canal - runs with fem vessels (V. + A.)
- Doesnt leave thru add hiatus
- Instead pierces sartorius and gracilis to run superficially and down the medial side of the leg.
- Here it accompanies the GREAT SAPH. V.
- Gives off infrapatellar and medial crural branches in the medial leg
INNERVATION:
- Skin on anterior and medial leg
- Skin on medial side of foot
DAMAGE:
when varicose veins are stripped
What accompanies the Great saph Vein?
The saphenous nerve
Obturator Nerve - Pathway+innervation+associated injuries/diseases/pain
L2-L4
PATHWAY:
– Originates from L2-L4 of lumbar plexus
- Emerges from MEDIAL border of psoas major
- Travels thru obturator canal in upper part of the obturator foramen
- Pierces the obturator externus muscle
- After this it splits into its posterior and anterior branches
—> Anterior branch - anterior to ADDUCTOR BREVIS
—-> Posterior branch - post. to add. brevis
INNERVATION:
—-> Motor:
- All medial compartemnt musc. of thigh except pectineus (fem n.) and hamstring part of add. magnus (sciatic n.)
- Obturator externus (small musc. of hip but also included in medial compartment of thigh)
—–> Sensory:
- Hip and knee joints (*referred pain)
- Innervates the skin on upper part of the medial thigh (** referred pain)
REFERRED PAIN:
* Since obt. n. innervates hip and knee joints
– pain from hip disease can be felt as knee pain - patient presents with knee pain symptoms
** Obt. n. innervates medial part of upper thigh
– Pain from PELVIC INFLAMMATION felt here
Which muscle are the anterior and posterior branches of the obturator n. ant. and post. in relation to?
Adductor brevis muscle
Ilioinguinal nerve - L1
- Pierces the transverse abdominis
- SUPPLIES:
– penis + scrotum
– medial side of upper thigh
– strip of skin above inguinal ligament
Genitofemoral nerve - L1 + L2
- descends on anterior psoas major
SUPPLIES:
– Its femoral branch supplies skin on anterior central part of thigh
Lateral cutaneous nerve of thigh/Lateral fem. cutaneous nerve – Pathway+innervation+injuries
L2-L3
PATHWAY:
- originates from L2-L3
- Travels superior to and laterally on iliacus muscle
- Passes under lateral part of inguinal ligament
- Travels down lateral side of the thigh
SUPPLIES:
- Skin on lateral aspect of the thigh
INJURY:
Meralgia Paresthetica:
– Tingling, numbness and burning pain on outer thigh
– Due to compression of nerve
– tight clothing, pregnancy, obesity –> common causes
Motor branches of lumbar plexus
Supply iliacus and psoas major
Two main arteries supplying anterior and medial thigh?
Obturator Artery - branch of internal iliac A.
Femoral artery - Branch of external iliac A.
Largest branch of the femoral artery?
Profunda femoris (Deep branch of fem A.)
Branches of the profunda femoris? which ones and where they anastomose?
branches:
- Lateral circumflex femoral - supplies head and neck of femur, anterior part of gluteal region + femur +knee jt.
- Medial circumflex femoral - Head and neck of femur
- Perforating branches - Perforate add. magnus and supply posterior compartment of thigh
ANASTOMOSIS:
- medial and lateral circ. fem. A. anastomose encircle the uppermost part of the shaft of the femur and anastomose
Main blood supply to hip joint by?
Branches of profunda fem:
- Lateral circumflex femoral
- Medial circumflex femoral
Acetabular branch of obturator A.
Anastomosis arnd hip joint - which arteries are involved?
- Inferior gluteal artery
- Medial and lat circum. fem. arteries
- 1st perforating branch of profunda fem.
How is the Fem A. clinically important?
- Pressure over the Fem. A can be applied to control heammorhage from the LL
- Radiologists use catheterisation of Fem A to gain access to arterial circulation
- Cardiologists also use catheterisation of the Fem. A. to reach the coronary arteries to perform coronary angiography
- One of the most common site for peripheral arterial disease – artery narrowed resulting in decreased blood supply to the LL.
Obturator Artery - Pathway, branches, supply
- Branch of internal iliac A.
- Exits pelvis and enters medial compartment of the thigh through the obturator canal in the upper part of the obturator foramen
- Accompanies the obturator nerve
- As it passes thru obturator canal it gives off branches
BRANCHES:
- Posterior and anterior branches – encircle the obturator membrane margin
- Acetabular branch – enters hip joint by passing thru the acetabular notch and the ligament of the head of the femur to supply the head of the femur
Venous drainage of LL - write a note on it
Has superficial, deep and perforating veins similar to in the UL
Superficial veins:
- The lateral part of the dorsal venous arch in the foot drains into the small saphenous vein and the medial part of the arch drains into the great saphenous vein.
- Great Saph V. –>
> Medial part of dorsal venous arch drains into great saph.
> Travels anterior to medial malleolus and travels up the medial side of the LL
> Drains into the Fem. V. (deep vein) after passing thru the saphenous opening
» Saphenous opening lies inferior to the medial end of the inguinal ligament - Small Saph. V. –>
> Travels up the posterior side of the leg
> Drains into the popliteal Vein behind the knee
Deep veins:
- Accompany the arteries of the LL
Perforating Veins:
- Communicating veins between the deep and superficial veins
- Valves in these veins only allow flow from superficial to deep veins
Where does the saphenous opening lie?
Inferior to the medial end of the inguinal ligament
What issue/disease may be associated with the deep veins of the LL
Deep Vein thrombosis – blood clot formed in calf veins for example may travel up the Fem V. and eventually enter the Pulm. Artery and block circulation
** increased chance of occurring after surgery
Which vein in the LL is frequently used for venous access
Fem. Vein in the fem triangle - easy access
Used in shocked patients w/ v low pressures
What makes the Sacral plexus in the lower limb?
Lumbosacral trunk ( part of anterior rami of L4 and whole L5) joined with S1 - S3 and a little of S4 forms the sacral plexus
Branches of sacral plexus in LL?
- Sciatic nerve
- Gluteal nerves (inferior+superior)
- Motor branches
- Posterior cutaneous nerve of thigh
- Pudendal nerve
