L15: Musculo-neuro-vascular systems of the anterior and posterior compartments of the thigh Flashcards
surface anatomy of the Anterior Thigh
ASIS: Anterior superior iliac spine
Tensor Fasciae Latae
Sartorius
Vastus Lateralis
Rectus Femoris
Vastus Medialis
Iliotibial Tract
Patella
surface anatomy of Lateral thigh
Gluteus maximus and tensor fasciae latae insert into iliotibial tract
At the knee, the iliotibial tract narrows as it approaches its insertion (lateral tibial condyle(Gerdy ’s tubercle) and is quite superficial (9)
Tendon of biceps fermoris is just posterior to this
surface anatomy of Posterior Thigh
Gluteal Fold
Iliotibial Tract
Tendons at the Knee:
*Semitendinosus (medially)
*Biceps Femoris Long Head (laterally)
Popliteal Fossa, you can take your pulse from here!
fascia of the thigh
*Fascia (connective tissue) divides the lower limb into compartments, just like it did with the upper limb.
*Superficial thigh is covered by fascia lata
*Fascia lata is thickened on the lateral thigh and is called the iliotibial tract or band. Tensor fascia latae is a muscle that tightens this band
Thigh compartments
Fascia lata and its septae divide the thigh into three compartments:
*Anterior compartment
*Posterior compartment
*Medial compartment
Each compartment has its own main innervation which supplies most of the muscles of that compartment
Muscles of thigh; Anterior Compartment (8)
- pectineus
- Iliopsoas
- psoas major
- iliacus
- sartorius
- quadriceps femoris
- rectus femoris
- vastus lateralis
- vastus medialis
- vastus intermedius
muscles of the thigh; Posterior compartment (3)
- semitendinosus
- semimembranosus
- biceps femoris
pectineus, origin + insertion
origin: superior pubis ramus (pectineal line)
insertion: pectineal line of femur, inferior to lesser trochanter
Pectineus, Innervation + action
innervation: femoral nerve (L2,L3), sometimes branch from obturator nerve contributes too
actions: adducts hip, flexes hip, externally rotates hip
Iliopsoas, origin + insertion:
iliopsoas: Psoas major and iliacus
Origin:
- Psoas major: lateral part of T12-L5 vertebral bodies
- Iliacus: iliac fossa and crest, ala of sacrum, and sacro-iliac ligaments
insertion: Both muscles merge to insert into lesser trochanter of femur
Iliopsoas, innervation + actions
innervation:
- psoas major: direct branches from L1-3 anterior rami
- iliacus: femoral nerve (L2,L3)
Actions: flexes thigh at hip. most powerful hip flexor, lateral rotation at hip, stabilisation of leg when standing, maintenance of posture
Sartorius, origin + insertion
longest muscle in the body, crosses hip and knee joints
origin: ASIS- Anterior Superior Iliac Spine
Insertion: medial to tibial tuberosity
Sartorius, innervation + actions
innervation: femoral nerve
actions: flexes, abducts, externally rotates thigh at hip joint, flexes leg at knee joint
Rectus Femoris, origin + insertion
This muscle has 2 heads and sits superficial to vastus intermedius
origin:
- straight head: AIIS
- Reflected head: Ilium, superior to acetabulum
insertion: quadriceps tendon, and hence into tibial tuberosity via patellar ligament
Vastus Lateralis; origin + insertion
origin: greater trochanter and lateral lip of linea aspera of femur
insertion: quadriceps tendon, and hence into tibial tuberosity via patellar ligament
Vastus Lateralis; innervation + action
innervation: femoral nerve
action: extends leg at knee joint
Vastus Medialis; origin + insertion
origin:
- intertrochanteric line of femur
- medial lip of linea aspera of femur
Insertion: quadriceps tendon, and hence into tibial tuberosity via patellar ligament
Vastus Medialis; innervation + Action
innervation: femoral nerve
action: extends leg at knee joint
Vastus Intermedius; origin + insertion
lies deep to rectus femoris. Only visible if rectus is resected.
origin: anterior and lateral shaft of femur
Insertion: quadriceps tendon, and hence into tibial tuberosity via patellar ligament
Vastus Intermedius; innervation + action
innervation: femoral nerve
action: extends leg at knee joint
Patellar Disclocation
caused by a direct blow to patella or sudden twist of leg
patella slips from its normal position in the patellofemoral groove
usually slips laterally
Patellar Fracture
- usually caused by trauma directly to anterior knee or sudden contraction of quadriceps
- if bony fragments become displaces, requires surgery to reapproximate the fragments
- if bony fragments are nondisplaced, knee immobilised in cast for 6 weeks
Semitendinosus; origin + insertion
in between semimembranosus and biceps femoris
origin: ischial tuberosity
insertion: medial to tibial tuberosity, part of pes anserinus
Semitendinosus; innervation + actions
innervation: tibial division of sciatic nerve
actions: extends hip joint, flexes knee joint, medial rotation of leg at knee when knee is flexed, can extend trunk when rising from seated position
Semimembranosus; origin + insertion
most medial of the three hamstrings
origin: ischial tuberosity
insertion:
-posterior part of medial tibial condyle
-oblique popliteal ligament
Semimembranosus; innervation + action
innervation: sciatic nerve (tibial division)
actions: extends thigh at hip joint, flexes leg at knee joint, internal rotation of leg at knee when knee is flexed
Biceps femoris; origin + insertion
most lateral of the 3. this muscle has 2 heads: long and short head
origin:
- long head: ischial tuberosity
- short head: lateral part of linea aspera in middle third of femur, lateral supracondylar line
insertion: lateral part of fibular head
Biceps Femoris; innervation + actions
innervation:
-long head: sciatic nerve (tibial division)
-short head: sciatic nerve (fibular division)
actions: extends thigh at hip joint, flexes leg at knee joint, external rotation of leg at knee joint when knee is flexed
Hamstring in situ
‘‘MTLS’’
Medial to lateral
- Membranosus
- Tendinosus
- Long head
- Short head
Muscle injury grades: 1-3
- minor tear or overstretch of muscle fibres. Pain but function intact
- Partial tear across muscle. Pain and weakened function
- Complete tear across muscle. Pain and complete loss of function
Thigh: cutaneous innervation
Cutaneous (sensory) innervation of the thigh is provided mostly by cutaneous branches of the femoral nerve
*Anterior and medial surface: anterior and medial cutaneous branches of the femoral nerve
*Posterior surface: posterior femoral cutaneous nerve
*Lateral surface: lateral femoral cutaneous nerve
Other contributions include:
*Genitofemoral nerve
*Cutaneous branch of obturator nerve
arterial supply to lower limb
heart
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Descending Aorta
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Common iliac artery
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internal iliac artery external iliac artery
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supplies gluteal region goes on to become
& pelvic region femoral artery
femoral artery
where does it come from?
*Inguinal Ligament is a complex ligament strung between ASIS and the pubic tubercle.
*As external iliac artery passes under the midpoint of inguinal ligament it changes name to femoral artery
*Femoral Artery supplies very little of thigh directly.
*It gives off a deep branch, profunda femoris, which supplies the thigh
Profunda Femoris
*Arises from postero-lateral part of femoral artery in the femoral triangle (next lecture)
*Medial and lateral circumflex femoral branches supply proximal femur (neck + head)
*It runs deep in the thigh, alongside the femur supplying it and the deep muscles of the thigh
*Perforating branches: These wrap around the femur and supply all 3 thigh compartments. Usually there are 3-4 in total.
*Descending genicular branch: These supply the proximal knee
Femoral Artery
where does it go ?
*Distally, it passes posterior to femur through a gap in the adductor magnus muscle called the adductor hiatus.
*It continues distally to enter the space at the back of the knee; the popliteal fossa.
*At this point the femoral artery becomes known as the popliteal artery.
venous drainage of the lower limb
right atrium of heart
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inferior vena cava
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common iliac vein
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internal iliac vein external iliac vein
^ ^
superior and inferior common femoral
gluteal vein vein (main vein of
thigh)
Venous drainage of thigh
superficial system
Superficial System
*The superficial regions of the thigh are drained by the Great Saphenous Vein
*Subsequently, the Great Saphenous Vein pierces through a gap in the fascia lata and drains directly into the Common Femoral Vei
Venous Drainage of Thigh
Deep system
Deep System
*The deep regions of the thigh are drained by 3-4 deep perforating veins which subsequently drain into the profunda femoris vein
*The profunda femoris vein subsequently joins with the femoral vein to form the common femoral vein
