Lower Extremity Flashcards
Psoas major m.
- Origin: TP L1-L5, VB T12-L5
- Insertion: lesser trochanter of the femur
- Action: laterally flex the VC, balances and flex the trunk and flex the thigh when acting with iliacus
- Innervation: lumbar plexus L1-L3
Iliacus m.
- Origin: superior iliac fossa, ala of sacrum and anterior sacroiliac l.
- Insertion: lesser trochanter of femur, femoral shaft, and psoas major t.
- Action: Flex the thigh and stabilize hip joint
- Innervation: femoral n.
Sartorius m.
- Origin: ASIS
- Insertion: medial aspect proximal end of tibia (part of pes anserine)
- Action: flex, abduct, and laterally rotate thigh; flex leg at knee
- Innervation: femoral n.
Quadriceps femoris m.
- Rectus femoris m.
- Vastus lateralis m.
- Vastus intermedius m.
- Vastus medialis m.
REctus femoris m.
- Origin: straight head AIIS, reflected head ilium above acetabulum
- Insertion: base of patella; tibial tuberosity via patellar L.
- Action: extend leg at knee; assist iliopsoas m. In thigh flexion
- Innervation: femoral n.
Vastus lateralis m.
- Origin: greater trochanter lateral lip of linea aspera
- Insertion: lateral aspect of base of patella, tibial tuberosity via the patellar L.
- Action: extend leg at knee
- Innervation: femoral n.
Vastus intermedius m.
- Origin: anterior and lateral surface of femoral body
- Insertion: base of patella tibial tuberosity via patellar L.
- Action: extend leg at knee
- Innervation: femoral n.
Vastus medialis m.
- Origin: intertrochanteric line, medial lip of linea aspera
- Insert: medial aspect of base of patella, tibial tuberosity via patellar L.
- Action
- Innervation: femoral n.
Articulates genu m.
- Origin: anterior surface of distal femur
- Insertion: articulation capsule of knee
- Action: tightens capsule of knee during leg extension
- Innervation: femoral n.
Muscles of the anterior compartment of the thigh
- psoas major m.
- iliacus m.
- sartorius m.
- rectus femoris m.
- vastus lateralis m.
- vastus intermedius m.
- vastus medialis m.
- articulates genu m.
All 4 aponeuroses of the quadriceps femoris m. Insert into ______.
Patellar tendon
What does the femoral nerve (cutaneous) supply?
Anterior thigh and part of medial thigh
What does the saphenous nerve (cutaneous) supply?
Medial aspect of leg and ankle
Patellar reflex
L2-L4
Name the main branches of the femoral artery.
- external pudendal a.
- superficial epigastric a.
- superficial circumflex iliac a.
- medial femoral circumflex a.
- lateral femoral circumflex a.
- profunda femoris
What supplies the head and neck of femur?
Posterior retinacular a.
What provides blood supply to ligament of head of the femur?
Acetabular branch of the obturator artery
What can lead to avascular necrosis of the “femur”?
Posterior retinacular a.
What are the muscles of the medial compartment of the thigh?
- pectineus m.
- adductor longus m.
- adductor brevis m.
- adductor magnus m.
- gracilis m.
Gracilis m.
- Origin: body and inferior ramus of pubis
- Insertion: medial surface of tibia inferior to tibial tuberosity between the insertion of the sartorius and semitendinosus
- Action: adduct thigh, assist in medial thigh rotation, flex the leg
- Innervation: anterior division of obturator n.
Pectineus m.
- Origin: superior pubic ramus
- Insertion: pectineus line of femur
- Action: adduct and flex thigh
- Innervation: femoral n.
Adductor longus m.
- Origin: body and inferior to pubic crest
- Insertion: middle 1/3 of linea aspera
- Action: adduct thigh
- Innervation: anterior division of obturator n.
Adductor brevis m.
- Origin: body and inferior pubic ramus
- Insertion: pectineus line and proximal linea aspera
- Action: adduct thigh and assist in flexion
- Innervation: anterior division of obturator n.
Adductor magnus m.
- Origin: ischiopubic ramus & ischial tuberosity
- Insertion: pectineal line of femur
- Action: whole muscle - adduct thigh; hamstring - extend leg
- Innervation: (upper fibers) posterior division of obturator n. (lower fibers) tibial division of sciatic n.
Obturator External m.
- Origin: external surface of obturator membrane and surrounding margins of the obturator foramen
- Insertion: passes posterior to the neck of the femur to attach to the trochanteric fossa
- Action: lateral rotator of thigh; holds head of femur in acetabulum
- Innervation: anterior division of obturator nerve
Boundaries of the adductor canal
- anteromedial: sartorius m.
- lateral: vastus medialis m.
- posterior: adductor longus m. & adductor magnus m.
Adductor canal region
Runs from apex of femoral triangle to adductor hiatus
Contents of the adductor canal
- femoral artery
- femoral vein
- saphenous artery
- saphenous nerve
- nerve to vastus medialis m.
What exits the canal?
Popliteal artery and vein
What are the tributaries of the great saphenous vein?
- external pudendal vein
- superficial circumflex iliac vein
- superficial epigastric vein
Trace the route of the great saphenous vein.
Medial side of dorsal venous arch of foot —> medial side of leg and thigh —> terminates in femoral vein on anterior thigh (saphenous opening)
What does the inferior vertical group of superficial inguinal nodes drain?
Superficial tissue of lower extremity
What does the superior horizontal group of the superficial inguinal node drain into?
Anterior abdominal wall inferior to umbilicus, penis, scrotum, vulva, lower vagina, lower anal canal, lateral thigh
What structures do the superficial inguinal nodes NOT drain into?
Dorsolateral foot and posterior calf (popliteal lymph nodes)
Iliotibial tract (IT Band)
- fibers of the fascia lata of vertical orientation
- aponeuroses of gluteus maximus and tensor fascia lata
- inserts into Gerry’s tubercle (anterolateral tubercle of the tibia)
Boundaries of the femoral triangle
- superior boundary: inguinal ligament forms base of triangle
- medial boundary: lateral border of adductor longus muscle
- lateral boundary: medial border of sartorius m.
- apex of triangle: medial border of sartorius crosses lateral border of adductor longus
Floor of the femoral triangle
- iliacus m.
- psoas major m.
- pectineus m.
What muscles pass deep to the inguinal ligament?
- iliacus m.
- psoas major m.
What is the action of the iliacus and psoas major m.?
Flex at the hip
Roof of the femoral triangle
- fascia lata
- cribiform fascia
- subcutaneous tissue
- skin
Fascia lata
- surrounds entire thigh
- lies deep to subcutaneous fascia
- produces intermuscular septa which divides the thigh into 3 muscular compartments
Where is the retroinguinal space?
Deep to the inguinal ligament
Divisions of the retroinguinal space
- muscular compartment: iliopsoas and femoral n.
- vascular compartment: femoral artery, femoral vein, deep inguinal lymph node
Muscular branches of the femoral nerve
- iliacus m.
- quadriceps femoris m.
- sartorius m.
- pectineus m.
Muscular branches of the femoral nerve (cutaneous)
Femoral nerve:
- lateral femoral cutaneous n.
- anterior cutaneous branches of femoral n.
Saphenous nerve:
- infrapatellar branch of saphenous n.
- medial crural cutaneous branches of the saphenous n.
What are femoral vessels enclosed by?
Femoral sheath (fascia sleeve) which is deep to deep fascia (fascia lata).
Name the compartments of the femoral sheath
- lateral compartment (femoral artery)
- middle compartment (femoral vein)
- medial compartment (lymphatic structures)
Where is the femoral artery located?
femoral artery passes deep to inguinal ligament approximately half way between the ASIS and pubic tubercle
What is the superior opening of the femoral canal?
Femoral ring
Femoral hernia vs. inguinal hernia
Femoral hernia
- common in women > men
- loop of intestine forced into the femoral ring then expands to form a swelling in the upper part of the thigh
- below and lateral to pubic tubercle
Inguinal hernia
- above and medial to pubic tubercle
What do the deep inguinal lymph nodes receive?
- Deep lymph vessels of lower limb, perineal region, efferent vessels from the superficial inguinal ligament
- Drains into external iliac ligament
Trace the course of the great saphenous vein.
Medial side of dorsal venous arch of the foot to the medial side of leg and thigh then terminates in femoral vein on anterior thigh in saphenous opening (saphenous hiatus)
3 tributaries of great saphenous vein
- external pudendal v.
- superficial circumflex iliac v.
- superficial epigastric v.
Two groups of the superficial inguinal lymph nodes
- horizontal group: superior
- vertical group: inferior
Drains anterior abdominal wall inferior to umbilicus, penis, scrotum, vulva, lower vagina, lower anal canal, lateral thigh
Superior horizontal group of SIN
Drains superficial tissue of lower extremity
Inferior vertical group
- Drains anal canal below pectinate line, skin below umbilicus (except popliteal area) scrotum, vulva
- Pathology: STDs, medial foot/leg cellulitis, skin CA
Superficial inguinal nodes
Lateral femoral cutaneous n.
- L2-L3
- sensory anterior and lateral thigh
Femoral branch of genitofemoral nerve
- L1-L2
- sensory: scrotum, labia majora, medial thigh
- motor: cremaster m.
Obturator nerve
- L2-L4
- sensory: medial thigh
- motor: obturator externus, adductor longus, adductor brevis, gracilis, pectineus, adductor magnus muscles
Other cutaneous innervations
- intermediate femoral cutaneous n.
- medial femoral cutaneous n.
- ilioinguinal n.
- “gun belt palsy”
- impingement of lateral femoral cutaneous n.
- tingling numbness lateral thigh
Meralgia paresthetica
dense connective tissue that surrounds the entire thigh and lies deep to subcutaneous fascia
Fascia lata
Fascia lata is mostly (1) _____ fibers, except (2) ______, which is (3) _______.
- Horizontal fibers
- Iliotibial tract
- Vertical
Aponeuroses of gluteus Maximus and tensor fascia lata muscle which attaches to Gerdy’s tubercle (anterolateral tubercle of the tibia)
Iliotibial tract
Boundaries of the gluteal region
- superior: iliac crests
- inferior: gluteal sulcus (groove beneath gluteal fold)
Cutaneous nerves of the gluteal region
- superior cluneal nerves
- middle (medial) cluneal nerves
- inferior cluneal nerves
Superior cluneal nerves
Dorsal rami of L1-L3
Middle (medial) cluneal nerves
Dorsal rami of S1-S3
Inferior cluneal nerves
Ventral rami of S1-S3
Posterior femoral cutaneous nerve
Results in pain over the distribution of the superior and medial cluneal nerves
Nerve impingement in the lumbar spine
Trace lymphatic drainage of the gluteal region
- superficial tissues of gluteal region —> superficial inguinal nodes —> external iliac nodes*
- superior and inferior gluteal nodes —> internal and external iliac nodes
- *common iliac nodes —> lumbar (canal) lymph nodes —> cisterna chyli —> thoracic duct
Gateway to the pelvis
Greater sciatic foramina
Gateway to the perineum
Lesser sciatic foramina
Important ligament of the greater sciatic foramina
Sacrotuberous ligament (posterior sacrum to ischial tuberosity)
Important ligament for the lesser sciatic foramina
Sacrospinous ligament (posterior sacrum to spine of the ischium)
Things that run in the greater sciatic foramen
7 nerves:
- sciatic n.
- superior gluteal n.
- inferior gluteal n.
- pudendal n.
- posterior femoral cutaneous n.
- nerve to quadratics femoris
- nerve to obturator internus
3 vessel sets:
- superior gluteal a and v
- inferior gluteal a and v
- internal pudendal a and v
1 muscle: piriformis
Things that run in the lesser sciatic foramen
- tendon of obturator internus
- internal pudendal a and v
- pudendal n.
- nerve to obturator internus
Things that run in the greater and lesser sciatic foramen
- pudendal n.
- internal pudendal a and v
- nerve to obturator internus
Gluteus Maximus m.
- Origin: ilium posterior to posterior gluteal line, dorsal surface of sacrum, sacrotuberous ligament
- Insertion: IT band and gluteal tuberosity
- Action: extension, lateral rotation, rising from seated position
- Supplied by: superior and inferior gluteal arteries
- Innervation: inferior gluteal n. (L5-S2)
Gluteus medius m.
- Origin: external ilium between anterior and posterior gluteal lines
- Insertion: lateral surface of greater trochanter of the femur
- Action: abduct and medially rotate thigh
- Supplied by: superior gluteal a.
- Innervation: superior gluteal n. (L5-S1)
Gluteus minimums m.
- Origin: external ilium between anterior and inferior gluteal lines
- Insertion: anterior surface of greater trochanter
- Action: abduct and medially rotate thigh
- Supplied by: superior gluteal artery
- Innervation: superior gluteal n. (L5-S1)
Tensor fascia latae m.
- Origin: ASIS, anterior iliac crest
- Insertion: IT tract, lateral condole of tibia
- Action: abduct and medially rotate thigh
- Supplied by: lateral circumflex a.
- Innervation: superior gluteal n. (L5-S1)
Abduct and medially rotate thigh
- gluteus medius m.
- gluteus minimums m.
- tensor fascia latae m.
Lateral rotators and thigh extension/abduction
- piriformis m.
- obturator internus m.
- superior gemelli m.
- inferior gemelli m.
- quadratics femoris m.
Piriformis m.
- Origin: anterior surface of sacrum, sacrotuberous ligament
- Insertion: superior border of greater trochanter of femur
- Action: laterally rotate extended thigh and abduct flexed thigh
- Supplied by: inferior gluteal artery
- Innervation: nerve to piriformis m.
What is the only muscle in the greater sciatic foramen?
Piriformis m.
Obturator internus m.
- Origin: pelvic surface of obturator membrane
- Insertion: medial surface of greater trochanter of femur
- Action: laterally rotate extended thigh and abduct flexed thigh
- Supplied by: inferior gluteal artery
- Innervation: nerve to obturator internus (L5, S1)
What structure only passes through the lesser sciatic foramen?
Tendon of obturator internus
Superior gemelli m.
- Origin: ischial spine
- Insertion: medial surface of greater trochanter of femur
- Action: laterally rotate extended thigh and abduct flexed thigh
- Supplied by: inferior gluteal artery
- Innervation: nerve to obturator internus
Inferior gemelli m.
- Origin: ischial tuberosity
- Insertion: medial surface of greater trochanter of femur
- Action: laterally rotate extended thigh and abduct flexed thigh
- Supplied by: inferior gluteal artery
- Innervation: nerve to the quadratics femoris (L5-S1)
Quadratics femoris m.
- Origin: lateral border of ischial tuberosity
- Insertion: quadratics tubercle on the femur
- Action: laterally rotates thigh
- Supplied by: medial circumflex femoral A.
- Innervation: nerve to quadratics femoris (L5/S1)
Piriformis syndrome
Piriformis spasm and tightness can irritate nearby sciatic nerve
What structures exit the pelvic space through the greater sciatic foramen and pass through the lesser sciatic foramen to enter the perineum?
- pudendal nerve
- internal pudendal artery
- nerve to the obturator internus
Name the branches of the cruciate anastamosis
- inferior gluteal artery
- medial circumflex femoral artery
- lateral circumflex femoral artery
- first perforating branch of profunda femoris artery
Important nerves of the lumbosacral plexus
- cluneal nerves
- superior and inferior gluteal nerves
- sciatic nerve
- nerve to the quadratics femoris
- posterior cutaneous nerve of the thigh
- pudendal nerve
- nerve to the obturator internus
Caused by a lesion of the superior gluteal nerve
Trendelenburg sign (Duchenne’s Limp”
Trendelenburg sign
Caused by lesion of superior gluteal nerve —> denervation or weakness of gluteus medius and minimums mm. —> gluteal gait & pelvis drops on the side opposite the injury
How/where would you perform an IM intragluteal injection?
- place 2nd digit on the ASIS
- place 3rd digit on the tubercle of the iliac crest
- site of safe area for injection: superolateral area
What is the injection site for anesthetic block of the sciatic nerve?
A few centimeters inferior to the midpoint of the junction of the PSIS and superior part of the greater trochanter
When are anesthetic blocks of the sciatic nerve used?
- distal LE fractures or trauma
- distal LE pain due to sciatic nerve pathology
What causes injury to the sciatic nerve in the gluteal region?
- compression by piriformis
- spasm of piriformis
- complete and incomplete sections of sciatic nerve
