Muscle - Lower Limb Flashcards
iliopsoas - psoas major
with iliacus, two closely related muscles; fibers pass under inguinal ligament to insert into femur via a common tendor
origin: transverse processes, bodies, and discs of T12 and lumbar vertebrae
insertion: on and just below lesser trochanter of femur
action: flex trunk on thigh; flex thigh; lateral flexion of vertebral column (psoas specifically)
iliopsoas - iliacus
one of two closely related muscles; fibers pass under inguinal ligament to insert into femur via a common tendon. Iliacus more lateral than psoas major.
origin: iliac fossa and crest, lateral sacrum
insertion: on and just below lesser trochanter of femur
action: flex trunk on thigh; flex thigh
Sartorius
straplike superficial muscle running obliquely across anterior surface of thigh to knee
origin: anterior superior iliac spine
insertion: by an aponeurosis into medial aspect of proximal tibia
action: flexes, abducts, laterally rotates thigh; flexes knee; (“tailor’s muscle”)
adductors - magnus
part of large muscle mass forming medial aspect of thigh; arise from front of pelvis and insert at various levels on femur
origin - ischial and pubic rami and ischial tuberosity
insertion - linea aspera and adductor tubercle of femur
action - adduct and medially rotate and flex thigh; (posterior part of magnus also synergist in thigh extension
adductor longus **
part of large muscle mass forming medial aspect of thigh; arise from front of pelvis and insert at various levels on femur
origin - pubis near pubic symphysis
insertion - linea aspera
action: adduct and medially rotate and flex thigh
adductor brevis
part of large muscle mass forming medial aspect of thigh; arise from front of pelvis and insert at various levels on femur
origin - body and inferior pubic ramus
insertion - linea aspera
action - adduct and medially rotate and flex thigh
pectineus
overlies adductor brevis on proximal thigh
origin - pectineal line of pubis (and superior pubic ramus)
insertion - inferior from lesser trochanter to linea aspera of femur
action - adducts, flexes, and medially rotates thigh
gracilis **
straplike superficial muscle of medial thigh
origin - inferior ramus and body of pubis
insertion - medial surface of tibia just inferior to medial condyle
action - adducts thigh; flexes and medially rotates leg (esp during walking)
rectus femoris **
superficial muscle of thigh; runs straight down thigh; only muscle of group to cross hip joint
origin - anterior inferior iliac spine and superior margin of acetabulum
insertion - tibial tuberosity and patella
action - extends knee and flexes thigh at hip
vastus lateralis
forms lateral aspect of thigh; intramuscular injection site
origin - greater trochanter, intertrochanteric line, and linea aspera
insertion - tibial tuberosity and patella
action - extends and stabilizes knee
vastus medialis
forms inferomedial aspect of thigh
origin - linea aspera and intertrochanteric line
insertion - tibial tuberosity and patella
action - extends knee; stabilizes patella
vastus intermedius
obscured by rectus femoris; lies between vastus lateralis and vastus medialis on anterior thigh
origin - anterior and lateral surface of femur
insertion - tibial tuberosity and patella
action - extends knee
tensor fasciae latae
enclosed between fascia layers of thigh
origin - anterior aspect of iliac crest and anterior superior iliac spine
insertion - iliotibial tract (lateral portion of fascia lata)
action - steadies trunk (flexes, abducts, and medially rotates thigh)
gluteus maximus
largest and most superficial of gluteal muscles; intramuscular injection site
origin - dorsal ilium, sacrum, coccyx
insertion - gluteal tuberosity of femur and iliotibial tract
action - complex, powerful thigh extensor; (antagonist of iliopsoas; laterally rotates and abducts thigh)
gluteus medius **
partially covered by gluteus maximus; intramuscular injection site.
origin - upper lateral surface of ilium
insertion - greater trochanter of femur
action - abducts and medially rotates thigh (steadies pelvis while walking)
gluteus minimus
smallest and deepest gluteal muscle
origin - external inferior surface of ilium
insertion - greater trochanter of femur
action - abducts and medially rotates thigh (steadies pelvis)
hamstrings - biceps femoris
most lateral muscle of group; arises from two heads
origin - ischial tuberosity (long head); linea aspera and distal femur (short head)
insertion - tendon passes laterally to insert into head of fibula and lateral condyle of tibia
action - extends thigh; flexes knee; (laterally rotates leg)
fibularis (peroneus) longus **
superficial lateral muscle; overlies fibula
origin - head and upper portion of fibula
insertion - by long tendon under foot to metatarsal I and medial cuneiform
action - plantar flexes and everts foot (keeps foot flat on ground)
fibularis (peroneus) brevis
smaller muscle; deep to fibularis longus
origin - distal portion of fibular shaft
insertion - by tendon running behind lateral malleolus to insert on proximal end of metatarsal V
action - plantar flexes and everts food (part of fibularis group)
tibialis anterior
superficial muscle of anterior leg; parallels sharp anterior margin of tibia
origin - lateral condyle and upper 2/3 of tibia; interosseous memb
insertion - by tendon into inferior surface of first cuneiform and metatarsal I
action - prime mover of dorsiflexion; (inverts foot, supports longitudinal arch of foot
extensor digitorum longus
anterolateral surface of leg; lateral to tibialis anterior
origin - lateral condyle of tibia; proximal 3/4 of fibula; interosseous memb
insertion - tendon divides into four parts; inserts into middle and distal phalanges of toes 2-5
action -prime mover of toe extension (dorsiflexes foot)
fibularis (peroneus) tertius
small muscle; often fused to distal part of extensor digitorum longus
origin - distal anterior surface of fibula and interosseous memb
insertion - tendon inserts on dorsum of metatarsal V
action - dorsiflexes and everts foot
Extensor hallucis longus
deep to extensor digitorum longus and tibialis anterior
origin - anteromedial shaft of fibula and interosseous memb
insertion - tendon inserts on distal phalanx of great toe
action - extends great toe (dorsiflexes foot)
triceps surae
refers to muscle pair below that shapes posterior calf
origin -
insertion - via common tendon (calcaneal) into calcaneus of heel
action - plantar flex foot
