(Lesson 9) Lower Muscles Flashcards
External abdominal oblique
Paired muscle forming the outermost layer of the lateral abdominal wall;
compresses abdominal wall, rotates trunk
Internal abdominal oblique
Paired muscle forming the middle layer of the lateral abdomen;
Compresses abdomen similar to external oblique
Transversus abdominis
deepest muscle in abdominal area;
compresses abdominal wall
Rectus abdominus
runs vertically on the anterior medial portion of the abdominal wall;
compresses and allows lateral rotation of vertebral column
Linea Alba
vertical midline band of connective tissue within the abdominal wall
inguinal ligament
extends from crest of ilium to the pubic tubercle; derived from aponeurosispsoas major
psoas major
round muscle adjacent to iliacus;
flexes hip and rotates femur laterally, flexes vertebral column
Quadratus lumborum
originates on iliac crest, located deep next to the kidneys;
extends lumbar spine
Erector Spinae
Composed of three muscle groups: Spinalis, logissimus, ilicostalis
Spinalis
originates on spinous process of upper lumbar and lower thoracic,
inserts on spinous process of upper thoracic vertebrae;
extends vertebral column
Longissimus
Originates on transverse process of vertebrae, except upper cervical,
Inserts on spinous process of upper thoracic vertebrae;
Extends vertebral column
Iliocostals
Originates on ribs and crest of ilium,
inserts on posterior part of ribs and transverse process of cervical vertebrae;
Extends vertebral column
Serratus posterior, superior
located on the inferior and lateral portion of the back deep to the latissimus dorsi
serratus posterior inferior
located on the inferior and lateral portion of the back deep to the latissimus dorsi
Multifidius
very thin muscle that runs on either side of the spinous processes of the vertebrae from the sacrum to the axis;
originates on the sacrum, erector spinae aponeurosis, posterior superior iliac spine, and the iliac crest
inserts on the spinous processes;
Stabilizes the vertebrae
Medial Meniscus
C-shaped fibrocartilage located within the medial condyles providing cushion within the knee joint
lateral meniscus
C-shaped fibrocartilage located within the lateral condyles to provide cushion within the knee joint
anterior cruciate ligament
tendon connecting the posterior side of the femur to the anterior surface of the tibia preventing anterior sliding of the tibia
posterior cruciate ligament
tendon connecting the anterioinferior femur to the posterior tibia preventing posterior displacement of the tibia
lateral (fibular) collateral ligament
tendon located on the lateral surface of the knee joint providing stability and prevents hyperadduction of the leg at the knee
medial (tibular) collateral ligament
tendon located on the medial surface of the knee joint providing stability and prevents hyperabduction of the leg at the knee
iliopsoas
composed of two muscles as they join at the inguinal ligament: iliacus/psoas major
iliacus
originates on iliac fossa;
insertion: lesser trochanter of femur
flexes hip and rotates femur laterally, flexes vertebral column
psoas major
round muscle adjacent to iliacus;
origin: transverse process and bodies t12-L5
insertion: lesser trochanter of femur
flexes hip and rotates femur laterally, flexes vertebral column
pectineus
small muscle medial to the iliopsoas;
origin: superior ramus of pubis
insertion: lesser trochanter of femur
adducts flexes and medially rotates leg
Sartorius
runs diagonally across anterior side of thigh from ilium to medial surface of tibial
origin: anterior superior iliac spine
insertion: medial to tibial tuberosity (pes anserinus)
Flexes thigh and rotates leg laterally
tensor fascia latae
muscle located on the superior, lateral, aspect of the thigh,
origin: iliac crest and anterior superior iliac spine
inserts into the iliotibial tract;
abducts femur
iliotibial tract
fibrous band extending from iliac crest and gluteus maximus muscle down the lateral thigh to the lateral condyle of the tibial bone
Quadriceps femoris
Composed of 4 muscles: Rectus femoris, castus lateralis, vastus intermedius, vastus medialis
Rectus femoris
runs vertically on anterior side of thigh;
origin: anterior inferior iliac spine
insertion: tibial tuberosity
extends knewe, flexes thigh
vastus lateralis
runs vertically on lateral side of thigh;
origin: greater trochanter and linea aspera
insertion: tibial tuberosity
extends lower leg
vastus intermedius
directly beneath the rectus femoris;
origin: shaft of femur
insertion: tibial tuberosity
extends lower leg
vastus medialis
runs vertically on medial side of thigh;
origin: inter trochanteric line and linea aspera
insertion: tibial tuberosity
extends lower leg
gracilis
runs vertically from pubis along medial side of thigh to tibial
origin: inferior ramus and body of pubis
insertion: medial to tibial tuberosity (pes anserinus)
adducts thigh, flexes and rotates lower leg
adductor longus
most superficial adductor on medial side of the thigh;
adducts, flexes, and externally rotates lower leg
adductor brevis
small adductor between longus and magnusl
adducts, flexes, and externally rotates lower leg
adductor magnus
largest adductor on medial side of thigh;
adducts, flexes and externally rotates lower leg
gluteus maximus
largest and most superficial gluteal muscle;
origin: iliac crest, sacrum, coccyx
insertion: Gluteal tuberosity, linea aspera, and IT band
extends thigh
gluteus medius
middle gluteal muscle;
abducts and rotates thigh medially
gluteus minimus
deepest gluteal muscle; abducts thigh
Deep Hip rotators
piriformis, superior gemellus, obturator internus, inferior gemellus, obturator externus, quadratus femoris
piriformis
Deep Hip rotator
pyramidal muscle inferior to gluteus minimus;
rotates thigh laterally
superior gemellus
Deep Hip rotator
inferior to the piriformis and runs from the ischial spine to the greater trochanter
obturator internus
Deep Hip rotator
located inferior to the superior gamellus and aides in lateral rotation of the hip
inferior gemellus
Deep Hip rotator
inferior to the obturator externus and runs from the ischial tuberosity to the greater trochanter;
aids in lateral hip rotation
obturator externus
Deep Hip rotator
deep to the quadratus femoris and aides in lateral hip rotation
quadratus femoris
Deep Hip rotator
most inferior of the hip rotators
hamstrings
muscles on the posterior side of thigh
semimembranosus
hamstring most medial; origin: ischial tuberosity insertion: medial condyle of tibia flexes lower leg, extends and medially rotates leg
semitendonosus
hamstring
between the semimembranosus and biceps femoris
origin: ischial tuberosity
insertion: medial to tibial tuberosity (pes anserinus)
flexes lower leg, extends and medially rotates thigh
biceps femoris
hamstring
two-headed muscle, most lateral;
origin: ischial tuberosity and linea aspera
insertion: head of fibula
flexes lower leg, extends thigh, and medially rotates thigh
pes anserinus
bony landmark medial to the tibial tuberosity; common tendonous insertion of gracilis, sartorius, and semi tendinosus
Plantaris
small muscle in posterior side of knee;
origin: lateral supracondylar ridge of femur
insertion: calcaneus
plantar flexes foot and knee
popliteus
deep muscle in the posterior region of the knee;
origin: lateral condyle of femur
insertion: posterior surface of tibia
flexes and rotates knee
gastrocnemius
calf muscle;
origin: medial and lateral epicondyles of femur
insertion: calcaneous (calcaneal tendon)
flexes foot and knee
SOLEUS
beneath the gastrocnemius;
origin: shaft of tibia and fubula
insertion: calcaneus (calcaneal tendon)
plantar flexes foot
calcaneal tendon
tendon that connects gastrocnemius, soleus, to calcaneus bone
tibialis posterior
originates on tibia and fibula,
inserts on metatarsals;
inversion and plantar flexion of foot
flexor digitorium longus
originates on posterior surface of the tibial
inserts on phalanges;
flexes digits
flexor hallucis longus
originates on posterior side of fibula,
inserts on hallux
flexes hallux
peroneus (fibularis) longus
originates on tibia and fibula
inserts on first metatarsal;
flexes and everts foot
peroneus (fibularis) brevis
originates on distal part of fibula
inserts on fifth metatarsal;
flexes and everts foot
peroneus tertius
originates on anterior surface of fibula,
inserts on fifth metatarsal,
flexes and everts foot
extensor digitorium longus
originates on tibia and fibula,
inserts on digits 2-5 (has 4 tendons);
extends and dorsiflexes digits/foot
extensor hallucis longus
originates on fibula,
inserts on distal phalanx of hallux,
extends hallux
tibialis anterior
originates on lateral condyle of tibia,
inserts on first metatarsal
dorsiflexes and inverts foot
extensor digitorium brevis
4-part muscle deep to the tendons of the extensor digitorium longus,
originates on the calcaceus
inserts in toes 2-5;
helps extend toes 2-5
flexor hallucis brevis
medial muscle on the sole of the foot,
originates on the cuboid and lateral cuneiform
inserts on the medial and lateral sides of the great toe;
flexes great toe
abductor digiti minimi
narraow muscle on the lateral border of the sole,
originates on the calcaneus,
inserts on the lateral side of the little toe;
abducts and flexes little toe
flexor digitorium brevis
wide, superficial muscle located in the middle of the sole of the foot,
originates on the calcaneus,
inserts on toes 2-5 ;
flexes toes 2-5
abductor hallucis
lies along the medial border of the sole,
originates on the calcaneus,
inserts on the medial side of the great toe;
abducts and flexes great toe
lumbricals
four small muscles in the sole of the foot,
originates on the tendons of the flexor digitorum longus,
inserts on the tendons of the extensor digitorum longus;
extends and flexes toes 2-5
quadratus plantae
rectangular shaped muscles with two heads,
originates on the calcaneus,
inserts on the tendon of the flexor digitorum longus,
assits flexor digitorum longus in flexing toes 2-5
adductor hallucis
two-headed muscle deep to the lumbricals,
originates on metatarsals 2-4, inserts on the lateral side of the great toe;
adducts and flexes great toe
extensor hallucis brevis
muscle on top of the foot;
originates on the calcaneus,
inserts on the big toel
helps extend the great toe
flexor digiti minimi brevis
muscle lies inferior to the fifth metatarsal;
originates on the fifth metatarsal,
inserts on the lateral side of the little toe
flexes little toe
