week 11 - myo of the pelvis and thigh Flashcards
5 myo of adductor group
- adductor magnus
- adductor longus
- adductor brevis
- pectineus
- gracilis
adductors – general location
- medial thigh between hamstrings + quadriceps femoris myo
- all are posterior to quadriceps femoris group except the gracilis
- attach either superior or inferior ramus of pubis to part of the femur (except gracilis, which crosses knee + attaches to tibia)
actions of the adductors
- adduct the hip
- medially rotate the hip
- flex the hip (all, except gracilis)
nerves of the adductors
- ALL: obturator nerve
- PECTINEUS: obturator + femoral nerves
adductor magnus – nickname
- “floor of the adductors” bc of broad span
- most posterior of the adductors
adductor magnus – origin
- inferior ramus of pubis
- ramus of ischium
- ischial tuberosity
adductor magnus – insertion
- medial lip of linea aspera
- adductor tubercle
adductor magnus – actions
- adduct hip
- medially rotate hip
- extend hip (posteror fibers of adductor magnus only)
adductor magnus – nerve
- obturator nerve
adductor longus – origin
pubic tubercle
adductor longus – insertion
medial lip of linea aspera
adductor longus – actions
- adduct hip
- medially rotate hip
adductor longus – nerve
obturator nerve
adductor brevis – origin
inferior ramus of pubis
adductor brevis – insertion
- pectineal line of femur
- medial lip of linea aspera
adductor brevis – actions
- adduct hip
- medially rotate hip
adductor brevis – nerve
obturator nerve
pectineus – origin
superior ramus of pubis
pectineus – insertion
pectineal line of femur
pectineus – actions
- adduct hip
- medially rotate hip
pectineus – nerve
obturator + femoral nerves *
gracilis – origin
inferior ramus of pubis
gracilis – insertion
pes anserinus tendon
gracilis – actions
- adduct hip
- medially rotate hip
- flex knee * (bc it crosses over knee joint)
- medially rotate flexed knee *
gracilis – nerve
obturator nerve
tensor fascia latae (TFL) – location
- small, superficial myo about 3 finger widths wide
- located on lateral side of upper thigh
- accessible bw upper fibers of rectus femoris + gluteus medius
- attaches to IT band along w glute max
iliotibial tract – location
- superficial sheet of fascia w vertical fibers (NOT a muscle)
- runs along lateral thigh from hip to outer knee (tibial tubercle)
- TFL and glute max attach here
iliotibial tract – function
- strong, stabilizing structure for hip and knee
- like spandex for the thighs (has thick, matted texture that is similar to packing tape)
tensor fascia latae (TFL) – origin
iliac crest
tensor fascia latae (TFL) – insertion
ilitiotibial tract (IT band)
tensor fascia latae (TFL) – actions
- flex hip
- medially rotate hip
- abduct hip
tensor fascia latae (TFL) – nerve
superior gluteal nerve
sartorius – unique qualities
- aka tailor’s muscle (“sartor” = tailor)
- aka longest muscle i the body
sartorius – origin
ASIS
sartorius – insertion
pes anserinus tendon (medial knee)
sartorius – actions
- flex hip
- laterally rotate hip
- abduct hip
- flex knee
- medially rotate knee
sartorius – nerve
femoral nerve
3 tendons of medial posterior knee
medial to lateral, and merging to form pes anserinus tendon:
- sartorius
- gracilis
- semitendinosus
2 tendons of lateral posterior knee
medial to lateral:
- biceps femoris
- iliotibial tract
6 lateral rotators of hip
- piriformis
- quadratus femoris
- obturator internus
- obturator externus
- gemellus superior
- gemellus inferior
general location of lateral rotators
- located deep to glute max
- attach to aspects of greater trochanter; fan medially to attach to sacrum + pelvis
actions of lateral rotators
- laterally rotate hip (ALL)
- abduct hip when it is flexed (piriformis only)
piriformis – origin
anterior surface of sacrum
piriformis – insertion
superior aspect of greather trochanter
piriformis – actions
- laterally rotate hip
- abduct hip when hip is flexed
piriformis – nerve
sacral plexus nerve
piriformis syndrome
- piriformis is the only of the lateral rotators that lies superficial to the sciatic nerve and, if overcontracted, can compress it, leading to “piriformis syndrome”
- piriformis syndrome (an impinged sciatic nerve due to tight or spasmy piriformis) is NOT the same as “true sciatica”, which is in the low back
- however, what some people mistakenly call “sciatica” is really a symptom of piriformis syndrome (so impt to distinguish bw them)
true sciatica vs. piriformis syndrome
look at their gait:
- if they’re bent over slightly and have dull achey pain in low back, it’s true sciatica
- if they have sharp shooting pain while walking and their leg is extended during “heel strike”, then it’s piriformis syndrome
2 iliopsoas myo
- psoas major
2. iliacus
iliopsoas – actions + function
flex hip + stabilize low back via these actions:
- flex hip (w origin fixed)
- flex trunk toward thigh + tilt pevis anteriorly (w insertion fixed)
iliopsoas – general location
- psoas major is located deep to abdominal contents; stretches from lumbar vertebrae, underneath inguinal ligament, to lesser trochanter
- iliacus is stockier; located deep to abdomen in iliac fossa; joins with psoas major at lesser trochanter
psoas major – unique qualities
- aka “the great hip flexor”
- known as the “tenderloin” or “filet minon”
psoas major – origin
bodies + TVP’s of lumbar vertabrae
psoas major – insertion
lesser trochanter of femur
psoas major – nerve
lumbar plexus nerve
iliacus – origin
iliac fossa
iliacus – insertion
lesser trochanter of femur
iliacus – nerve
femoral nerve
testing the iliopsoas
version 1 – have them lie prone. bend knee, take heel to butt. if butt lifts, then tight iliopsoas.
version 2 – while seated, bend knee and lift it toward hip. press down on their knee and have them resist.
sacrotuberous ligament – location
- attaches edge of sacrum to ischial tuberosity
- deep to glute max
sacrotuberous ligament – function
- stabilizes sacrum
- tightness on one side can angle sacrum to one side
inguinal ligament – location
attaches ASIS to pubic tubercle
inguinal ligament – function
- forms superior border of femoral triangle + lower edge of abdominal aponeurosis
- protects the vessels (nerves, arteries, veins, and lymph nodes) that are underneath, at the femoral triangle
3 sides of femoral triangle
- inguinal ligament
- sartorius
- adductor longus
vessels of the femoral triangle
anterior right hip, lateral to medial: NAVL
- NERVE: femoral nerve
- ARTERY: femoral artery
- VEIN: femoral vein
- LYMPH: inguinal lymph nodes
inguinal hernia
- more common in men
- instestines can push through the inguinal ligament
round ligament – AKA
- “ligamentum teres”
- “ligamentum capitis femoris”
round ligament – location
attaches center of acetabulum (inside labrum) to fovea of head of femur
round ligament – function
stabilizes hip socket
warning: doing side-to-side splits could over stretch and harm the round ligament
sciatic nerve – location
- largest nerve in body (~3/4 inch diameter)
- formed by spinal nerves of L-4 thru S-3
- passes through greater sciatic notch, bw ischial tuberosity + greater trochanter, and extends down posterior thigh
sciatic nerve – function
bc it runs deep to piriformis, can become compressed or entrapped (piriformis syndrome)
trochanteric bursa – location
along posterior/lateral aspect of greather trochanter
trochanteric bursa – function
- reduces friction bw trochanter and glute max
- can be distended or inflamed due to wearing low-rider jeans that are too tight
