bones and muscles of pelvis and thigh 1 Flashcards
3 parts of pelvis
- sacrum
- coccyx
- two hip bones
3 parts of hip bone
- ilium
- ischium
- pubis
female vs. male pelvis
female pelvis is broader for carrying + delivering child:
- wider iliac crest
- larger pelvic “bowl”
- greater distance b/w ischial tuberosities
pubis – bony landmarks
- superior ramus of pubis
- inferior ramus of pubis
- pectineal line
- pubic tubercles (L+R join at pubic crest)
- symphyseal surfaces (L+R join at pubic symphysis)
- pubic symphysis
ischium – bony landmarks
- ischial tuberosity (“sitting bones”)
- ramus of iscium (no superior + inferior ramus like on the pubis)
- lesser sciatic notch
- ischial spine (b/w greater + lesser sciatic notch)
ilium – bony landmarks
- iliac crest (b/w ASIS + PSIS)
- iliac tubercle (approx. 2 inches posterior to ASIS on the iliac crest)
- anterior superior iliac spine (ASIS)
- anterior inferior iliac spine (AIIS)
- posterior superior iliac spine (PSIS)
- posterior inferior iliac spine (PIIS)
- greater sciatic notch
- obturator foramen (big hole)
medial ilium (inside) – bony landmarks
- iliac fossa (the “bowl” part inside)
- articular suface for sacrum (“boot-shaped”)
lateral ilium (outside) – bony landmarks
- anterior gluteal line
- posterior gluteal line
- inferior gluteal line
- acetabulum (socket where femur articulates)
- lunate surface of acetabulum (croissant-shaped)
“butt dimples” – location
PSIS
sockets for femur – name + location
acetabulum, located on lateral side of hip bone
ischial tuberosity – AKA
“sitting bones”
hip joint – official name
coxal joint (ball-and socket)
sacrum and coccyx – # of fused vertebrae
- 4 or 5 fused vertebrae in sacrum
- 3 or 4 fused bones in coccyx
sacrum – bony landmarks
- median sacral crest (where spinous processes are located)
- lateral sacral crest (remnants of TVP’s, one on each side of median sacral crest)
- posterior sacral foramen (holes on eather side of median sacral crest, as seen from back)
- anterior sacral foramen (holes seen from front of body)
- transverse ridges (remnants of intervertebral discs of sacral vert., visible from anterior sacrum)
- sacral promontory
femur – proximal bony landmarks
- head, neck
- fovea of head (site of nerve, artery + ligament entry/exit for head of femur)
- greater trochanter
- lesser trochanter
- intertrochanteric line (anterior, b/w greater + lesser trochanter)
- intertrochanteric crest (posterior)
- trochanteric fossa (more accessible from posterior)
- gluteal tuberosity (distal to posterior surface of greater trochanter)
- pectineal line (distal to posterior surface of lesser trochanter)
femur – bony landmarks of shaft
- shaft
- medial lip of linea aspera
- lateral lip of linea aspera
“linea” = line; “aspera” = rough
femur – distal bony landmarks
- patellar surface (anterior)
- medial condyle / lateral condyle
- medial epicondyle / lateral epicondyle
- medial supracondylar line / lateral supracondylar line
- adductor tubercle (medial side, superior to medial epicondyle)
- intercondylar fossa (posterior, b/w two condyles) (“knee pit”)
femur – how to tell L + R
- knobby condyles are behind the knee
- they stick out of back/posterior
patella articulates with…
femur only
tibia vs. fibula
- fibula is thinnest bone in proportion to length
- fibula is lateral to tibia (think “fibulateral”)
- tibia = medial malleolus
- fibula = lateral malleolus
tibia – proximal bony landmarks
- lateral condyle / medial condyle (at knee)
- intercondylar tubercles (attachment site for cruciate ligaments)
- tibial tuberosity (anterior; attachment for quads)
- pes anserinus (medial to tibial tuberosity; attachment for myo)
- groove for insertion of semimembranosus tendon (posterior) **
- soleal line (for soleus myo)
- shaft
tibia – distal bony landmarks
- medial malleolus (inner ankle bone)
- fibular groove of tibia
fibula – bony landmarks
(bottom more flat; top more bulbous)
- lateral malleolus (outer ankle bone)
- head
- shaft
patella – bony landmarks
- base (proximal)
- apex (distal)
4 myo in quadriceps femoris group
- rectus femoris (central, superficial, crosses 2 joints)
- vastus medialis (medial)
- vastus lateralis (lateral)
- vastus intermedius (deep to rectus femoris)
quadriceps femoris – origins
- rectus femoris: AIIS
- vastus medialis: medial lip of linea aspera
- vastus lateralis: lateral lip of linea aspera, gluteal tuberosity + greater trochanter
- vastus intermedius: anterior + lateral shaft of femur
quadriceps femoris – insertion
- tibial tuberosity (via the patella and patellar ligament)
- (all four quad myos converge into a single tendon above knee; that tendon connects to the top and sides of patella before attaching to tibial tuberosity via the patellar ligament)
- (because the tendon attaches one bone to another – the patella to the tibia – it is actually considered a ligament)
quadriceps femoris – actions
- ALL: extend knee
- rectus femorus only: flex the hip
quadriceps femoris – nerve
femoral nerve
osgood schlatter’s disease
- avulsion fracture of the tibial tuberosity (avulsion fracture is when myo pulls a piece of bone with it when the bone fractures)
- pulls tibial tuberosity away from tibia (common in kids bc their bones are softer and not fully ossified)
4 hamstrings myo
- biceps femoris (long head + short head)
- semitendinosus (superficial to the semimembranosus)
- semimembranosus (wider and deeper than semitendinosus)
hamstrings – common origin
ischial tuberosity (for all except the short head of biceps femoris)
biceps femoris – origin
- ischial tuberosity (long head)
- lateral lip of linea aspera, on shaft of femur (short head)
biceps femoris – insertion
head of fibula
biceps femoris – action
- flex knee
- laterally rotate flexed knee
- extend hip (long head only)
biceps femoris – nerve
sciatic nerve (largest nerve of body girth-wise)
semitendinosus – origin
ischial tuberosity
semitendinosus – insertion
pes anserinus tendon
conjoined tendons of 3 myo including sartorius, gracilis, and semitendinosus, at proximal medial shaft of tibia
semitendinosus – actions
same actions as semimembranosus:
- flex knee
- medially rotate flexed knee
- extend hip
- tilt pelvis posteriorly
semitendinosus – nerve
sciatic nerve (largest nerve of body girth-wise)
semimembranosus – origin
ischial tuberosity
semimembranosus – insertion
medial condyle of tibia (posterior aspect)
semimembranosus – actions
same actions as semitendinosus:
- flex knee
- medially rotate flexed knee
- extend hip
- tilt pelvis posteriorly
semimembranosus – nerve
sciatic nerve (largest nerve of body girth-wise)
3 gluteal myos
- gluteus maximus
- gluteus medius
- gluteaus minimus
gluteal myos – general function
strong extensors and abductors of hip
gluteus maximus – origin
- coccyx
- edge of sacrum
- posterior iliac crest
gluteus maximus – insertion
- iliotibial tract
- gluteal tuberosity
gluteus maximus – actions
- extend hip
- laterally rotate hip
- abduct hip
- adduct hip (lower fibers only)
gluteus medius – AKA
- “deltoid myo of the hip joint”
- has anterior and posterior fibers
gluteus medius – origin
gluteal surface of ilium
gluteus medius – insert
neck of femur / lateral aspect of greater trochanter
gluteus medius – actions
- ALL fibers: abduct hip
- anterior fibers: flex, medially rotate hip
- posterior fibers: extend, laterally rotate hip
gluteus minimus – origin
gluteal surface of ilium (deep to gluteus medius)
gluteus minimus – insertion
greater trochanter
gluteus minimus – actions
- abduct hip
- medially rotate hip
- flex hip
iliotibial tract (IT band)
- a fibrous band; site for myo attachments
- attached to 2 myo in pelvis: gluteus maximus + TFL
- IT band keeps thigh myo pressed together and compacted (like spandex)
gluteal myos – nerves
kind of backwards:
- inferior gluteal nerve (gluteus maximus)
- superior gluteal nerve (gluteus medius + minimus)
