Lecture 14 Flashcards
Function of the lower limb
• Movement and bipedal locomotion
• Weight bearing
• Force transmission
4 regions of the lower limb
Muscles of the limbs are
arranged in __________,
separated by ________
Muscles of the limbs are
arranged in compartments,
separated by fascia
Muscles in each
compartment have a
common:
• Function
• Nerve supply
• Blood supply
Pelvic girdle
Osteoligamentous ring
What bones make up the pelvic girdle
- sacrum
- hip bones
What does the pelvic girdle articulate with laterally
2 femurs
What does the pelvic girdle articulate with inferiorly
Coccyx
What does the pelvic girdle articulate with superiorly
L5 (disc and vertebral body)
What is the function of the pelvic girdle?
• Protects and supports pelvic organs
• Transfer of forces from trunk and upper limbs
• Bony prominences for attachment of muscles and ligaments
What is the function of the pelvic girdle
• Protects and supports pelvic organs
• Transfer of forces from trunk and upper limbs
• Bony prominences for attachment of muscles and ligaments
Joints of the pelvic girdle
- sarcoiliac joint X2
- pubic symphysis
What are the three fused hip bones and when do they fuse
• Ilium
• Ischium
• Pubis
(fuse in late teens, 16–18 years)
Where do the 3 hipbones join
Join at the acetabulum = socket for the head of the femur
What attaches to the ischial tuberosity
Hamstrings
What do the hamstrings flex / extend
• Extend thigh
• Flex knee
What ligaments attach here
What covers the Obturator foramen
obturator membrane
What passes through the obturator foramen
• Obturator nerve and vessels pass through it
What is the obturator membrane made of
DFCT
What ligament attaches between these two points?
Inguinal ligament
What’s near the inguinal ligament?
• Inguinal canal – superior to the inguinal ligament.
Relevance to inguinal hernia.
• Femoral artery – deep to the inguinal ligament. Location
for catheterisation.
Articular surfaces of sacrum
What kind of joints are Sacroiliac joints (SIJs
• Synovial and fibrous joint
complex
Function of Synovial and fibrous joint
complex
• Stress-relieving ie., transmit
loads but allow for slight ‘give’
• Function is a reflection of bony
congruency and ligamentous
support
What ligaments stabilise the SIJ? - primary
Interosseous is the strongest and thickest
What ligaments stabilise the SIJ? - secondary
Sacrospinous & sacrotuberous ligaments (secondary) function
• Resist rotation of sacrum between hip bones
• Form boundaries of greater and lesser sciatic foramina
What forms the boundaries of the greater and lesser sciatic foramina
Sacrospinous & sacrotuberous ligaments
What structures exit through the greater sciatic foramen?
• Piriformis muscle
• Superior and inferior gluteal
nerves (supply the gluteal muscles)
and associated blood vessels
• Sciatic nerve (supplies posterior
muscles of the thigh, all leg and
foot muscles)
Sciatic nerve
What does the sciatic nerve supply?
supplies posterior
muscles of the thigh, all leg and
foot muscles
What kind of joint is the public symphysis
Cartilaginous joint
Features of the pubic symphysis
• Pubic bones x 2
• Interpubic disc (made of fibrocartilage)
• Stabilised by ligaments and surrounding muscles (especially the adductors)
Function of pubic symphysis
- to allow for a little bit of give
- SHOCK ABSORBTION
Angle of inclination of femur =
125
What is functional significance of the 125 degree inclination of the femur
- pelvis is wider then our feet so we need the angle to compensate for the width of the pelvis
What muscles attach to the greater trochanter?
Hip abductor muscles
What muscles attach to the lesser trochanter?
- hip flexor muscles such as the iliopsoas
3 different fracture locations of the femur
- transcervical fracture of femoral neck
- spiral fracture
- intertrochanteric fracture
What kind of joint is the hip joint
• Synovial, ball and socket joint
• Multiaxial
Bony component of the hip joint
− Acetabulum
− Head of femur
Functions of the hip joint
- links lower limb to pelvis
- stability > mobility
- weight-bearing
Features of the hip joint joint capsule
• Joint capsule (two layers):
– Outer, fibrous layer
– Inner, synovial membrane (reduces friction)
• Attaches around margin of acetabulum and to femoral neck
• Reinforced by ligaments
Hip joint capsular ligament are difficult to …
distinguish from capsule
Functions of the capsular ligaments
• All ligaments are tight with hip extension
(e.g., in standing)
• This position is energy efficient
(don’t need to rely on muscles for support)
Three main capsular ligaments of the hip joint
• Iliofemoral (Y-shaped, strongest)
• Ischiofemoral
• Pubofemoral
Ligaments are not linear and therefore as well as maintaining extention, they prevent rotation
What is the labrum
- contributes to stability
- it is fibrocartilage that attaches to the rim of the acetabulum
