LL1 - Osteology, joints and ligaments of the hip, thigh and knee

Question 1

how many bones constitute the pelvic girdle - list them

Answer 1

4 bones - sacrum, coccyx, and the right & left hip bones

Question 2

what are the functions of the bony pelvis? (4)

Answer 2

1. transmits the body’s weight from the vertebral column to the femur
2. contains, protects, & supports the pelvic organs – distal end of the GI tract & reproductive organs
3. provides attachment for the lower limbs & trunk
4. anchors the roots of external genitalia

Question 3

list the 4 main joints of the pelvic girdle - how are they each formed (articulations)?

Answer 3

sacroiliac joint - between the sacrum & ilium

lumbosacral joint - between the 5th lumbar vertebrae & sacrum

sacrococcygeal joint - between the sacrum & coccyx

pubic symphysis - secondary cartilaginous joint formed between the right & left hip bones

Question 4

function of the pelvic symphysis?

Answer 4

as a secondary cartilaginous joint - can soften and stretch during pregnancy, causing pain

Question 5

function of the sacroiliac joint?

Answer 5

transfers weight from the sacrum to hip bones (to lower limbs) - has a weight-bearing function

Question 6

the hip bone consists of three bones - list them. what do they come together to form, and what is the significance of this structure?

Answer 6

ilium, ischium, pubis - fuse together to form the (rounded) acetabulum

significance: rounded head of femur sits in the acetabulum = forms the hip joint

Question 7

why is the ischial tuberosity flared?

Answer 7

it’s flared due to the pressure of us sitting on it

Question 8

what structures form the boundaries of the obturator foramen?

Answer 8

superior pubic ramus & ischiopubic ramus form the (bony) boundaries

obturator membrane reduces the size of the obturator foramen - allows neurovascular bundle to pass through a smaller foramen

Question 9

which ligament converts the greater sciatic notch into the greater sciatic foramen? what structures does this ligament run between?

Answer 9

sacrospinous ligament - runs between the ischial spine & lateral borders of sacrum and coccyx

Question 10

which ligament converts the lesser sciatic notch into the lesser sciatic foramen? what structures does this ligament run between?

Answer 10

sacrotuberous ligament - runs between the ischial tuberosity & lateral borders of the sacrum and coccyx

Question 11

what structures pass through the greater sciatic notch?

Answer 11

sciatic nerve
piriformis muscle

Question 12

what structures pass through the lesser sciatic notch?

Answer 12

pudendal nerve
internal pudendal vessels
- pass between the pelvic cavity, perineum, and gluteal region

Question 13

function of the acetabulum? what structure within it contributes to hip joint stability & how?

Answer 13

acetabulum is a deep socket that articulates with the rounded head of the femur

acetabular labrum contributes to hip joint stability by further deepening the socket, also reducing its mobility

Question 14

which lower limb structure is commonly fractured in individuals with osteoporosis?

Answer 14

neck of femur - narrowed region that connects the femoral head to the greater & lesser trochanters

Question 15

what is the significance of the fovea of the femur?

Answer 15

attachment point for the ligament of the head of the femur (ligamentum teres)

Question 16

where does the quadratus femoris insert on the femur?

Answer 16

on the quadrate tubercle - posterior aspect of the proximal femur

Question 17

where does the iliopsoas tendon insert on the femur?

Answer 17

on the lesser trochanter

Question 18

what is the significance of the trochanteric fossa on the femur?

Answer 18

it’s where some lateral rotator muscles insert - e.g. the gemelli muscles, obturator internus and externus

Question 19

function of the gluteal tuberosity on the femur?

Answer 19

on the lateral aspect of the femur - insertion point for the gluteus maximus muscle

it extends down and forms the linea aspera (ridge)

Question 20

where do some lateral rotator muscles insert on the proximal femur?

Answer 20

trochanteric fossa

Question 21

compare the anterior & posterior surfaces of the proximal femur

Answer 21

anterior surface is relatively smooth and featureless

posterior surface has many features; many of these features are muscle insertion sites:
- gluteal tuberosity
- quadrate tubercle
- trochanteric fossa
- medial & lateral lips of the linea aspera
- intertrochanteric crest