8. Lower Limb Flashcards
(126 cards)
What is the pelvic girdle?
- The pelvic (hip) girdle is formed from two hip bones, known as the os coxae.
- At birth, each hipbone is composed of three separate bones which fuse together, called the ilium, ischium and pubis.
- The pelvic girdle directly articulates with the vertebral column at the sacroiliac joints.

What does the pelvic girdle articulate with?
- Medially -> With sacrum at sacroiliac joint
- Laterally -> With femur at acetabulum
What bones make up the hip bone? What is the position of each?
- Ilium -> Top
- Ischium -> Bottom, Back
- Pubis -> Bottom, Front

What are the main landmarks of the hip bone?
Ilium:
- Iliac crest (palpable)
- Anterior superior iliac spine (ASIS) (palpable)
- Posterior superior iliac spine (PSIS) (palpable)
- Anterior inferior iliac spine (AIIS)
- Greater sciatic notch
Ischium:
- Ischial spine
- Ischial tuberosity (palpable)
Pubis:
- Pubic tubercle (palpable)
All 3:
- Acetabulum -> Articulates with head of femur
Describe the joint type and movement at the sacroilial joint.
- Synovial
- But any movement is almost entirely prevented by strong ligaments and interlocking articular cartilage.
What ligaments at the sacroiliac joint do you need to know about?
- Intrinsic
- Sacrotuberous
- Sacroiliac
Give a summary of the ligaments at the sacroiliac joint.
- Sacroiliac ligament
- Anterior sacroiliac ligament -> From the ala of the ilium to pelvic surface of
- Posterior sacroiliac ligament -> Similar to anterior counterpart, except on the posterior side
- Sacrotuberous ligament -> From inferior sacrum to iliac tuberosities
- Sacrospinous ligament -> From lateral sacrum to ischial spine
- Intrinsic ligaments

Draw the position of the anterior sacroiliac ligament.

Draw the position of the posterior sacroiliac ligament, sacrospinous ligament and sacrotuberous ligament.

What bones form the acetabulum?
The three bones of the hip, the pubis, ilium and ischium
What is the acetabular labrum?
A ring of fibrocartilage that deepens the acetabulum socket, attaches to the transverse acetabular ligament
What is the femoral head lined with?
Hyaline cartilage, except for a section which attaches to the femoral head ligament
Describe the joint capsule of the hip joint.
Capsule passes from the rim of the acetabulum to the intertrochanteric line of the anterior femur, and reflects to the midpoint of the femoral neck posteriorly.
Compare the shoulder and pelvic girdles.
Shoulder girdle:
- Does not directly articulate with the vertebral column
- Shallow sockets to maximise movement
- Adapted to offer more movement than strength
Pelvic girdle:
- Directly articulates with the vertebral column, at the sacroiliac joints
- Deep sockets, maximising stability but restricting mobility
- Adapted to offer more strength than movement
What ligaments stabilise the hip joint?
- Iliofemoral ligament
- Pubofemoral ligament
- Ischiofemoral ligament
- Transverse ligament
- Ligamentum teres
So just remember that each of the hip bone component bones has a ligament to the femur.
Draw the transverse acetabular ligament.

What is the ligamentum teres in the hip?
A ligament between the head of femur to the acetabular notch.

Describe the blood supply to the head of femur.
Medial and lateral femoral circumflex arteries create the trochanteric anastamosis around the femoral neck.
What are the main hip flexors?
- Iliacus -> From iliac fossa to tendon of psoas
- Psoas major -> From lumbar vertebrae and intervertebral discs to the lesser trochanter of the femur
Extra ones you don’t need to know:
- Pectineus
- Rectus femoris
What is a secondary function of the psoas major apart from hip flexion?
Flexion of the lumbar spine
What are the main hip extensors? What is the innervation?
- Hamstrings
- Gluteus maximus (at extremes) -> Posterior ilium, sacrum and coccyx to femur and iliotibial tract
Innervation: Sciatic nerve (hamstrings), Inferior gluteal nerve (gluteus maximus)
What are the hamstring muscles? Where do they attach?
- Origin: Tuberosity of ischium
- Insertions: Tibia (semitendinosus and semimembranosus) and fibula (biceps femoris)







