Hip

Question 1

what does the pelvic girdle do

Answer 1

• Forms a stable ring

- Foundation of the lower limb

Question 2

what is the pelvic girdle formed of

Answer 2

• Ischium – sit on the ischium tuberosities
• Ileum
• Pubis

Question 3

where do the ischium, ileum, and pubci meet

Answer 3

• acetabulum

Question 4

what is the difference in the acetabulum of children versus adults

Answer 4

there is an epipsymphial joint in children therefore allows for more movement
- don’t have much movement in adult skeleton therefore forms a nice foundation to have a stable base for the lower limb

Question 5

what does the sacroiliac joint do

Answer 5

• Connects ileum to the sacrum

Question 6

what does the pubic symphysis do

Answer 6

• Connects hemi-pelvis anteriorly

Question 7

what kind of joint is the hip

Answer 7

• Ball and socket synovial joint

Question 8

what is the hip designed for in comparison to the glenohumeral joint

Answer 8

• Designed for stability whereas the glenohumeral joint is designed for motility

Question 9

what does the acetabular do

Answer 9

cup shape and covers all of the femoral head

Question 10

why is the hip stable

Answer 10

• there is deep insertion of the femoral head into the acetabulum
• there is a strong tight articular capsule that extend to the femoral neck this limits movement
• ligaments are around the joint capsules - ligament teres
• power muscles that are tonically active
• fat pads fills central region and adds cushioning for thinnest part of acetabulum, this is where the acetabulum might break - pushes femur head into the acetabulum without damaging it
• acetabular labrum is not complete in the hip joint but adds 10% surface area

Question 11

why is the ligament teres important in children

Answer 11

in adults don’t really need it but in children they might not have the same articulalation and this stops the separation of the head of the femur

Question 12

what happens when you stand up and sit down to the ligaments in the hip

Answer 12

– When hip extended (for example when you stand up)ligament fibres become twisted and tighten (shorten) articular capsule pulling acetabulum and femur together\
– When hip sat down and flexed the ligament fibres are horizonal and looser, prevent the articular capsule from tearing

Question 13

what rotators push he femur into the acetabulum

Answer 13

• Medial and lateral rotators reciprocal pull, they both pull from the anterior and posterior side and these pull the head of the femur deeper into the acetabulum

Question 14

describe the structure of the acetabular

Answer 14

• fibrocartilage

- horse shoe ring - therefore it is incomplete

Question 15

why is the acetabular incomplete

Answer 15

– Have a horseshow rather than a complete ring because the Blood vessels that pass into joint through notch and via ligament of head of femur – there is blood vessel running down the centre of the ligament of the head of the femur

Question 16

what parts of the femur are in the articular capsules

Answer 16

• Anterior surface and medial half of posterior surface of the femoral neck

Question 17

where are the articular capsule and ligaments at there thickest

Answer 17

• Strongest and thickest over upper and anterior parts, thinner over lower and posterior parts

Question 18

what do the ligaments do to the articular capulse

Answer 18

• Ligaments around joint blend with articular capsule, strengthening it further

Question 19

what ligament is the strongest

Answer 19

• Anterior Iliofemoral ligament strongest – runs along the front of the joint capsule

Question 20

what does the anterior Lilofemoral ligament do

Answer 20

• Prevent excessive extension of the hip – this is because it becomes tight and taut it prevents you over extending the hip
• Relaxed in flexion
• When it becomes taut in extension it pulls the head of the femur in the acetabulum

Question 21

why are the posterior ligaments weaker

Answer 21

• This is because the do not cover the whole of the femoral neck, doesn’t need to become all the way back because there is a big muscle

Question 22

where is the hip most likely to disclose

Answer 22

• posteriorly due to lack of ligaments

- Often happens with acetabulum fractures as well, this is with chips breaking off the posterior rim

Question 23

what happens during a posterior dislocation

Answer 23

• The head of the femur goes behind the pelvis so the leg is shortened and medially rotated

Question 24

what is affected in a hip disocloation

Answer 24

• blood vessels are all anterior to the joint so therefore they are not effected
• sciatica nerve is posterior therefore is more likely to be effected
• Discloation can compress or stretch the sciatic nerve

Question 25

what is the sciatic nerve

Answer 25

- biggest nerve in the body | - it innervates the hamstrings and everything below the knee

Question 26

what does the femoral nerve innervate

Answer 26

the quadriceps

Question 27

what are the hip flexors and what is its innervation

Answer 27

- Innervation = femoral nerve - Iliopsoas (it is made by these muscles iliacus and psoas major, attaches to the lesser tronchater) - Sartorius assist flexion - Pectineus assist flexion – Quadriceps (rectus femoris)

Question 28

what does sartoirus also do

Answer 28

abducts and laterally rotates hip

Question 29

what does pectineous also do

Answer 29

adducts and medially rotates

Question 30

what does psoas minor do

Answer 30

– Helps stabilise psoas major

Question 31

what are the main hip abductors

Answer 31

– Gluteus medius | – Gluteus minimus

Question 32

what are the muscles that make up the gluteus muscle group

Answer 32

– There are 3 muscles in the gluteus muscle group these are gluteus medius, minimus and maximus

Question 33

what muscles cause lateral rotation

Answer 33

– Piriformis – this comes from the sacrum, goes from the sciatic notch and onto the back of the greater tronchater

Question 34

what muscles do hip enxteion

Answer 34

- Gluteus maximus (basically does all of extension on its own) – helps lift the limb up, comes from the sacroiliac joint up to the iliac crest, inserts into the greater trochanter - It is assisted by the hamstrings, work as a functional group, these are the hamstring group and these assist in hip extension

Question 35

what nerve innervates hip extension

Answer 35

inferior gluteal nerve | - - innervation by tibial division of sciatic

Question 36

what nerves and muscles do hip adbuction

Answer 36

``` o gluteus medius and minimus  Innervation = superior gluteal nerve o Tensor fasciae lata  Innervation superior gluteal nerve  This also helps gluteal maximus to tense ilotibial tract ```

Question 37

where does the iliotibial tract come from

Answer 37

- Comes from the iliac crest to the tibia

Question 38

what does the iliotibial tract do

Answer 38

- When it tightens all the muscles get pushed towards the femur - Stops the muscles on the lateral side of the leg pressing out and pushing agains the skin, pushes them against the femur - Stablisie the knee and hip join

Question 39

describe the structure of the iliotibial tract

Answer 39

- Acts as a long aponeurosis (tendon sheet) inserting into the iliotibial tract is the tensor fasciae latae and superficial and anterior parts of gluteus maximus - thickening of the deep fascia but acts like a tendon

Question 40

what is the muscles and innervation of hip adduction

Answer 40

- This is the adductor group of muscles medial thigh adductor longus, brevis and magnus, gracilis, pectineus and obturator externus - Innervation = obturator nerve

Question 41

what muscles do hip lateral rotation

Answer 41

- Gluteus maximus | - Adductor group

Question 42

what muscles do hip medial rotation

Answer 42

- Gluteus medius/minimus | - Tensor fasciae latae

Question 43

muscles overlap ...

Answer 43

- Muscels overlap depending on what they do, so adductors can also be flexors - For example gluteus medium and minimus do abductors and medial rotators

Question 44

where do hip fractures occur

Answer 44

– High in femoral neck, subcapital – Across the neck, cervical – Trochanteric region – Pretrochanteric

Question 45

what is the symptoms of hip fractures

Answer 45

- Shortening of the leg - Lateral external rotation - Shentons line is disrupted by the fracture – shentons line is always disrupted good way to diagnose this

Question 46

what is the treatments of hip fractures

Answer 46

- Depends on the age of the individual and the shape of the bone pelvis - For young people – pinned and this is healed in 6 months and then you can remove the screws in older - Usually linked to osteoporosis - Use screws and total hip replacement

Question 47

what re the complications of hip fractures

Answer 47

- Fracture to the neck of the femur may disrupt blood supply to the femoral head – avascular necrosis - The blood supply comes in more distally and moves proximally up to the head therefore if you fracture the neck you disrupt this blood supply - Femoral head becomes avascular and dies - The circumflex branches can get broken - There is collapse of the bone, loss of rounded profile and loss of surface of the joint, the bone cracks and collaspes - Articular cartilage separates so you get a gap and the pressure causes it to collaspse and break

Question 48

why is the hip prone to developing osteoarthritis

Answer 48

- Carry’s the weight of the body therefore it is more prone developing osteoarthritis - If you lose it then you expose the bone