Hip Conditions

Question 1

What is antalgic gait? Caused by?

Answer 1

Pt has short stance phase on affected leg (spends little time on that leg). Caused by pain in the leg/hip on affected side.

Question 2

What is trendelenburg gait?

Answer 2

Sound side of the hip sags when walking. Caused by weakness of the contralateral hip abductors (gluteus medius).

Question 3

What is festinant gait and when do you see it?

Answer 3

Short, shuffling steps
Seen in parkinsons

Question 4

What is high steppage gait and what is it caused by?

Answer 4

Patient lifts up leg to walk, foot lands flat or on ball of foot.

Caused by foot drop (common peroneal nerve palsy) or propioception loss

Question 5

What is spastic gait?

Answer 5

Jerky, foot in quinus, hips abducted. Caused by UMN lesion

Question 6

What causes true limb shortening?

Answer 6

1) Distal to trochanter: old tibia/femur fracture, growth disturbances
2) Proximal to trochanter: Hip dislocation, coxa vara, Perthes’ disease

Question 7

What is coxa vara?

Answer 7

Angle between femoral neck & femoral shaft <120deg.

Question 8

What is Perthes’ disease?

Answer 8

Necrosis and fracture of femoral head due to interruption of blood supply to the femoral head

Question 9

What are some risk factors for avascular necrosis of the hip?

Answer 9

1) Steroids, TCM
2) Trauma (NOF #, dislocation, septic arthritis)
3) Alcohol, obesity
4) Diving - decompression sickness
5) sickle cell anaemia, clotting disorders (thrombophilia)

Question 10

Clinical presentation of AVN

Answer 10

Joint pain w stiffness - exacerbated by weight bearing & motion

Rest pain in 2/3, night pain in 1/3

Restricted ROM (*ESPECIALLY INTERNAL ROTATION)

80% AVN is bilateral

Question 11

___ staging for AVN

Answer 11

Ficat-Arlet Staging

• Stage 0: hip at risk
• Stage 1: pain in groin. no structural failure but have bone death (MRI shows edema)
• Stage 2: pain + stiffness. early structural failure + repair by laying new bone (sclerosis)
• Stage 3: pain + stiffness + limping. major structural change w crumbling of necrotic bone, distorted outline. femoral head flattened.
• Stage 4: very painful, stiffness, limping. articular cartilage destruction + secondary OA. Femoral head & articular surfaces collapse, LIMB SHORTENS

Question 12

Aetiologies of OA Hip

Answer 12

1) Primary: small/bumpy femoral head, thick femoral neck = more contact bw femoral head & acetabulum (asian hips less common this shape)

2) Secondary: AVN, acetabular dysplasia (shallow), post-trauma, post-infection, crystal arthropathy

Question 13

RA hip Xray findings

Answer 13

Minimal findings initially -> synovitis usually causes pain at presentation, not evident on XR. Progressive hyaline cartilage destruction eventually causes joint space narrowing.

Question 14

Types of pelvic fractures (Tile classification)

Answer 14

Type A: stable, minimally displaced - avulsion fractures/fracture not involving pelvic ring

Type B: partially unstable, rotationally unstable, vertically stable. “open book” fractures. (rotational force)

Type C: unstable, rotationally+vertically unstable. Rupture of ipsilateral ligament. (vertical shear fracture)

Question 15

Impt complication of pelvic fractures

Answer 15

Haemorrhage - life threatening, can accumulate up to 4L in retroperitoneal spaces. (from rupture of superior gluteal artery, iliac vessels)

Question 16

What are avulsion fractures?

Answer 16

Fracture caused by piece of bone pulled off by violent muscle contraction in athletes

Question 17

What causes pelvic ring fractures?

Answer 17

Anterioposterior compression (car)
Lateral compression (fall from height, impact from side)
Vertical sheer (falling from height onto one leg)

Question 18

What causes acetabular fractures?

Answer 18

Head of femur driven into pelvis
- Blow on side (fall from height)
- Blow on front of knee (dashboard)

*must check other injuries/fractures

Question 19

What line on Xray is disrupted in neck of femur fracture?

Answer 19

Shenton’s line

Question 20

Hip fracture nomenclatures

Answer 20

1. Intracapsular
   
   • subcapital (just under head)
   • transcervical (mid-neck)
   • basi-cervical (distal neck before
     intertrochanteric region)
2. Extracapsular
   
   • intertrochanteric
   • subtrochanteric
   • greater & lesser trochanter

Question 21

Associated symptoms of hip fracture

Answer 21

**Shortened + EXTERNALLY rotated leg

swelling & bruising - suggestive of extracapsular fracture

tenderness over femoral neck

limited ROM of hip + painful

Question 22

Complications of hip fracture

Answer 22

Neuro: cord compression, sciatic nerve compression (foot drop, loss of sensation)

Vascular: AVN, limb ischemia

Orthopedic: delayed/mal/non-union, OA, erosion of femoral head

Question 23

Which blood supply is most affected in NOF #

Answer 23

lateral epiphyseal artery - branch of medial circumflex artery

Question 24

Continue from neck of femur fractures (pg 216)