Hip

Question 1

Where do hip dislocations occur

Answer 1

MC: posterior

10% anterior

Question 2

What causes hip dislocations

Answer 2

Trauma at the axis of femur- Axial load with flexed knee, or MVA

Question 3

Etiology of a posterior hip dislocation is

Answer 3

Hip and knee flexed 90 degrees and there is force exerted at knee through femoral shaft
Causes femur head to be driven posteriorly= Posterior displacement of femoral head from acetabulum

Question 4

How can you tell someone has a posterior hip dislocation

Answer 4

Lower extremities in scissor position (hip internally rotated, adducted, flexed, with knee flexed
Shortened extremity
Greater trochanter and femoral head prominent under gluteal muscles

Question 5

Etiology an an anterior hip dislocation

Answer 5

Abduction and external rotation of femur causing anterior displacement of femoral head from acetabulum

Question 6

How can you tell someone has an anterior dislocation

Answer 6

LE in “helpless eversion”, hip externally rotated and abducted
flattened lateral hip
prominence of femoral head in groin

Question 7

Complications of hip dislocations include

Answer 7

Acetabular fracture
Sciatic nerve injury
Rupture of ligamentum teres artery causing avascular necrosis of femoral head

Question 8

How do you perform a posterior hip reduction

Answer 8

Two providers. Patient lies in fetal position with affected leg on top
P1: Stand in front of affected knee, wrap band around pt’s posterior knee and his torso
P2: Stand at pt’s rear, wrap band around pit’s hip and his torso
Two providers pull opposite each other until it pops back in

Question 9

MOI of hip fractures are

Answer 9

Fall: elderly w/ osteoporosis
Stress: long distance runner
Pathologic: mets and primary bone lesions

Question 10

How do hip fractures present clinically

Answer 10

Pain radiating to groin and inner thigh
Difficulty w/ flexion and IR (so hold legs in ER and abducted)
Leg may appear shorter

Question 11

What imaging do you get for suspected hip Fx

Answer 11

1st line: X-Ray

CT for detailed evaluation

Question 12

What are the types of hip fractures

Answer 12

Subcapital
Intertrochanteric
Subtrochanteric

Question 13

How do you treat hip fractures

Answer 13

ORIF vs arthroplasty (artificial hip)

Question 14

What is avascular necrosis of the hip

Answer 14

Los of blood supply leading to destruction of femoral head

Question 15

Explain avascular necrosis of hip in adults

Answer 15

30-50 y/o
Uni or B/l
RF: Hx trauma, long term steroid use, EtOH abuse, radiation therapy, RA, SLE

Question 16

What is Legg Calve Perthes disease

Answer 16

2-11 y/o
M>F
Unilateral, idiopathic avascular necrosis of the hip

Question 17

How does avascular necrosis present

Answer 17

Insidious onset, loss of ROM to IR and abduction

adult: groin pain is initial complaint- pain with weight bearing/limp
kid: painless limp is initial complaint- groin, thigh or knee pain may follow

Question 18

What are the Ficat stages of avascular necrosis

Answer 18

I- normal
II- sclerotic or cystic lesions, no subchondral prolapse
III- subchondral collapse (crescent sign)
IV- OA w/ decreased articular cartilage and osteophytes

Question 19

What is the earliest imaging finding in avascular necrosis

Answer 19

Crescent sign; a dark sliver along the medial superior portion of the femoral head
-if it’s a peds XR, always pay attention to open growth plates; dont mistake for pathologic finding

Question 20

What is thlack mortinson sign

Answer 20

When you can see the male genitalia pointing to the side of the pathology on XR
this is a joke… lol..

Question 21

What is imaging of choice for early detection of avascular necrosis

Answer 21

MRI!

Question 22

How do you treat avascular necrosis in adults

Answer 22

Core decompression w/ bone graft

total hip replacement if advanced disease, or graft fails

Question 23

How do you treat avascular necrosis in children

Answer 23

Bed rest followed by progressive weight bearing

Question 24

What is femoroacetabular impingement

Answer 24

hip impingement between femoral head and neck bump straight (cam lesion), and acetabular over coverage (pincer lesion)
-Can have Cam and Pincer separate or simultaneously

Question 25

Femoroacetabular impingement can lead to

Answer 25

hip labral tears
chondral injury
early onset OA

Question 26

What causes femoroacetabular impingement

Answer 26

Development of hip and acetabulum during childhood is off
Not felt to develop more over time
*Athletes and active individuals at risk for earlier development 2/2 high demands to hip

Question 27

How does femoroacetabular impingement present

Answer 27

Pain localized to groin- dull ache at rest and post activity, sharp stabbing pain w/ turning, twisting, and squatting
Clicking, catching, and rarely, locking

Question 28

What is the impingement test

Answer 28

Flexion, Adduction and IR of hip causes severe anterior pain
very sensitive, not very specific

Question 29

What imaging should you get for suspected femoroacetabular impingement

Answer 29

Plain radiograph
MRI (better sensitivity with arthrogram so you can see labral tears)
Marcaine (kenalog) injection test

Question 30

Non-surgical FA impingement treatment is

Answer 30

Activity modification
NSAIDs
PT for hip capsular stretching, ROM and strength exercise

Question 31

Surgical Tx for FA impingement includes

Answer 31

address isolated pincer, cam, or combined pincer and cam lesion

Question 32

What is hip OA

Answer 32

degeneration of cartilage from femoral head/acetabulum

can be primary idiopathic, trauma, infection, SCFE, legg-calve-perthe disease, DDH, or avascular necrosis

Question 33

Clinical features of OA of hip are

Answer 33

groin/anterior thigh pain w/ weight bearing or at rest
decreased and painful ROM (flexion and IR)
Difficult to cross legs or put shoes/socks on
+/- referred pain to the knee

Question 34

How do you treat hip OA

Answer 34

APAP, NSAIDs, narcotics 
weight reduction 
lifestyle modification 
intraarticular steroid injection/viscosuplementation 
joint arthroplasty

Question 35

What is trochanteric bursitis

Answer 35

inflammation and hypertrophy of greater trochanteric bursa
*pain and tenderness over greater trochanter
distal pain radiation
pain worse when you first rise from seated position, but feels better after a few steps. but recurs after walking for 30+ min
*Night pain, cant lie on affected side

Question 36

How do you treat trochanteric bursitis

Answer 36

Radiograph o r/o bony abn
NSAIDs and activity modification to reduce inflammation and pain
Stretching IT band and gluteal musculature
US guided injection of local anesthetic and steroid into greater trochanteric bursa