Hip OA

Question 1

Forces through the hip
1) standing
2) walking level normal
3) walking up stairs
4) running

Answer 1

1) 0.5 body weight
2) 2.4 x body weight
3) 2.5 body weight
4) 3-4 x body weight

Question 2

Primary OA Risk factors

Answer 2

• wear and tear
• obesity: for every added lbs of BW an additional 3 lbs may act at the hip
• age: mid age to elderly
• overuse and abuse: sports/occupation

Question 3

Secondary OA: risk factors/what is it

Answer 3

• follows a traumatic injury
• Disease
• Anatomic alignment
• capsular tightness/hypomobility

Question 4

what traumatic injuries can cause secondary OA

Answer 4

• hip dislocation
• hip fracture
  (femoral head, femoral neck, intertrochanteric, subtrochanteric/shaft)

Question 5

What conditions can lead to DJD of the hip

Answer 5

• congenital hip dysplasia/dislocation
• Legg Perthes: osteochondrosis - 3-10 y/o
• slipped capital femoral epiphysis 10-16 y/o

Question 6

Anatomic alignment issues that can cause OA

Answer 6

• abnormal forces at the hip
• excessive anteversion, retroversion
• leg length asymmetry = longer leg has an increase forces on superior lateral acetabulum and femoral head
• femoral-acetabular impingement

Question 7

Hip angle of inclination

Answer 7

• forces are not ideally located on the hip when there is an abnormal angle
• coxa vara = <125
• coxa valga = >125

Question 8

Anteversion/retroversion

Answer 8

• neck torsion angle
• normal = 15 anterversion
• excessive anteversion = >15
• retroversion <15

Question 9

Femoral acetabular impingement

Answer 9

• CAM impingement: large FH and small acetabulum
• Pincer type impingement: larger overhanging acetabulum
• combination of pincer and CAM
• these may result in degeneration of the hip joint labrum and articular cartilage

Question 10

How can a tight capsule of the hip or hypomobilty cause secondary OA

Answer 10

• increase compressive forces in a smaller contact area
• “shock loading” = compression in a small contact area coupled with the high compressive forces of WB
• decreased movement of synovial fluid/distribution of nutrients
• leads to less nutrients to articular cartilage

Question 11

Effect of a hip flexor contracture on standing

Answer 11

BW is more anterior
- more joint reaction forces due to glute max needing to contract
- increase in forces to hip joint in area of thinner articular cartilage

Question 12

How does articular degeneration occur?

Answer 12

1. decrease in GAGs, proteoglycans and H2O biding capacity
2. chondrocytes turn off = dont keep up with attrition of cells
3. cartilage collagen fibers thinner, stiffer, less elastic
4. decreased ability to deform, absorb shock, decrease force attenuation
5. increase forces to subchondral bone causing sclerosis

Question 13

what else can happen with OA in addition to degradation of articular cartilage

Answer 13

• osteophytes at joint margins leading to irritation of synovial capsule
• inflammation/synovitis/thickened synovium leads to capsular fibrosis which decreases ROM and nutrition
• cycle of progression

Question 14

Hip OA diagnosis

Answer 14

• DX: X-ray in standing
• decreased joint space = loss of articular cartilage
• sclerosis on the subchondral bone (related to the increase in forces)
• pseudocytes: synovial fluid pushed into bony porous areas
• osteophytes at joint margins

Question 15

Hip OA signs in the history and interview

Answer 15

Complaints of:

• pain in groin, anterior thigh, lateral thigh, posterior thigh
• pain worsens with WB or increase hip stresses

Signs:

• decrease ROM = difficulty with donning socks and shoes, squatting, stairs
• gradual onset/post trauma
• morning stiffness (1/2 hr), better mid-day with movement
• increased pain end day due to excessive activity and WB

Hx:

• childhood hip pathology

Question 16

What makes OA pain better /worse

Answer 16

• mild activity
• stiff with prolonged static postures
• worse with prolonged WB

Question 17

what are some symptoms of advanced DJD

Answer 17

• constant ache
• resting pain
• night pain

Question 18

Hip OA DJD signs and symptoms

Answer 18

• patient c/o stiffness and swelling
• decreased ROM
• pain stiffness - unilateral
• muscule atrophy, weakness
• arthrogenic inhibiton (hip abductors, ERs, extensors)

Question 19

What are some observations/inspections that are noted with OA patients

Answer 19

• (+) trendelenberg
• contralateral pelvic drop
• hip flexor contracture
• hip alignment: anteversion/retroversion, Toe in/out, femoral torsions (structural)
• knee valgus/varus
• foot pronation/supination
• leg length descrepancy
• gait deviations/compensations

Question 20

AROM/PROM findings with OA patients

Answer 20

• end feel: abnormal capsular stiff without creep

capsular pattern:
- marked limitation IR, abduction
- moderate limitation: felxion and extension
- less limtation: ER

Question 21

Joint mobility test/joint play for OA

Answer 21

• loose pack position: 30 flexion, abduction and slight ER
• assess hip mobility:
  1. long axis distraction
  2. hip lateral distraction
  3. hip assess end feel OP: IR/ER, add/abd, flex/ext
• arthrokinematic glides: convex on concave

Question 22

Muscle testing for hip OA patients

Answer 22

• common to see weak abductors, extensors, ER

Question 23

Muscle length tests that can be done with hip OA patients

Answer 23

• Hams: SLR, 90/90
• iliopsoas: thomas
• rectus femors: mod thomas/Ely’s test
• ITB/TFL: obers, modified obers
• piriformis: FAIR
• sign of buttock: (+) hip ROM is the same when knee is flexed

Question 24

Special tests for OA patients

Answer 24

• trendelenburg test: stand on involved leg, pelvis drops opposite, weak abductors isplaterally
• leg length: screen as in lab or measure
• craig test: prain anteversion = 15 anteversion angle is normal
• compression:
• distraction long axis
• FABERS
• Scour test
• log roll

Question 25

Clinical prediction rule for Hip OA

Answer 25

- limited passive IR (25 or less) - limited active hip flexion with lateral hip pain - active hip extension causes pain - squatting limited and painful - scour test w/ adduction - lateral hip groin pain

Question 26

hip OA treatment

Answer 26

- weight reduction - exercise (low impact) - activity modification/joint protection (shock absorbing shoes/insoles, work matts) - medications - supplements: glucosamine chondroitin sulfate, tumeric, omega 3 fatty acids, fish oil, flax seeds (studies show is may provide lubircation but not grow AC) - Promote ROM - alternate activites and rest period - strengthen (low intensity) - balance activites

Question 27

History/risk factors for hip OA

Answer 27

- advanced age - previous hip developmental disorder - legg calve perthes - slipped capital femoral epiphysis - hip dysplasia - previous hip injury

Question 28

OA dx classification **experts opinion = consider a differential dx if not common presentation as in**

Answer 28

- moderate anterior groin/lateral pain - >50 years old - morning stifnfess < 1 hr - Hip IR, flexion limited >15 to uninvolved

Question 29

Validated outcome measures for Hip OA

Answer 29

- WOMAC western Ontario and McMaster University - LEFs - Harris Hip score

Question 30

What additional tests can be used to assess the patients function for Hip OA

Answer 30

- 6 minute walk test - covers 6 meters - TUG: timed 3 meters returned to chair - self paced walk - timed walk 4-40 meters - stair measure - timed going up and down 9 stairs **hip OA patients demonstrate lower performance on functional testing**

Question 31

What should be included with patient education for hip OA patients

Answer 31

- activity modification - unloading joints - weight reduction - exercise

Question 32

Low impact exercise for hip OA

Answer 32

- ROM/flexibility - strength = stronger muscles will absorb more force - endurance

Question 33

Manual therapy for hip OA

Answer 33

- mobs to improve mobiltiy - provide short term pain relief