DEVELOPMENTAL DYSPLASIA OF THE HIP

Question 1

DDH

Answer 1

abnormal development of the hip resulting in dysplasia and possible displacement/subluxation of the coxofemoral joint due to capsular laxity and some mechanical issues.

Question 2

Development abnormality

Answer 2

bony structures 
(proximal femur and acetabulum), 
labrum,
joint capsule and 
soft tissue

Question 3

Crucial – an early diagnosis

Answer 3

Ultrasonography
Screening
Minimal treatment techniques to lower morbidity and fast recovery

Question 4

ANATOMY

Answer 4

Normal development of the hip – depends on :

1. Normal growth of the triradiate cartilage
2. Bone ossification nuclei of the acetabulum (ilion, ischion and pubis)
3. A spherical femoral head and congruency with the acetabulum (centered)

Question 5

At birth– cartilaginous structures:

Answer 5

acetabulum
entire femoral head
femoral neck - partially
greater trochanter

Question 6

FISIOPATHOLOGY

Answer 6

Presure ↑↑ on the cartilaginous FH ► ↓ blood perfusion► necrosis of the chondrocytes
Affects FH and growth cartilage
Doesn’t affect the greater trochanter (normal dimensions)

Muscular imbalance :
Deteriorates growth and morphology of the proximal femur
Contracture of the adductors
Improper function (weakening) of the abductors

Question 7

ETIOLOGY

Answer 7

Multifactorial

1. Laxity of the ligaments and capsules
2. Race – caucasians – a smaller acetabulum
3. In utero position (20%)
4. Oligohydramnios
5. Sex (80% - females)

Genetic susceptibility
History - x 10 incidence in children with DDH parents
- twins - 34% (monozygotic)

Question 8

EPIDEMIOLOGY

Answer 8

Incidence
Most frequent pediatric orthopedic issue in newborns
dysplasia - 1:60-100
luxation (displacement) - 1:1000

Barlow – instabilitaty 1 out of 60 nb.
60% get stable during the first week and stabile 80% up to the age of 2 months (0,2% remain with residual hip dysplasia)

Question 9

EPIDEMIOLOGY

localization and demographics

Answer 9

Localization

• Most frequent in the left hip of girls
• Bilateral in 20%

Demographics
Frequent in Native Indians, Laplanders, Balcans (Romania – unknown incidence)
Rare in africans

Question 10

PROGNOSIS OF DDH

Answer 10

Diagnosed early and properly – very good prognosis

Treatament by closed reduction - prognostic bun
Failure of conservative treatment – open reduction – uncertain prognosis, at least good for a short term

According to R. Graf - DDH diagnosis during the first 14 days of life and a proper treatment (ultrasound) – healing up to 3 months of life

Question 11

Ortolani (Le Damany,1912) sign

Out of 3 cases only one develops DDH

Answer 11

Hip abduction (45-60°), pushing the greater trochanter→ FH centers

Question 12

Barlow’s sign

Answer 12

Adduction and pressure on the knee and inner thigh→ FH exits the acetabulum

Question 13

CLINICAL EXAM

other signs

Answer 13

1. Galeazzi
2. Limited abduction
3. Piston sign
4. Lumbar Hyperlordosis
5. Gluteal/inguinal fold assimetry
6. Trendelenburg sign and walking (insufficiency of the pelvitrochanteric muscles)

Question 14

IMAGISTICS

Answer 14

Hip ultrasound–Graf (most used), Harcke

Recommended – SCREENING (and clinical exam)

Question 15

CLASSIFICATION AFTER GRAF
CENTERED HIP TYPE I
NORMAL

Answer 15

Type I: • α angle ≥ 60º, β < 77º
• stable hip
(Ortolani and Barlow negative)

High risk hip -> surveillance

Type I: • α ≥60º
• familial history positive

Question 16

CENTERED HIP TYPE II – ß < 77º

Answer 16

Type II a : • acetabular dysplasia (0 – 3 months)
• α = 50º - 59º
medical surveillance

Type II b : • acetabular dysplasia (3 – 12 months)
• α = 50º - 59º
Pavlik harness

Type II c : • acetabular dysplasia (0 – 12 months)
• α = 43º - 49º
palster casting in human position

Question 17

DECENTERED HIPS TYPE D, III & IV

Answer 17

Type D • α = 43º - 49º
• ß > 77º
• eversed labrum

    Type III a and b  • α < 43º

    Type IV   • α < 43º
		   • inversed labrum

adductor tenotomy

open reduction Ludloff /Smith-Petersen and
plaster casting

Question 18

Other imagistic exams

Answer 18

1. Xrays
2. Artrography
3. MRI
4. CT/CT-3D – not useful

Question 19

NATURAL EVOLUTION OF DDH

Answer 19

Untreated cases of DDH may
↓
Instability
↓
Degenerative changes 
present in teenagers
↓
Severe degenerative changes
↓
Osteoarthritis
(early hip surgery)

Question 20

TREATAMENT OF DDH

Answer 20

Conservative (according to R. Graf)
Phase
1.Reduction -Decentered hips(D,III,IV) - Manually,by extension,Pavlik
2.Retention - Unstable hips ( IIc unstable) - Human position,plaster according to f..
3.Maturation - Stable ‘‘dysplastic’’ hips ( IIc stable,IIb,IIa-) - Harness according M.Graf/Pavlik

Question 21

Frejka pillow

Answer 21

a pillow splint used for abduction and flexion of the femurs in treatment of congenital hip dysplasia or dislocation in infants.

Question 22

Pavlik harness

Answer 22

a support device used to immobilize a body part or hold it in position.
Pavlik harness a device used correct hip dislocations in infants with developmental dysplasia of the hip, consisting of a set of straps that hold the hips in flexion and abduction.

Question 23

Surgery

Answer 23

1. Adductor release (tenotomy)
2. Open reduction
3. Derotation osteotomies
4. Acetabuloplasties
5. Arthroplasties

Question 24

Open reduction and pelvic osteotomies

Answer 24

Salter, Pemberton, Dega, Hopf, Steel, Ganz, Chiari, Dial, Shelf, etc.)

Question 25

CONCLUSIONS

Answer 25

Early diagnosis, early treatment

US Screening + clinics
Healing up to 3 months of age

Untreated – LLD (limb length discrepancies), limping, hip pain and early osteoarthritis

Even if treated properly hip arthritis is not excluded (especially for late treatment)