orthopedics congenital hip dislocation

1. Congenital
Hip
Dislocation
Dr. Amardeep Kaur Saini(PT)

2. CHD
• This is a spontaneous dislocation of the
hip occurring before, during or shortly
after birth.
• In western countries, it is one of the
commonest congenital disorder.
• It is uncommon in India and some
other Asian countries, probably
because of the culture of mother
carrying the child on the side of her
waist with the hips of the child
abducted This position helps in
reduction of an unstable hip, which
otherwise would have dislocated.
• The general term “dysplastic hip” is
sometimes used for these congenital
malformations of the hip.
Dr. Amardeep Kaur Saini(PT)

3. Aetiology
 Hereditary predisposition to joint laxity:
Heredity related lax joints are predisposed to hip
dislocation in some positions.
 Hormone induced joint laxity: CDH is 3-5 times
more common in females. This may be due to the
fact that the maternal relaxin (a ligament relaxing
hormone in the mother during pregnancy) crosses
the placental barrier to enter the foetus. If the
hormonal environment of the foetus is a female,
relaxin acts on the foetus's joints in the same way
as it does on those of the mother. This produces
joint laxity, and thus dislocation.
 Breech malposition: The incidence of an unstable
hip is about 10 times more in newborns with
breech presentation than those with vertex
presentation. It is possible that in breech
presentation the foetal legs are pressed inside the
uterus in such a way that if the hip ligaments are
lax, dislocation may occur.
Dr. Amardeep Kaur Saini(PT)

4. Pathology
2 Types of Dysplastic hips;
(i) those dislocated at birth (classic CDH);
(ii) those dislocatable after birth. The first are primarily
due to a hereditary faulty development of the
acetabulum, and are difficult to treat. The second are
due to underlying joint laxity, with a precipitating
factor causing the dislocation. Following changes are
seen in a dislocated joint:
 Femoral head is dislocated upwards and laterally; its
epiphysis is small and ossifies late.
 Femoral neck is excessively anteverted. Acetabulum is
shallow, with a steep sloping roof.
 Ligamentum teres is hypertrophied.
 Fibro-cartilaginous labrum of the acetabulum (limbus)
may be folded into the cavity of the acetabulum
(inverted limbus).
 Capsule of the hip joint is stretched.
 Muscles around the hip, especially the adductors,
undergo adaptive shortening
Dr. Amardeep Kaur Saini(PT)

5. Clinical Features
CDH is more common in first born babies, more on the left, more common in
females (M:F=1:5), bilateral in 20% cases. CDH may be detected at birth or
soon after; sometimes not noticed until the child starts walking.
• At birth: Routine screening of all newborns is necessary. The examining
pediatrician may notice signs suggestive of a dislocated or a dislocatable hip, as
discussed subsequently.
• Early childhood: Sometimes, the child is brought because the parents have
noticed an asymmetry of creases of the groin, limitation of movements of the
affected hip, or a click every time the hip is moved.
• Older child: CDH may become apparent once the child starts walking. Parents
notice that the child walks with a ‘peculiar gait’ though there is no pain. On
examination a CDH may be found to be the underlying cause.
Dr. Amardeep Kaur Saini(PT)

7. EXAMINATION
There may be limitation of hip abduction,
asymmetry of groin creases or an audible click.
Barlow's test: The test has two parts.
 In the first part, the surgeon faces the child's
perineum. He grasps the upper part of each
thigh, with his fingers behind on the greater
trochanter and thumb in front. The child's
knees are fully flexed and the hips flexed to a
right angle. The hip is now gently adducted. As
this is being done, gentle pressure is exerted by
the examining hand in a proximal direction
while the thumb tries to ‘push out’ the hip. As
the femoral head rolls over the posterior lip of
the acetabulum, it may, if dislocatable (but not,
if dislocated) slip out of the acetabulum. One
feels an abnormal posterior movement,
appreciated by the fingers behind the greater
trochanter. There may be a distinct ‘clunk’. If
nothing happens, the hip may be normal or may
already be dislocated; in the latter, second part
of the test would be more relevant.
Dr. Amardeep Kaur Saini(PT)

9. • In the second part of the test, with the hips in 90° flexion and
fully adducted, thighs are gently abducted. The examiner's
hand tries to pull the hips while the fingers on the greater
trochanter exert pressure in a forward direction, as if one is
trying to put back a dislocated hip. If the hip is dislocated,
either because of the first part of the test or if it was dislocated
to start with, a ‘clunk’ will be heard and felt, indicating
reduction of the dislocated hip. If nothing happens, the hip
may be normal or it is an irreducible dislocation. In the latter
case, there will be limitation of hip abduction. In a normal hip,
it is possible to abduct the hips till the knee touches the couch.

10. Ortolani's test: This test is similar to the
second part of Barlow's test. The hips and
knees are held in a flexed position and
gradually abducted. A ‘click of entrance’
will be felt as the femoral head slips into
the acetabulum from the position of
dislocation. In an older child, the
following findings may be present:
 Limitation of abduction of the hip.
 Asymmetrical thigh folds. Higher
buttock fold on the affected side.
 Galeazzi's sign: The level of the knees
are compared in a child lying with hip
flexed to 70°and knees flexed. There is
a lowering of the knee on the affected
side.
 Ortolani's test may be positive.
Dr. Amardeep Kaur Saini(PT)

12. • Trendelenburg's test is positive: This test is performed in
an older child. The child is asked to stand on the affected
side. The opposite ASIS (that of the normal side) dips down.
• The limb is short and slightly externally rotated. There is
lordosis of the lumbar spine.
• Telescopy positive: In a case of a dislocated hip, it will be
possible to produce an up and down piston-like movement
at the hip. This can be appreciated by feeling the movement
of the greater trochanter under the fingers
• A child with unilateral dislocation exhibits a typical gait in
which the body lurches to the affected side as the child
bears weight on it (Trendelenburg's gait). In a child with
bilateral dislocation, there is alternate lurching on both
sides (waddling gait).
• Some hip pathologies mimicking CDH are: Coxa vara,
posterior hip dislocation and paralytic hip dislocation and
paralytic hip dislocation.
Dr. Amardeep Kaur Saini(PT)

13. Radiological Features
In a child below the age of 1 year, since
the epiphysis of the femoral head is not
ossified, it is difficult to diagnose a
dislocated hip on plain X-rays . Von
Rosen's view may help. Ultrasound
examination is useful in early diagnosis
at birth.
In an older child, the following are the
important X-ray findings:
Delayed appearance* of the ossification
centre of the head of the femur.
Retarded development of the
ossification centre of the head of the
femur.
• Sloping acetabulum.
• Lateral and upward displacement of
the ossification centre of the femoral
head.
Dr. Amardeep Kaur Saini(PT)

14. A break in Shenton's line
Dr. Amardeep Kaur Saini(PT)

15. TREATMENT
Principles of treatment: Aim is to achieve reduction of
the head into the acetabulum, and maintain it until the
hip becomes clinically stable and a 'round' acetabulum
covers the head. In most cases, it is possible to reduce the
hip by closed means; in some an open reduction is
required. Once the head is inside the acetabulum, in
younger children, under the mould-like effect of the
head, it develops into a round acetabulum. If reduction
has been delayed for more than 2 years, acetabular
remodelling may not occur even after the head is reduced
for a long time. Hence, in such cases, surgical
reconstruction of the acetabulum may be required.
Dr. Amardeep Kaur Saini(PT)

16. Methods of reduction:
a) Closed manipulation: It is sometimes possible in younger
children to reduce the hip by gentle closed manipulation under
general anesthesia.
b) In unilateral cases, reduction can be attempted till 10 years of
age and till 8 years in bilateral cases
c) Traction followed by closed manipulation: In cases where the
manipulative reduction requires a great deal of force or if it fails,
the hip is kept in traction for some time, and is progressively
abducted. As this is done, it may be possible to reduce the
femoral head easily under general anesthesia. An adductor
tenotomy is often necessary in some cases to allow the hip to be
fully abducted.
d) Open reduction: This is indicated if closed reduction fails.
Reasons of failure of closed reduction could be the presence of
fibro-fatty tissue in the acetabulum or a fold of capsule and
acetabular labrum (inverted limbus) between the femoral head
and the superior part of the acetabulum. In such situations, the
hip is exposed, the soft tissues obstructing the head excised or
released, and the head repositioned in the acetabulum.
Dr. Amardeep Kaur Saini(PT)

17. Maintenance of reduction:
Once the hip has been
reduced by closed or open
methods, following
methods may be used for
maintaining the head
inside the acetabulum.
a) Plaster cast: A frog leg or
Bachelor's cast.
b) Splint: Some form of
splint such as Von Rosen's
splint. External splints can
be removed once the
acetabulum develops to a
round shape. The hip is
now mobilized, and kept
under observation for a
period of 2-3 years for any
recurrence. Dr. Amardeep Kaur Saini(PT)

18. Acetabular reconstruction procedures:
a) Salter's osteotomy: This is an osteotomy of the iliac bone,
above the acetabulum. The roof of the acetabulum is rotated with
the fulcrum at the pubic symphysis, so that the acetabulum
becomes more horizontal, and thus covers the head.
b) Chiari's pelvic displacement osteotomy: The iliac bone is
divided almost transversely immediately above the acetabulum,
and the lower fragment (bearing the acetabulum) is displaced
medially. The margin of the upper fragment provides additional
depth to the acetabulum.
c) Pemberton's pericapsular osteotomy: A curved osteotomy as
shown in this is made. The roof of the acetabulum is deflected
downwards over the femoral head, with the fulcrum at the
triradiate cartilage of the acetabulum.
In some cases, reduction of the hip may be possible only in
extreme abduction or internal rotation of the thigh. In such cases a
varus derotation osteotomy is done at the sub-trochanteric region.
The distal fragment is realigned and the osteotomy fixed with a
plate. Dr. Amardeep Kaur Saini(PT)

19. Dr. Amardeep Kaur Saini(PT)

20. Treatment Plan
Treatment varies according to the age at which the patient presents.
this has been divided into four groups on the basis of age of the
patient:
• Birth to 6 months: The femoral head is reduced into the
acetabulum by closed manipulation, and maintained with plaster
cast or splint.
• 6 months to 6 years: It may be possible up to 2 years to reduce
the head into the acetabulum by closed methods. After 2 years, it is
difficult and also unwise to attempt closed reduction. This is
because, when the head has been out for some time, the soft tissues
around the hip become tight. Such a hip, if reduced forcibly into the
acetabulum, develops avascular necrosis of the femoral head. In
these cases, reduction is achieved by open methods, and an
additional femoral shortening may be required. In older children, an
acetabular reconstruction may be performed at the same time or
later. Salter's osteotomy is preferred by most surgeons.
Dr. Amardeep Kaur Saini(PT)

21. • 6-10 years: The first point to be decided in children at this age is
whether or not to treat the dislocation at all. No treatment may be
indicated for children with bilateral dislocations because of the
following reasons:
• The limp is less noticeable.
• Although having some posture and gait abnormalities, these patients
tend to live normal lives until their 40's or 50's.
• Results of treatment are unpredictable and a series of operations may
be required.
• In unilateral cases, an attempt at open reduction with reconstruction
of the acetabulum may be made. A derotation osteotomy is needed in
most cases.
• 11 years onwards: Indication for treatment in these patients is pain. If
only one hip is affected, a total hip replacement may be practical once
adulthood is reached. Sometimes, arthrodesis of the hip may be a
reasonable choice.
Dr. Amardeep Kaur Saini(PT)

23. Dr. Amardeep Kaur Saini(PT)