Congenital hip dysplasia – causes, symptoms, diagnosis, treatment, pathology


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much more. Try it free today! Congenital hip dysplasia, or developmental
dysplasia of the hip, is a problem where the socket or acetabulum – and the femoral head
are misaligned, resulting in an unstable hip joint. Typically, the problem is present at birth,
but sometimes it appears later as the bones develop over time. The hip joint is a ball and socket type because
the ball-shaped head of the femur sits and rotates within the acetabulum which is a cup-shaped
socket. The hip joint is supported by a tough fibrous
joint capsule, which is made up of three main ligaments, the iliofemoral, the pubofemoral,
and the ischiofemoral. The main job of the joint capsule is to hold
articulating bones together and make sure the joint stays stable when the hip is moving. Now, the acetabulum itself is a combination
of parts of three pelvic bones that join together – the ischium, the ileum, and the pubis. At the bottom of the acetabulum known as the
acetabular fossa, arises a ligament, called the ligamentum teres that attaches to the
fovea capitis, which is a depression found on the tip of the femoral head. This ligament helps with joint stability especially
during hip flexion and abduction. Now, the edge of the acetabulum has a thick
bony circular rim covered by a ring of cartilage known as the acetabular labrum. At its lower end, there’s a depression called
the acetabular notch, which is covered by the transverse ligament which fills the gap
within the circumference of the acetabulum. Now, the normal development of a hip joint
requires that the femoral head stays fitted within the acetabulum so that they both grow
together keeping their sizes and shapes proportional. In congenital hip dysplasia, the femoral head
dislocates out of its acetabulum during development, and as a result, the ball and the socket grow
out of proportion to one another, so that they’re unable to form a normal stable joint. The cause of the dislocation isn’t always
known. But one situation that can give rise to the
problem is when too much mechanical force is applied against a fetal thigh, it can cause
the femoral head to slip out of the acetabulum. This can happen when a baby is lying in a
breech position within the mother’s uterus, resulting in the baby’s buttocks being near
the cervix at the time of delivery. This sort of mechanical force is most likely
to occur with firstborns, because the mother’s uterus is not as stretched out, putting a
lot of pressure on a baby’s thighs. This can also happen when there is not enough
amniotic fluid to expand the uterine cavity so that the fetus can have enough room for
its legs. When the femoral head spends a lot of time
outside of the acetabulum, the acetabular structures specifically the labrum, ligamentum
teres, and the transverse ligament start hypertrophying within the acetabular fossa and occupy the
space for the femoral head. In other words, the socket becomes “more
shallow”, making for a poor fit for the femoral head. Symptoms of congenital hip dysplasia may differ
according to the age. Some newborns and infants may present no symptoms,
but may have legs of unequal length or asymmetric skin folds around the groin. Older kids may present with painless limping
and a waddling gait, and when this doesn’t get properly treated, it may develop into
a painful osteoarthritis in adulthood. The diagnosis of congenital hip dysplasia
is based on physical exam. There are several techniques for examining
the hip such as the Barlow maneuver, which consists of adducting the hip while holding
the knee straight, and when this pops the femoral head out of the socket, this raises
suspicion of hip dysplasia. To confirm the dislocation, the Ortolani maneuver
is done and this consist of flexing the baby’s hip at 90°, and then gently abducting it. If the femoral head was out of the socket,
Ortolani maneuver will cause it to slip back into the acetabulum, which will feel and sound
like a clunk. Also, imaging like ultrasound and X-rays can
be used to assess the position of the femoral head and the structure of the acetabulum. Now, the treatment of congenital hip dysplasia
depends on age and extent of the deformity. Below six months, the deformity is usually
corrected by holding the hip joints with an abduction splint such as a harness, specifically
Pavlik harness that holds the hip joint flexed and abducted for a period of one to two months. This help to keep the femoral head within
the socket to promote normal hip joint development. If the baby is older than six months, reduction
under anesthesia may be needed to manually reduce the femoral head back into the acetabulum. If closed reduction doesn’t work, surgery
might be necessary for open reduction, which is followed by a special hip cast that immobilizes
the femoral head inside the acetabulum as it’s healing. Alright, as a quick recap, … in congenital
hip dysplasia, the femoral head and the acetabulum don’t develop proportionally to one another,
which causes them to misalign, forming an unstable hip joint. Children with congenital hip dysplasia present
with legs of unequal lengths and asymmetric skin folds around the groin, and they may
develop limping and waddling gait when they start walking. Below six months, congenital hip dysplasia
is treated with a Pavlik harness, and close or open reduction for older kids, and in some
cases surgery might be necessary.

16 comments

  1. I was born with this kindly give me suggestion regarding this except surgery m working employee I have problem on both side sometimes it give me a pain but there is no problem when I was doing heavy work but after that there is a mild pain m 32 at present m waiting for reply

  2. I was trying to read CHD from my book with no luck and this notification shows up… Yayyy😀 I love you osmosis

  3. 4:40 Correction
    Confirmed via ultrasound (x-ray not used until ~4-6 months because cartilage is not ossified).

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