In this section
Developmental dysplasia (or dislocation) of
the hip (DDH) is an abnormal development of the hip joint. The ball
at the top of the thighbone (called the femoral head) is
not stable within the socket (called the acetabulum). The
ligaments of the hip joint which hold it all together may also be
stretched and loose. Sometimes, the hips dislocate after birth and this may
not be noticed until your child starts to walk.
Sometimes the signs are hard to see, even by a
Pregnant women secrete hormones in their
bloodstream which allows their ligaments to relax. These hormones help the delivery of the baby through the mother's pelvis. Some of these hormones
enter the baby's blood and can make the baby's ligaments relaxed as well. This can make the hip joint loose in the socket. The way
the baby lies in the uterus can also cause the hip joint to become
loose or dislocate.
DDH is more common in girls, firstborn
children, babies born in the breech position (i.e. bottom first) and in
families where a parent has had a dislocated hip joint. DDH can be
in one or both hip joints.
It is important to check for and treat DDH as
early as possible.
Babies with DDH can be successfully treated
with a special splint. The splint holds the hip joint in the
correct position so that the ligaments tighten. Your child may
need to wear the splint for several months, until the hip is
stable or X-rays are normal. One commonly used splint is called a
If splinting does not work, your child may
need a procedure called a 'closed reduction'. The hip joint is
moved into the correct position while your child is asleep under
anaesthetic. Children then need to wear a 'hip spica'
plaster cast to keep the hip in the right position.
Sometimes, when the above treatments do not
work or DDH is diagnosed late, your child may need what is called
an 'open reduction'. The hip joint is moved into the correct
position while your child is asleep under anaesthetic. The hip
joint is made more stable by surgery to the surrounding
tendons. This is done through a small cut in the
groin. Children then need to wear a 'hip spica' to
keep the hip in the right position.
A hip spica is a plaster cast that
covers your child's body from the knees to the waist. Hip spicas may
need to be worn for a number of months. Children may then need
to wear different splints or braces to make sure the hip joint
remains stable and in the right position.
See the Kids Health Info fact sheet: Hip Spicas
Occasionally, when DDH is diagnosed late, more surgery to the thigh or pelvic
bones may need to be done to make sure the hip joint stays in
place. This surgery is called 'osteotomy'.
Splints and bracing, such as Pavlik Harness,
can be done as an outpatient at the RCH. It is done through
the Orthotics Department.
Children needing closed reduction or open
reduction need an anaesthetic and will be admitted to
hospital. How long they stay in hospital depends on what
treatment they are having. Usually it is between one day
(called 'day stay') and three days.
While in hospital, your child will have the
following treatment and care:
If DDH is not treated, your
child may develop a painless limp when walking, they may walk on their toes rather than in a heel-and-toe action, or they may develop a 'waddling' walk. In time, arthritis will develop in the untreated hip joint
which will become painful.
Developed by the RCH Orthopaedic Unit.
First published: July 2006. Updated November 2010.