Kids with a leg length discrepancy have legs that are different lengths. This happens
because the thigh bone (femur), shinbones (tibia or fibula), or both are shorter in
one leg.
What Are the Signs and Symptoms of Leg Length Discrepancy?
Signs and symptoms of a leg length discrepancy depend on the cause and how much
shorter one leg is. A small difference in leg length might not be noticeable at all.
A bigger difference can cause a limp or pain. It can also lead to arthritis as an
adult.
Depending on how old a child is and the cause of the discrepancy, the difference
may stay the same or get worse as the child grows.
What Causes Leg Length Discrepancy?
Leg length discrepancy can be present at birth (called congenital),
but might not be noticeable until a child gets older. It also can develop when a child
is older (called acquired).
Causes of congenital leg length discrepancy include:
fibular hemimelia
(when a baby is born with a short or missing shinbone)
focal femoral deficiency (when a baby is born with a short or missing thigh bone)
hemihypertrophy (when one side of the body grows larger than the other)
Causes of acquired leg length discrepancy include:
a broken leg bone
a bone infection
An idiopathic leg length discrepancy is one where the cause isn't
known.
How Is Leg Length Discrepancy Diagnosed?
To diagnose a limb length discrepancy,
specialists (doctors and other health
care providers who treat bone and muscle problems):
talk to the family and the child (if he or she is old enough)
If a child has only a slight difference in leg length, a shoe lift can even things
out. This may be all some kids need. But if the difference in leg length is more than
1 inch (2.5 cm) or gets worse as the child grows, surgery can help. Kids may need
more than one surgery as they grow.
An option for kids who are still growing is epiphysiodesis (pronounced:
ep-i-fiz-ee-uh-DEE-sis). In this relatively simple outpatient surgery, one or two
of the growth plates in the longer leg are scraped or compressed with surgical plate
and screws. A growth plate is an area at the end of the bone where new growth happens.
The surgery slows or stops the longer leg from growing so the shorter leg can catch
up.
If a child has stopped growing, orthopedists can sometimes correct a leg length
discrepancy by shortening the longer leg. This is done by removing a piece of bone
from the longer leg.
Limb lengthening surgery also can be done. In this surgery, the shorter limb is
lengthened through a device on the outside of the body (an external
fixator) or a device placed inside the bone (such as
the PRECICE® limb lengthening device). This surgery requires a stay in the hospital
and weeks to months of follow-up care and rehabilitation.
What Can Parents Do?
Fixing leg length discrepancy can take many years. Parents and the orthopedic care
team play a big role in treatment.
Here are things you can do:
Talk to your child's care team about treatment and healing. Ask questions. Find
out what each surgery is for and how to care for your child afterward.
Take your child to all scheduled medical appointments.
If your child is old enough, talk about treatments and what to expect. Include
older kids in surgery decisions when you can.
Looking Ahead
Your orthopedic team will help you find the best treatment for your child. Take
time to understand exactly what will happen at each stage of the treatment plan. This
way, you and your child know what to expect and can follow the plan. Always remember
that your orthopedic care team is there to answer any questions and help you get the
best result for your child.