The thighbone (femur) is the largest and strongest bone in the body. It can break
when a child experiences a sudden forceful impact.
The most common cause of thighbone fractures in infants under 1 year old is child
abuse, which accounts for approximately 70% of the fractures. Child abuse is also
a leading cause of thighbone fracture in children between the ages of 1 and 4 years,
but the incidence is much less in this age group.
In adolescents, motor vehicle accidents (either in cars, bicycles, or as a pedestrian)
are responsible for the vast majority (up to 90%) of femoral shaft fractures.
Events with the highest risk for pediatric femur fractures include:
Femur fractures vary greatly. The pieces of bone may be aligned correctly (straight)
or out of alignment (displaced), and the fracture may be closed (skin intact) or
open (bone piercing through the skin). An open fracture is rare.
Specifically, thighbone fractures are classified depending on:
A thighbone fracture is a serious injury. It may be obvious that the thighbone is
Take your child to the emergency room right away if you think he or she has a broken
thighbone. Explain exactly how the injury occurred. Tell the doctor if your child
had any disease or other trauma before it happened.
The doctor will give your child pain relief medication and carefully examine the
leg, including the hip and knee. A child with a thighbone fracture should always
be evaluated for other serious injuries.
Your orthopaedic doctor will need x-rays to see what the broken bone looks like
(refer to "Classification"). Your child's healthy leg may also be x-rayed for comparison.
The orthopaedic doctor will also check the x-ray for any damage to the growth area
(growth plate) near the end of the femur. This is the part that enables the child's
bone to grow. If needed, surgery may help to restore the growth plate's function,
and regular x-rays may be taken for many months to track the bone's growth.
To treat a child's thighbone fracture, the pieces of bone are realigned and held
in place for healing. Treatment depends on many factors, such as your child's age
and weight, the type of fracture, how the injury happened, and whether the broken
bone pierced the skin.
In some thighbone fractures, the doctor may be able to manipulate the broken bones
back into place without an operation (closed reduction). In a baby under 6 months
old, a brace (called a Pavlik Harness) may be able to hold the broken bone still
enough for successful healing.
Spica casting. In children between 7 months and 5 years old, a
spica cast is often applied to keep the fractured pieces in correct position until
the bone is healed.
There are different types of spica casts, but, in general, a spica cast begins at
the chest and extends all the way down the fractured leg. The cast may also extend
down the uninjured leg, or stop at the knee or hip. Your doctor will decide which
type of spica cast is most effective for treating your child's fracture.
Your doctor will sedate your child for the closed reduction, and apply a spica cast
immediately (or within 24 hours of hospitalization) to keep the fractured pieces
in correct position until healing occurs.
When a bone breaks and is displaced, the pieces often overlap and shorten the normal
length of the bone. Because children's bones grow quickly, your doctor may not need
to manipulate the pieces back into perfect alignment. While in the cast, the bones
will grow and heal back into a more normal shape.
In general, for the best results, the broken pieces should not overlap more than
2 cm when in the cast. The growth of the thighbone may be temporarily increased
by the trauma. The mild shortening from the overlap will resolve.
Traction. If the shortening of the bones is too much (more than
3 cm) or if the bone is too crooked in the cast, it may be helpful to put the leg
in a weight and counterweight system (traction) to make sure the bones are properly
Doctors generally agree that displaced femur fractures that have shortened more
than 3 cm are not acceptable and require treatment to correct at least a portion
of the shortening.
In some more complicated injuries, the doctor may need to surgically realign the
bone and use an implant to stabilize the fracture.
Doctors are treating pediatric thighbone fractures more often with surgery than
in previous years due to the benefits that have been recognized. These include earlier
mobilization, faster rehabilitation, and shorter time spent in the hospital.
In children between 6 and 10 years old, flexible intramedullary (inside the bone)
nails are often used to stabilize the fracture. Over the past decade, this treatment
method has gained great acceptance.
Occasionally, the broken bone has too many pieces and can not be treated successfully
with flexible nails. Other options that can lead to successful outcomes in this
As the child nears the teenage years (11 years to skeletal maturity), the most common
treatment choices include either flexible intramedullary nails or a rigid locked
intramedullary nail. The rigid nail is particularly useful when the fracture is
unstable. Both types of nails allow for the child to begin walking immediately.
Generally, children who sustain a thighbone fracture will heal well, regain normal
function, and have legs that are equal in length. The intramedullary nails may need
to be removed following healing if they cause irritation of the skin and tissues
Occasionally, children will require further treatment, either early on or in subsequent
years, if they have a significant difference in the length of the legs, unacceptable
angulation of the healed bone, abnormal rotation of the healed bone, infection,
or (rarely) if a thighbone fracture persists (nonunion).
These problems can nearly always be resolved with further treatment.
In order to assist doctors in the treatment of thighbone fractures, the American
Academy of Orthopaedic Surgeons has done research to provide some useful guidelines.
These are only recommendations, and do not have to be followed specifically for
the treatment of your child's fracture.