Fractures of the hip, femur, knee, tibia, and ankle, are less common than those of the upper extremities, but are often more devastating injuries. This is because injuries to the lower extremity often temporarily impair your child from being able to walk. This may affect his/her ability to go to school or daycare, and often interferes with after-school activities and sports for your older child. Thankfully, most of these inconveniences are temporary as children have an enormous capacity for healing bones.

• Hip Fractures: If your child happens to sustain one of these fractures, this does not mean that your child has osteoporosis!  In fact, these injuries are quite rare in children because their bones are often very strong.  There are typically only two circumstances in which a child can sustain a hip fracture: 1) a high-energy injury such as a motor vehicle collision or being hit by a car, or 2) a low-energy injury in which the fracture occurs through a weak portion of the bone, usually a bone cyst.

The more common type of hip fracture occurs through a portion of the femur bone that has a rich blood supply.  They typically occur through a benign bone cyst that can occur in children. Many times, these fractures are fixed with a plate to allow your child to be up on his/her feet quickly after surgery. 

The less common type of hip fracture- that near the ball or neck of the femur bone, represents one of the only true fracture emergencies that a pediatric orthopaedic surgeon faces.  That is because the blood supply to the bone is temporarily compromised.  Although not proven, some believe that if the fracture is fixed early, it may decrease the chance that the blood supply is lost from the bone forever. Therefore, in certain situations, your doctor may fix this type of fracture in the middle of the night.

Regardless if the fracture occurs through the ball or neck of the femur or lower through a bone cyst, your physician will want to follow your child for a long time after the fracture – at least 18 months.  This is because it may take a long time for the loss of blood supply (known as avascular necrosis) to occur and/or, it may take a long time, but it is quite possible for a bone cyst to reoccur. 

• Femur (thigh bone) Fractures: These fractures are extremely common in children.  The treatment is based upon the age and size of your child as well as the location of the fracture.

In general, if your child is 4 years old or younger, then your physician will likely recommend a treatment in a cast known as a spica cast.  This cast starts near the nipple line, and extends the entire length of the fractured limb, and then the entire length or half the length of the other limb.  Please review the spica cast section for more information regarding care of your child in the spica cast.  Spica casts are applied in the operating room with your child completely asleep.  This is for two reasons.  First, moving around a broken femur bone is painful, and we do not want to cause your child any pain while applying this type of cast.  Second, the cast is quite big and difficult to apply, and your physician can do a much better job of applying a good cast with the bones lined up if your child is asleep.  Once the cast is on, your child wakes up, and many times can go home from the hospital the same day.  Some modifications you may need are straps for your car seat so your child can be transported safely, and you may also need a wheelchair if your child Is too big to fit in his stroller.  The hospital case managers will be able to help you get this equipment prior to your child being discharged from the hospital.  Most children are treated in a spica cast for a femur fracture for a total of six weeks.  Be prepared for your child to be upset when the cast comes off!  He has been “stuck” in one position for six weeks and can get quite stiff.  So, your child may perceive this stiffness as painful.  If your child normally walks, it may take a few days to a few weeks before he walks again, and when he does, he will walk with a limp.  It may take a few months for this limp to completely go away.  In addition, it is not uncommon for your child to have a rash on their skin with the cast is removed.  Just bathe your child with warm water – do not scrub as this will be painful.  You can apply a little bit of lotion.  In a few days, most of these rashes will clear up just fine.

For children 5 years of age and older, the treatment of the femur fracture is more dependent on the location of the fracture and the size of the child.  Most of the time, the surgeons at Children’s Orthopaedics of Atlanta use flexible rods to line up the broken ends of the femur fracture.  These rods are inserted into the femur bone near the knee.  The surgery is fairly minimally invasive, and most children recover quickly.  However, your child will need another surgery to remove the rods (usually 9-12 months after the injury).  Other times, a plate is used to fix the fracture, and then less commonly, a rod may be placed from the top of the femur bone and go all the way down – similar to how adults are currently treated.

• Fractures Around the Knee: There are several types of fractures that can occur around the knee.  Two of these involve growth areas – one of the bottom portion of the femur bone and one near the top portion of the tibia bone.  Please refer to growth plate fractures for further details on these injuries.  Two other more common types of fractures around the knee occur at areas know as either the tibia tubercle or the tibia spine
  
  
• Tibia tubercle fractures: These fractures typically occur if your child lands on a straight knee, such as jumping while playing basketball. The tibia tubercle is the bump under the knee where the large patella tendon inserts.  When this bump breaks, it often times needs to be fixed surgically so that the ability to straighten the knee is not compromised.  The fracture is typically repaired with a few screws, and your child is immobilized in either a cast or a knee brace with the knee held straight for approximately 6 weeks.  Once the cast is removed, physical therapy is often necessary to help strengthen the quadriceps muscle
  
  
• Tibial spine fracture:  This is a fracture of the bone in the knee where the anterior cruciate ligament (ACL) attaches.  These injuries most commonly occur after a child falls off a bicycle.  Occasionally, these fractures can be treated without surgery by holding the knee straight in a splint or a cast; however, if the fracture fragment does not line up perfectly, then your physician may recommend a surgery to place the bone in a better position.  Most of the times, the surgery can be done arthroscopically with very small incisions.  Once the fracture is healed, physical therapy is often necessary to help with the recovery.
  
  
• Tibia (shin bone) Fractures: Treatment of tibia fractures, as seen with the other fractures described, depends on both the age of your child, and the location and severity of the fracture.   Fractures can occur from a simple twist and fall in the young child, and they are so common, that they have the name “toddler fracture” associated with it.  These fractures heal very quickly.  Often time, your provider will place your child in a cast for about 3-4 weeks, and that is usually the only treatment necessary.

In older children, the force required to break the bone is greater, and it is more difficult to hold the fracture in place with just a cast; however, most of the time, a cast is all that is needed for treatment.  The time it takes for a tibia fracture to heal in an adolescent is much longer than a toddler.  While a toddler can be treated in a cast for 3-4 weeks, it often takes about 3 months of casting for a tibia fracture to heal in older children and adults. 

If the fracture cannot be held in a cast, your physician may advise a surgery to better align the bones.  Typically, some type of rod is placed inside the bone – either a series of 2 flexible rods, or 1 rigid rod that is used in adults.  It depends on if your child is still growing or not.  The single rigid rod is left in permanently while the flexible rods need to come out surgically approximately 1 year after surgery.

Once the fracture is healed, physical therapy is often necessary because the calf muscle becomes quite weak and the ankle is typically stiff.  Nevertheless, most children make a complete recovery without any consequences.

• Ankle Fractures: Ankle fractures are a common injury in children.  Most of the time, these “fractures” involve the growth area of the small fibula bone.  In children, the growth areas of bone are made of cartilage, and this cartilage is weaker than the bone as well as the surrounding ligaments.  So, while the average 25 year old female may “sprain” her ankle (i.e. injure a ligament), when she rolls her ankle in, a 10 year old female who did a similar thing would not sprain, but would rather, “break” the ankle at the growth area.  Thankfully, these common injuries heal quite readily with little consequence.  Growth arrest is extremely rare.  Most of the time, your child will be placed in either a walking boot or a short leg walking cast for several weeks, and when the cast if off, the bone is usually healed, and your child is ready to get back into activities as soon as the strength and range of motion improve.

The other types of ankle fractures also occur around the growth areas, but they can have more serious implications, such as surgery.  Please review the growth plate section for further details on these fractures.