Ankle

CHILDREN’S FRACTURES – ANKLE
By:  Robert H. Sheinberg, D.P.M., D.A.B.F.A.S., F.A.C.F.A.S.

The ankle joint is made up of three bones called the tibia, fibula and talus.  At the end of the fibula and tibia there are growth plates.  This is the area of the bone which enables the bone to grow. 

These bones are connected by ligaments on the inner and outer side of the ankle.  They also have ligaments that connect the fibula and tibia together.

Tendons run along the inside and outside of the ankle.  They also are in the front and back of the ankle.  They allow motion to take place in the ankle joint.

Injuries to the ankle in children and teenagers can affect any of these areas.  However, the growth plates are the most vulnerable to injuries.  Injuries are also frequent to the ankle ligament.  However, because of their strength the growth plates which are weaker are more likely to fail first.

The tibia growth plate at the end of the bone counts for 15-20% of the length of the entire lower extremity.  Closure of this growth plate is usually completed by the age of 14 in girls and 16 in boys.  The fibular growth plate will close a little later.

Fractures of the tibia growth plate are more common between the ages of 8 and 15.  Fibula fractures are more common between the ages of 8 and 14.  Injuries to the ankle joint are more common during sporting activities.  Twisting injuries are most frequent.  However, direct hits to the bone via a kick to the side of the leg or hitting the foot hard on the ground may injure the growth plate.  They are also common in children on trampolines, bounce houses and those on bicycles or skateboards.

A child or teenager will usually present with immediate pain, swelling and tenderness that is diffuse throughout the ankle joint.  At times deformity may be present, which is indicative of a more severe growth plate injury.  The child or teenager will avoid all weight on the extremity.  Occasional numbness or tingling, which may be present on the outside of the foot, may be felt.  Difficulty moving the toes or foot at the ankle joint region are very common.  Immediate care is necessary to assess the injury and treat accordingly. 

X-rays:  X-rays are necessary to evaluate the injury to the joint.  If an x-ray is negative, however there is tenderness on the growth plate, treatment should be instituted to protect the area.  This is most commonly in the form of a boot or brace with crutches to protect the injured area.

If x-rays show that the injury is more severe, MRIs or CT scants may be necessary to more fully evaluate the injury.

Injuries to the growth plate may extend into the bone above the fracture or below into the joint.  In some cases the bone above the growth plate, into the growth plate and bone into the ankle joint will have been affected.

Treatment:  If a growth plate injury is nondisplaced, then cast immobilization either above or below the knee may be necessary to allow the area to heal.  Follow up x-rays within the first week are critical to ensure that displacement of the fracture and growth plate have not occurred.

Mild malalignment may require that the child or teenager is given a general anesthetic to allow the bone, growth plate and joint to be put into their normal anatomical position.  This position may be maintained with a cast.  In some cases placing a pin through the skin into the fracture site may be all that is necessary to stabilize an unstable fracture.

If there is more displacement of the bone and/or growth plate, then opening the area and anatomically reducing the fracture and placing in small pins or screws may be necessary to realign the area and allow complete healing.  Failure of closed reduction may be present because of interposition of soft tissue into the fracture site.  This tissue would preclude closed reduction and would predispose the child to a growth plate problem.  Postoperative casting would be necessary for 6-8 weeks.