Femur (Thighbone) Shaft Fracture

Description

The femur (thighbone) is the largest and strongest bone in the body, forming part of the hip above and the knee below. A femoral shaft fracture is a break in its long middle portion. Because the bone is so strong, breaking it usually takes a significant force.

How it happens (the mechanism)

In older children and teens, these come from high-energy events — a fall from a height, a sports collision, or a car crash. In toddlers and young children, a fall or a twisting injury can be enough. In a baby who is not yet walking, a thighbone fracture is unusual and prompts a careful, routine look at exactly how the injury happened, simply because this bone is so hard to break.

The good news is that a child’s thighbone heals fast and remodels strongly with growth — so the pieces do not need to line up perfectly, and a small amount of overlap is sometimes even welcome, because the injured bone tends to grow a touch faster for a year or two and evens out any minor shortening.

Symptoms

A painful, swollen, often crooked thigh, with the child unable or unwilling to bear weight; younger children may simply refuse to move the leg.

Doctor examination and imaging

The doctor checks the skin, the circulation and feeling of the leg and foot, and whether the break reaches toward the hip or knee. X-rays of the whole femur, including the hip and knee, show the fracture.

Treatment

Treatment depends heavily on age and size. Babies and toddlers are usually treated in a spica cast (around the waist and leg), which holds the bone while it heals quickly at that age. School-age children often do best with flexible rods placed inside the bone; teenagers are usually treated with a rod or a plate. We also keep an eye on leg lengths for a while after healing.

Recovery and long-term outlook

Most children heal within months and return to full activity. Temporary limping is common, and minor differences in length or angle usually remodel with growth.

When to call the doctor

Seek prompt care for severe or worsening hip, thigh, or knee pain, an inability to move or bear weight on the leg, or a foot that becomes numb, pale, or cold. Remember that pain felt at the knee can actually come from the hip, so a limping child with knee pain deserves to have the hip checked.

Learn more

OrthoInfo (AAOS) — Thighbone (Femur) Fractures in Children: orthoinfo.aaos.org

This information is for educational purposes only. It is not a substitute for professional medical advice, diagnosis, or treatment. For specific concerns about your child, consult a board-certified, fellowship-trained pediatric orthopaedic surgeon.