Definition

Bowlegs is a condition in which the knees stay wide apart when a person stands with the feet and ankles together. It is considered normal in children under 18 months.

Alternative Names

Genu varum

Causes

Infants are born bowlegged because of their folded position in the mother's womb. Bowed legs begin to straighten once the child starts to walk and the legs begin to bear weight (about 12 to 18 months old).

By around age 3, the child can most often stand with the ankles apart and the knees just touching. If the bowed legs are still present, the child is called bowlegged.

Bowlegs may be caused by illnesses, such as:

• Abnormal bone development
• Blount disease
• Fractures that do not heal correctly
• Lead or fluoride poisoning
• Rickets, which is caused by a lack of vitamin D

Symptoms

Symptoms may include:

• Knees that do not touch when standing with feet together (ankles touching)
• Bowing of legs is same on both sides of the body (symmetrical)
• Bowed legs continue beyond age 3

Exams and Tests

A health care provider can often diagnose bowlegs by looking at the child. The distance between the knees is measured while the child is lying on the back.

Blood tests may be needed to rule out rickets.

X-rays may be needed if:

• The child is 3 years old or older.
• The bowing is getting worse.
• Bowing is not the same on both sides.
• Other test results suggest disease.

Treatment

No treatment is recommended for bowlegs unless the condition is extreme. The child should be seen by the provider at least every 6 months.

Special shoes, braces, or casts can be tried if the condition is severe or the child also has another disease. It is unclear how well these work.

At times, surgery is done to correct the deformity in an adolescent with severe bowlegs.

Outlook (Prognosis)

In many cases the outcome is good, and there is most often no problem walking.

Possible Complications

Bowlegs that does not go away and is not treated may lead to arthritis in the knees or hips over time.

When to Contact a Medical Professional

Contact your provider if your child shows ongoing or worsening bowed legs after age 3.

Prevention

There is no known way to prevent bowlegs, other than to avoid rickets. Make sure your child is exposed to sunlight and gets the proper amount of vitamin D in their diet.

References

Sheffer BW. Osteochondrosis or ephiphysitis and other miscellaneous affections. In: Azar FM, Beaty JH, eds. Campbell's Operative Orthopaedics. 14th ed. Philadelphia, PA: Elsevier; 2021:chap 32.

Winell JJ, Baldwin KD, Wells L. Torsional and angular deformities of the limb. In: Kliegman RM, St. Geme JW, Blum NJ, Shah SS, Tasker RC, Wilson KM, eds. Nelson Textbook of Pediatrics. 21st ed. Philadelphia, PA: Elsevier; 2020:chap 695.