Bowlegs (Genu Varum)

Genu varum refers to legs that bow outward, commonly referred to as “bowlegs.” This is a normal occurrence in early childhood, as most of us are born with some degree of genu varum. The alignment becomes more apparent around the time we begin to stand and walk. With typical growth, the bowing straightens by 18 to 24 months of age.

There is not always a known cause for excessive genu varum. Metabolic bone diseases, such as rickets, with low vitamin D level can cause genu varum. Vitamin D supplementation can assist with leg alignment in these cases. Less common causes include genetic conditions that affect overall bone strength and growth, such as osteogenesis imperfecta, renal osteodystrophy and multiple epiphyseal dysplasia (MED) or spondyloepiphyseal dysplasia (SED).

If your child’s genu varum continues past 2 years of age or if the bowing is particularly severe, it is helpful to see a pediatric orthopedist for examination and x-rays. If there is disordered growth of the tibia just below the knee, called Blount’s disease, this can be treated with a brace to improve alignment over time. The brace typically must be worn for a minimum of 1 year to achieve the preferred alignment.

After 4 years of age, excessive genu varum often requires surgery to improve the leg alignment. This can be done with guided growth, where a plate and screws are placed around the outside of the knee and help the child’s growth to correct the alignment over time. Another option is an osteotomy, a surgery where sections of bone are removed to improve the alignment.