Management of bow legs in children: A primary care protocol

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Original Research

Management of bow legs in children: A primary care protocol

J Fam Pract. 2017 May;66(5):E1-E6

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References

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In our study, only 3% of children with physiologic genu varum presented at 24 months of age or older, compared with 20% of Blount’s disease patients. We recommend considering orthopedic referral for any patient presenting with bow legs at 24 months of age or older. Additionally, consider orthopedic referral for any patient whose varus has not begun to correct within 8 months or has not resolved within 14 months of presentation, as more than 95% of patients with physiologic genu varum are expected to meet these milestones (TABLE 1). And do not hesitate to refer patients at any stage of follow-up if you suspect pathology or if parents are anxious.

If no sign of pathology is immediately identified, we recommend the following course of action:

Record a reference fingerbreadth or ruler measurement at the initial presentation.
Re-examine the knee varus at the next regular well-child visit (TABLE 5).

In our study, only 3% of children with physiologic genu varum presented at 24 months of age or older, compared with 20% of Blount's disease patients.Re-examining the patient prior to the next well-child visit is unnecessary, as some degree of bowing is typical until age 18 to 24 months.^{1,6,7,9,12,13,17} Recommend orthopedic referral for any patient with varus that has progressed since initial presentation. Without signs of pathology, repeat varus assessment at the next well-child visit. This schedule minimizes the need for additional physician appointments by integrating follow-up into the typical well-child visits at 18, 24, 30, and 36 months of age.³² The 6-month follow-up interval was a feature of our study and is recommended in the related literature.¹²

Consider orthopedic referral for patients whose varus has not corrected by the second follow-up appointment, as more than 95% of patients should have measurable varus correction at this visit. Most patients will have exhibited varus resolution by this time and will not require additional follow-up. For patients with observable correction who do not yet meet the criteria for resolution, we recommend a third, final follow-up appointment in another 6 months.
Refer any patient whose varus has not resolved by the third follow-up appointment, as more than 95% of genu varum cases should have resolved by this time. This finding is echoed in the literature; any varus beyond 36 months of age is considered abnormal and suggestive of pathology.^5,7,8,13,14 If evidence of Blount’s or skeletal dysplasia is identified, orthopedic management will likely consist of bracing (orthotics) or surgical management.

CORRESPONDENCE
Dennis S. Weiner, MD, Department of Orthopedic Surgery, Akron Children’s Hospital, 300 Locust Street, Suite 250, Akron, OH, 44302; mdicintio@chmca.org.

ACKNOWLEDGEMENTS
The authors thank Meadow Newton, BS, assistant research coordinator, Akron Children’s Hospital, for her editing and technical assistance and Richard Steiner, PhD, The University of Akron, for his statistical review.