Definition and Causes of Knock Knees
If a child’s knees touch when she’s standing, but her ankles do not, she is said to have knock knees. (1) When the knees are “pointing” or curved in towards each other, that leaves a larger-than-normal gap between the feet and ankles. A gap of up to 10 cm or 4 inches between the feet when the child is standing is considered normal.
Knock knees during childhood is considered a normal part of a child’s growth and development. (1) In fact, most children have bow legs until about age three due to the legs being folded inside the womb. Knock knees usually appear around age two or three and often increase in severity until about age four. By age six or seven, the legs normally straighten and align. (2)
“The condition is slightly more common in girls, although boys can develop it too.” (1)
Treatments for Knock Knees
“Knock knees usually correct themselves by the time a child is 7 or 8 years old. Occasionally, the condition persists into adolescence.” (1)
If you see any of the following symptoms in your child, she should be taken to see a doctor:
• A gap between her ankles greater than 10 cm or 4 inches
• A big difference between the angle of her lower legs when standing straight
• An excessive inward or outward knee angle
• Knee pain due to the angle of her knees
• Difficulty walking or awkward gait (2)
• Only one side appears affected
• Unusually short height for her age (3)
How Knock Knees can Affect a Child’s Growth and Development
As already mentioned, knock knees during childhood are considered normal, though some cases are severe enough that measures need to be taken to improve a child’s gait and ability to run, and to reduce the pressure of the misalignment and the related pain experienced by other supporting joints (hips, back, ankles).
If the condition appears when a child is 6 years of age or older, there may be an underlying bone disease that will require treatment. (1)
If your doctor determines that an underlying condition such as rickets or scurvy is the cause, the condition will need to be treated. Rickets is usually treated with vitamin D and calcium supplements. Scurvy is usually treated with vitamin C supplements. (2)
In cases where knock knee is the result of an inherited bone deformity, corrective surgery may be recommended to address the pain and alleviate related mobility issues. (2)
If a child is obese, losing weight will help alleviate hip and back pain.
Sources:
1) Knock knees. Boston Children’s Hospital. Web. Sept 11, 2013.
http://www.childrenshospital.org/az/Site1103/mainpageS1103P0.html
2) Knock knee. National Health Services. Web. Sept 11, 2013.
http://www.nhs.uk/conditions/knock-knee/Pages/Introduction.aspx
3) Bowlegs and Knock-Knees. American Academy of Pediatrics. Web. Sept 11, 2013.
http://www.healthychildren.org/English/health-issues/conditions/orthopedic/pages/Bowlegs-and-Knock-Knees.aspx?nfstatus=401&nftoken=00000000-0000-0000-0000-000000000000&nfstatusdescription=ERROR%3a+No+local+token
4) Ask the Expert: Dr. Austin Fragomen, Orthopedic Surgeon, Answers Your Questions on Knock Knees. Hospital for Special Surgery. Web. Sept 11, 2013.
http://hss.edu/onthemove/ask-the-expert-dr-austin-fragomen-orthopedic-surgeon-answers-your-questions-on-knock-knees/#.UjB7zT8oFDk
Reviewed September 11, 2013
by Michele Blacksberg RN
Edited by Jody Smith