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Bowleg and Knock Knees
What is bowleg?
Bowleg is a term used to describe outward curving of the legs that occurs in almost all children. Also known as genu varum, this is part of normal development. It is actually abnormal for children less than 18 months of age not to be bowleg.
Bowlegs, knock knees and the normal growth processBecause of their folded position in the uterus, normal children are born bowlegged. This actually increases until the age of 18 months, and then the legs straighten on their own.
By the time a child reaches age 3 or 4, they develop a knock-kneed configuration, in which their legs angle inwards.
This knock-kneed configuration straightens by about age six, leaving the normal slightly knock-kneed adult alignment. All of this is part of normal development in children, and if your child is on this schedule he or she requires no treatment. We do not use surgery, braces, therapy or special shoes as long as your child is within this normal range
When is alignment not normal?Very occasionally, children can have other problems that result in an abnormal alignment. Some of these problems relate to serious injuries, problems with metabolism or nutrition, or other orthopaedic problems such as Rickets or Blount's disease.
Causes of bowlegBowleg can be caused by rickets, Blount's disease, trauma, a fracture healing incorrectly, and genetic bone growth abnormalities. Bowleg, when it is not a part of normal development or due to trauma, is a symptom of a disease and not a disease itself.
If the child maintains bowlegs after 24 months of age, if the bowlegs are severe or much worse on one side, or if other problems are present, we will recommend an X-ray for better evaluation.
Diagnosing bowlegIn order to diagnose bowleg the doctor must examine the legs and knees. A person with bowleg will have legs that appear farther apart than normal. The distance between the knees while the child is lying on his or her back is a clinical measurement of genu varum. An instrument called a goniometer can be used to determine if the angle of one or both knees is abnormal, and the condition can be confirmed by joint X-rays, although they may not be necessary. Internal tibial torsion can complicate the bowleg diagnosis. Internal tibial torsion, also known as medial tibial torsion, is an inward twist of the tibia bone (shin bone at the front of the lower leg). This condition can make bowleggedness appear worse than it really is.
Treating bowlegAgain, the huge majority of children with bowlegs are absolutely normal and require no treatment. In unusual circumstances, however, we may diagnose your child with a different problem and recommend orthotic braces, special shoes, casts, or surgery if their condition worsens. If bowleg is left untreated, it can cause osteoarthritis or trouble walking as the child ages.
What is knock knees?In knock knees, the lower legs bend outward, such that when the knees are touching the ankles are spread apart. Knock knees is also known as genu valgum and is possible in one or both legs.
Normal leg developmentMost children are born bowlegged and remain that way until about age 2 or 3. At that point, they develop the knock-kneed configuration, which persists until about age 6. Adolescents and adults are usually slightly knock-kneed.
Diagnosing knock kneesThere is normally no pain associated with knock knees. It is diagnosed by watching how the child walks and measuring the angle at which the ankles point outward. The physician may also order X-rays if an underlying bone problem is suspected.
Causes of knock kneesKnock knees usually develops as part of normal growth, but it may also be due to a disease such as rickets or osteomyelitis. Injury to the shin bone can cause knock knees as well. Obesity is an additional risk factor.
Coping with knock kneesKnock knees is usually not treated because the child grows out of the condition; certain exercises can make the knee stronger, which helps to stabilize the it. In rare cases surgery may be recommended to correct extreme knock knees that cause immediate pain or difficulty walking, or that will cause arthritis later in life. Surgery is usually done at about age 10 or 11, before the child stops growing. It involves fusing or placing pins at certain growth plates so that growth may be restricted in areas that are growing faster than others. Bracing or orthopaedic shoes may also be recommended.
