Hi there-
Sounds normal (see below) but I would talk to your Pediatrician on the next visit to be sure:
What are knock-knees?
A standing child whose knees touch but ankles do not, is usually said to have knock-knees. During childhood, knock-knees are a part of normal growth and development. They usually become apparent when a child is 2 to 3 years old and may increase in severity until about age 4. If this condition does not appear until a child is 6 years of age or older, however, an underlying bone disease may be present.
During childhood, knock-knees usually develop as an effort to maintain balance, particularly when the child begins to walk or if the child's foot rolls inward or tuns outward. When a child has knock-knees, both knees usually lean inward to an equal degree. One knee, however, may "knock" less than the other, or may even remain straight.
Overweight children are most likely to develop knock-knees, because their developing bones and joints have trouble supporting their weight and they tend to lean inward. Knock-knees usually correct themselves by the time a child is five years old. Occasionally, however, they persist into adolescence.
Severe knock-knees usually wind up restricting a child's physical activities. The child cannot run easily and may not want to participate in sports or other physical activities. If knock-knees persist into adolescence, problems of appearance as well as physical activity may arise.
What causes knock-knees?
Knock-knees most often develop as a part of natural growth. Diseases, such as osteomyelitis (a disease of the bone) and rickets, may cause permanent knock-knees. Injury to the growth area of the tibia (shinbone) often impairs bone growth and may cause knock-knees. This injury usually occurs only in one leg, resulting in one knocked knee.
How are knock-knees diagnosed?
Knock-knees are obvious when a child stands with the legs straight and the toes pointed forward. A physician can determine the severity of knock-knees by observing the position of the child's legs, knees, and ankles, and by measuring the distance between the child's inner ankle bones: the greater the distance between the ankles, the more severe the condition. The physician will also take a complete medical history. X-ray films are usually taken to determine the severity of bone deformity.
How are knock-knees treated?
Specific treatment for knock-knees will be determined by your child's physician based on:
your child's age, overall health, and medical history
the extent of the condition
your child's tolerance for specific procedures, or therapies
expectations for the course of the condition
your opinion or preference
A mild case of knock-knees usually requires no treatment, since it often corrects itself. More severe knock-knees may require the use of orthopaedic appliances. Your child's physician may prescribe a night brace, particularly if a family history of knock-knees exists. A night brace is attached to a shoe and works by pulling the knee up into a straight position. Orthopaedic shoes, usually equipped with a heel wedge and occasionally an arch pad, may also be recommended.
If braces and shoes do not correct knock-knees, surgery may be recommended. The surgery may involve either influencing growth or cutting and straightening the bone. For the best results, surgery should be performed when a girl is bout 10 years old and a boy about 11. This allows time for the bones to straighten on their own.