What are the causes of knee deformities?
From the time children begin to walk until about 2 years of age, the legs are often bent or bowed, a phenomenon called genu varum. From the age of 3 years, the legs tend to adopt an x-shape, known as genu valgum. This posture is usually maintained until the age of 7 or 8, when the legs return to their normal position. Therefore, after the age of eight, any varus or valgus position (bracketed or X-shaped) is abnormal, and can be mild or severe. Fortunately, a small group of these alterations are due to common growth diseases. The genu valgum or x-legs decrease with growth, so the leg axis between 7 and 8 years of age becomes normalized.
What complications can be caused by knee deformities in children and adolescents?
Genu varum (bracketed legs) and genu valgus (X-legs) alter the mechanical axis of the knee, i.e. they overload the inner or outer part of the knee. This can lead to pain, meniscal lesions or osteoarthritis in adulthood.
What type of knee deformities can we find in children and adolescents?
For the professional it is important to differentiate two groups of deformities. Those that we would call postural deformities, which involve an exaggeration of posture and among which are the x-knees or bracketed knees. However, on radiological and general clinical analysis, we did not find any cause of bone development or any type of metabolic disease. In other words, these are healthy children with knees with this deformity. The other important group is pathological deformities. These are children who have deformed knees, in which there is an alteration in the growth of the knees or other joints of the body. They are alterations due to congenital or genetic disorders.
What treatments are available to correct knee deformities in children and adolescents?
The only reliable treatments are the surgical ones, which receive the generic name of hemiepiphysiodesis, and which allow the temporary or permanent blocking of one of the sides of the knee. Since 2007 we have had an advance for these treatments, known as guided growth control. This uses special tension plates with two screws that are placed through a small incision in the child’s knee without damaging the growth plate. The child remains in the hospital for one day, starts walking the next day, and after 15 days can lead a normal life. Every four months the improvement of the posture of the knees is controlled in the office. When we are sure that the correction is complete, by means of a small incision in the same wound, the plates are removed and the growth continues unaltered. An advantage of this type of treatment is that it allows the treatment of young children and children with growth plate disease.