Bow-legged (Genu Varum)
Almost all babies are born bow-legged. At birth, the soles of a baby's feet face each other with the tibia and femur curved outwards. There is also a space between the knee joints. During the first year of life, the knee joints move closer together, the femur slopes downward and inward toward the knee, the tibia straightens and the soles of the feet point down. During this process, the bones ossify or harden as they change from cartilage to bone. By the time babies begin to walk, the leg bones have hardened and straightened to allow walking.
There is usually little or no effect on the ability to walk for those with genu varum. Children usually have no symptoms, while adults may feel some discomfort on the outside of their knees. If left untreated, however, uneven stress and wear on the knees often leads to the early onset of arthritis. Visually, the legs of those with genu varum are bowed outward.
Causes and Risk Factors
The most common cause of genu varum is rickets or any condition that prevents bones from forming properly. Skeletal problems, infection and tumors can affect the growth of the leg, which can cause one leg to be bowed. Arthritis, if it affects the inside of the knee more than the outside can lead to bowed legs, as can a fracture that does not heal properly. Some professions, such as jockey, can lead to bow-leggedness, as can physical trauma.
A physical examination and an X-ray are used to confirm the diagnosis of genu varum, as well as to determine the condition of the bones and joints. A device called a goniometer is used to measure the degree of abnormal bowing.
If caused by rickets, the underlying disease is treated while the child is never placed on its feet. Vitamin D is prescribed to treat rickets and, thereby, to resolve the bowing of the legs. This usually leads to a correction of the deformity, although splints can be used to increase the speed of the cure.
In older patients, the only treatment is surgery. After surgery, patients wear braces or casts until the legs heal. Physiotherapy is usually prescribed to regain full range of motion and strength in the legs.