Torsional Deformity

What Is It?

The dictionary defines "pigeon-toed" as "having the toes turned inward." No such colorful term can be found for feet that point outward. These foot problems can be caused by a problem that doctors call torsional deformities. This is when the long bones of the leg are turned to the inside or outside so that the toes of the feet do not point straight ahead. Either of the two main bones in the leg can be affected — the femur (between the hip and the knee) or the tibia (the larger of the two bones between the knee and the ankle). One or both legs can be affected.

Torsional deformities can lead to toes that point inward (in-toeing) or toes that point outward (out-toeing). Parents often worry that in-toeing or out-toeing will permanently interfere with their child's ability to walk and run normally. However, in most young children, in-toeing or out-toeing is caused by a torsional deformity that appears for a short period of time, and then disappears during the normal stages of leg development. Most torsional deformities are temporary, and correct themselves by age 6 to 8. In rare cases, in-toeing or out-toeing is a sign of a permanent bone deformity or other problem that requires medical attention.

These conditions may be related to one or more of the following factors:

• The child's position in the uterus before birth
• An inherited family tendency for in-toeing or out-toeing
• Sitting or sleeping in certain positions for prolonged periods, for example, during long hours of watching television

The most common type of torsional deformity in toddlers is when the tibia (in the lower leg) is rotated inward, leading to in-toeing. This is caused by the child's position in the uterus before birth, and usually is seen in children younger than 2. As the body works to correct this problem during development, the tibia sometimes can turn too far in the opposite direction and become rotated outward. This can cause out-toeing, but the condition usually is temporary and will go away as the child develops.

The most common cause of in-toeing in older children is when the femur (in the upper leg) is rotated inward. This is more common in girls than boys, and usually is seen in children 3 to 6 years old. In most cases, the cause is unknown. Some experts believe that it is an inborn problem related to a child's position in the uterus before birth. Others blame it on a child's position while sitting or sleeping. For example, children seem to be at higher risk of developing this problem if they frequently sit with their knees pointed forward and touching and their legs folded under, splayed to either side (in the "W" position). In rare cases, this condition is caused by neuromuscular disorders, such as cerebral palsy.

Out-toeing due to an abnormal outward rotation of the femur is uncommon. The cause of this condition is unknown, but it probably is related to positioning of the legs before and after birth, and usually affects both legs. In rare cases, out-toeing is seen in only one leg and may be a sign of a serious problem with the upper part of the femur bone called slipped capital femoral epiphysis (SCFE).