Most people's feet point straight ahead or slightly outward. Some people's feet, however, point inward ? a musculoskeletal condition referred to as in-toeing. In-toeing affects infants and children and is characterized by an inwardly rotated foot or feet, or, less often, an outwardly rotated foot or feet (sometimes called out-toeing ). Doctors may also refer to this as a ?rotational problem' of the lower extremity, which can arise from abnormalities in the growth or alignment of the upper legs, lower legs, or feet. The vast majority of such problems, however, represent simply a physiological variation during a normal stage of development. As a result, a child may be ?pigeon-toed,' or, alternatively, one or both feet appear splayed outwards. Depending on the specific cause of the condition, in-toeing may appear at different ages, from birth to adolescence.
There are three common causes of in-toeing: (1) medial femoral torsion (also called femoral anteversion ), in which the femur, or thighbone, is rotated inward; (2) medial tibial torsion (also called internal tibial torsion ), which is marked by an inwardly rotated tibia or shinbone in the lower leg; and (3) metatarsus adductus, in which the foot is bent inward like a kidney bean.
Out-toeing is much less common than in-toeing, but is caused by similar problems.
The upper portion of the leg consists of a single bone called the femur , or thighbone. The top of the femur inserts into the pelvis to form the hip joint, which is a ball-and-socket joint. The bottom of the femur connects to the lower portion of the leg at the knee joint, which is a hinge joint. The lower leg consists of two bones, the tibia and the fibula . The tibia is the shin bone, which is the larger of the two bones, bears most of the weight placed on the lower leg, and is located to the inside of the fibula. The other leg bone is the fibula , which is a thinner bone located to the outside of the tibia and runs parallel to it.
The foot has a complex musculoskeletal structure, consisting of 7 bones in the base of the foot, known as tarsal bones , 5 bones in the middle portion of the foot, called metatarsal bones , and a series of 14 small bones, or phalanges , which comprise the toes. The bones are attached to each other and to the lower leg bones by an integrated meshwork of thick, fibrous structures known as ligaments . The areas in which two bones make contact with each other are lined with smooth cartilage coated with a natural lubricating material known as synovial fluid , allowing them to slide past each other with minimal friction. These areas are the joints , and there are many joints in the foot, which collectively allow for movement in the foot and ankle.
When a fetus is developing in the womb, the lower limbs initially point outward, then begin rotating inward around the seventh week. However, this rotation causes the toes to point towards each other. During the rest of fetal development, the legs gradually rotate laterally again. This lateral rotational growth continues slightly during childhood, but by the time of birth, the feet are approximately pointed straight forward. A small amount of rotation in infant legs is considered within the range of normal growth variation and is referred to as version. An abnormal amount of rotation is termed torsion .
In healthy children, in-toeing is caused by three conditions. They are metatarsus adductus, internal tibial torsion, and increased femoral anteversion:
As described above, in-toeing or out-toeing may begin to manifest itself at different ages, depending on the underlying musculoskeletal cause of the condition. When a rotational problem of the lower extremities is suspected, a complete physical examination will be performed to evaluate the severity of the condition and its cause, and to ensure that no other deformities or orthopaedic conditions are present. An assessment known as the rotational profile (also called the torsional profile ) will also be performed, which involves taking six different measurements of the angles of the feet, legs, and hips when the child is in various positions and when walking or running. This allows for detection of isolated abnormal angles and facilitates identification of the cause of the rotational problem. X-rays of the legs and feet will also be taken to assist with definitive diagnosis and treatment planning. More sophisticated radiographic imaging techniques, such as a CT (computed tomography) scan and MRI (magnetic resonance imaging), are sometimes performed as well.
Rotational problems are common in infants and children. However, the majority of deformities are minor, will not cause functional deficiencies, and will resolve on their own. Operative treatment is rarely necessary. Children with in-toeing or out-toeing go on to have no limitations in their activities, from simple outdoor games to competitive sports. Therefore, although rotational problems may present some early challenges for children and parents alike, parents can expect their child to live a normal, active, and healthy life.
Naturally, you may have other questions about in-toeing or out-toeing that are not answered in the above summary. As your orthopaedic surgeons, we welcome any and all questions you may have, which we urge you to pose during your next office visit. We have listed several additional websites below that further explain in-toeing and out-toeing and some of the services and support groups available to children with these conditions and their parents: