Pigeon Toes (Intoeing)

In-toeing is most commonly seen in newborns and young children, and deformities and angular deviations of the lower extremities are one of the most prevalent causes for referral to pediatric orthopedics. A rotational change anywhere in the lower extremities causes the foot to point inward, which is known as pigeon-toeing.

Understanding the normal growth and development of children's lower extremities is crucial to understanding variational diseases of the lower limb. Femoral anteversion, or forward rotation of the femoral neck, is roughly 40 degrees in neonates. With time, the hip's enhanced internal rotation reduces.

The degree of anteversion diminishes by around half by the age of ten. Any variation from the usual course of limb development and rotation should be identified and distinguished from early angulation persisting and disorders that limit proper rotation.

Epidemiology

Metatarsus adductus is the most prevalent disease in children under the age of one year. It occurs in roughly 1% of all births, and it is more common in girls than in boys.

Internal tibial torsion is the most common cause of intoeing in children between the ages of one and four. There is no gender bias or identifiable cause.

The third most common cause of intoeing in children is increased femoral anteversion. This can occur during infancy, although it is most common after the age of three, with an average reporting age of three to six years. This is two-fold more common in males.

Intoeing Causes

Metatarsus adductus, internal tibial torsion, and femoral anteversion are the three most common etiologies of pediatric intoeing. Each has its own set of typical findings and presenting age.

Pathophysiology

Metatarsus adductus is characterized as angulation of the metatarsals toward the midline, creating the impression of a "C" shaped foot, and is ascribed to intrauterine positioning.

The tibia is generally internally rotated at birth, but the degree of angulation varies greatly.

Increased intrauterine pressures can potentially cause femoral anteversion, putting unnecessary pressure on growth sites. The greater trochanter is rotated posteriorly in these circumstances because the femur's neck is rotated inwards. Because there is a physiologic external rotation of the hip throughout toddler growth, the ensuing intoeing becomes increasingly noticeable with maturity.

Tibial Torsion

The most prevalent cause of intoeing is tibial torsion, which is an inward twisting of the tibia. It is most commonly found in children under the age of two. Males and females are equally afflicted, and roughly two-thirds of individuals are affected on both sides. Tibial torsion can last well into adulthood, resulting in patellofemoral disease.

The lateral rotation of the tibia normally rises from about 5o at birth to about 15o in maturity. While medial torsion improves over time, lateral torsion frequently increases as the natural progression is toward additional external torsion. The degree of inversion and eversion present in the foot, as well as the amount of rotation possible at the hip, determine the ability to adjust for tibial torsion. When the foot adducts due to internal torsion, the patient attempt to compensate by everting the foot, externally twisting the hip, or both. External tibial torsion causes people to invert their feet and internally rotate their hips.

Femoral torsion usually resolves by the time the patient reaches the age of 8-9 years. All remodeling will have happened by this age, and any additional correction will be due to a purposeful change in posture.

The normal femoral anteversion in a baby is 40 degrees, and by the age of eight years, it has decreased to 10 degrees. The acetabulum is 15 degrees forward. The risk of hip arthritis is not increased by femoral anteversion. Up to the age of eight years, spontaneous improvement in anatomic position can occur, and additional correction can be obtained by improving the gait by deliberate effort until puberty.

Because the disease has a benign natural history, with the majority of cases resolving on their own, observation with a yearly evaluation is usually all that is required for management. If the abnormality is more than three standard deviations from the mean, the osteotomy is recommended.

Epidemiology

Individuals in India were found to have less tibial torsion than Caucasians but roughly the same amount as the Japanese population in a study by Mullaji et al aimed at defining tibial torsion standards. Different lifestyles and postures of different populations, such as cross-legged sitting positions, are likely to create variances in normal tibial torsion levels.

Clinical Presentation

Details on the patient's age at onset, severity, disability, milestones, and family history should all be included in the history. Metatarsus adductus is the most common cause of in-toeing in children under the age of 18 months. Tibial torsion is the most prevalent ailment in children between the ages of 18 months and three years. Femoral torsion is the most prevalent diagnosis in children above the age of three.

Physical Examination

Other tests are usually not performed because the diagnosis is based on clinical findings. Tests to rule out hip dysplasia, hip and ankle ranges of motion, and knee varus or valgus, all of which can create obvious examination errors, must be performed. Imaging studies could be beneficial. However, imaging studies are not required for every child who is evaluated for torsional abnormalities.

In general, parents are more worried about intoeing than children. Severe intoeing can cause a youngster to misstep or run awkwardly, as well as obstructing sports participation and causing pain. Because the child uses the lateral border of the shoe as the presenting border of the foot on the playground, excessive wear is visible along the lateral border of the shoe, primarily in the front half.

The following are the components of a rotational profile:

• Angle of foot progression
• Thigh-foot angle, transmalleolar angle for tibial version or torsion
• Anteversion of the femur (hip rotation)
• The foot's shape

The Angle of foot progression is the angle difference between the foot's axis and the progression line. External rotation of 10-15 degrees is normal for Angle of foot progression. External rotation values are positive by convention, while internal rotation values are negative. The following are the several levels of in-toeing:

• –5 to –10° is considered mild.
• –10 to –15° is considered moderate.
• More than –15° is considered severe.

The degree of rotation of the tibia along its long axis from the knee to the ankle is known as the tibial version or torsion. The patient is measured lying down with his or her knees flexed to 90 degrees. Two tests, the Thigh-foot angle and the transmalleolar angle are used to assess it.

With the patient prone and legs flexed to 90 degrees, the Thigh-foot angle is measured from above, with the examiner focusing at the feet. It's the angle formed by the line of the thighs' axis and the line of the foot's axis. The outward rotation of a typical Thigh-foot angle is 10-15 degrees. External rotation values are positive by convention, while internal rotation values are negative.

The axis of the line connecting the two malleoli is known as the transmalleolar axis. The transmalleolar axis is outwardly rotated by 15-20°, as measured with reference to the coronal plane axis because the lateral malleolus is generally posterior to the medial malleolus. External tibial torsion is defined as a transmalleolar axis that is outwardly rotated more than 20 degrees, and internal tibial torsion is defined as a transmalleolar axis that is externally rotated less than 10 degrees.

The axial angle between the plane of the femurs' neck and the femoral condyles is known as femoral anteversion. It can be determined clinically by measuring hip rotation. External rotation should be between 46 and 70 degrees, and internal rotation should be between 10 and 45 degrees. Internal rotation increases as femoral anteversion increases, but external rotation decreases.

Tibial Torsion Diagnosis

A history and physical examination by the pediatrician are used to diagnose tibial torsion. During the evaluation, the physician obtains the child's complete gestational and birth history, as well as inquiries about any other family members who have been diagnosed with tibial torsion. In most cases, a diagnosis can be determined without the use of an X-ray.

Tibial Torsion Treatment

In most cases, orthotic treatment is unsatisfactory. The disorder has a generally positive prognosis. Because most cases settle on their own, surveillance with a yearly evaluation is usually sufficient. True metatarsus adductus is an intrauterine positional deformity that usually heals by the age of four years in 90% of instances. If no improvement is apparent, a lengthy leg cast can be used to remedy the problem. A weekly cast change is usually required for a period of 4-5 weeks.

If the deformity is more than three standard deviations from the mean, the osteotomy is recommended.  At any level, osteotomies can be performed.

If the deformity is more than three SDs from the mean and represents an aesthetic or functional issue, the osteotomy is recommended. Subtrochanteric, diaphyseal, and distal osteotomies are also possible. Distal osteotomies are less invasive and result in less blood loss and faster recovery.

There are no definite contraindications to treating tibial torsion as long as the indications for therapy are met. Borderline neurovascular status, poor skin health, and a high surgical hazard are all relative contraindications.

Another relative contraindication to correcting internal tibial torsion is a lack of inversion. The patient's capacity to position the foot down following external rotation correction is harmed by this problem. Patients who have had internal torsion for a long time trying to compensate by everting their feet. Internal tibial torsion can be countered by excessive hip external rotation combined with a lack of internal rotation, which is indicative of retroverted hips. Exceedingly externally rotated feet may result from tibial correction.

Femoral Anteversion

Femoral anteversion, also known as femoral torsion or femoral version, is the angle formed by the projection of two lines in the axial plane perpendicular to the femoral shaft, one through the proximal femoral neck area and the other through the distal condylar region, indicating the degree of femur twisting.  The biomechanics of the hip are affected by femoral anteversion because the moment arms and the course of action of muscles around the joint are changed. As a result, femoral anteversion is linked to gait abnormalities and is a potential risk for clinical issues such as osteoarthritis and slipped capital femoral epiphysis.

Femoral anteversion changes significantly during development, going from 0° in early pregnancy to 30° at delivery, then dropping to 15° in adulthood.  In addition to age, mechanical stress during movement appears to have a major influence on femoral anteversion, as various clinical disorders linked to delayed or impaired locomotion are linked to higher femoral anteversion.

Femoral Anteversion Causes

Although the specific reason is unknown, femoral anteversion is a congenital (existing from birth) condition that occurs when a child is in the uterus. It appears to be linked to the baby's location in the uterus while growing. It is thought that some people are genetically susceptible to the disease because it typically runs in families. This torsional abnormality can also emerge as a result of trauma. A torsional malunion can occur after a femur fracture, resulting in the same complications.

Femoral Anteversion Symptoms

The following are signs and symptoms of femoral anteversion:

• Walking pigeon-toed, with each foot pointing gently toward the other, is known as intoeing.
• Bowlegs (leg bowing). Maintaining balance by keeping the legs in this position is common.
• Hip, knee, and/or ankle pain are common.
• Walking makes a cracking sound in the hip.

Femoral Anteversion Diagnosis

In general, the doctor will go through the patient's medical history, perform a physical exam, and watch the patient's gait for evidence of intoeing. To rule out any deformities, the doctor may perform X-rays or a CT scan. Femoral anteversion, on the other hand, can be difficult to detect in some circumstances. This is especially true when the femoral anteversion is accompanied by a secondary rotational bone abnormality, such as external tibial torsion - a tibia that rotates outward. "Tetra-torsional malalignment," sometimes known as "miserable malalignment syndrome," is a term used to describe this type of complicated condition. It's difficult to diagnose because:

• The patient's feet remain parallel during stepping due to the two opposite rotations of the femur and tibia. This implies that the misalignment of the hips and knees may go undetected, even if the patient experiences pain or discomfort.
• Rotational abnormalities, which are on the axial plane and best visible from above, are not properly displayed by X-rays obtained from the front, back, or side.

Femoral Anteversion Treatment

Most children with femoral anteversion are treated by doctors who keep a careful eye on them for several years. The twisting of the thigh bone in most children corrects itself over time. By the time they are 9 to 10 years old, most youngsters have developed normal or near-normal walking patterns. Others, by the time they reach adolescence, have developed typical walking patterns.

Braces, special shoes, and exercises rarely aid or quicken the body's natural self-correcting femoral anteversion mechanism. However, if the child's feet are badly pointing inward or if the issue is not improving over time, the child's doctor may propose one of these therapies.

Twisting-in can be severe in some situations, and it may not self-correct by the time a child reaches the age of 8 or 9. Surgeons may conduct surgery to place the femur at a more normal angle in children with significant, unsolved femoral anteversion at that age.

The surgeon slices the femur, rotates the ball of the femur in the hip joint to a normal place, and reattaches the bone during the procedure.

Metatarsus Adductus

The metatarsus is a number of bones located within the middle of the foot. Each of the five metatarsal bones in each foot is attached to the toes' separated bones (phalanges). The metatarsal bones are bent toward the center of the body, which is known as metatarsus adductus. This leads to a clear malformation, which regularly affects both feet.

Metatarsus Adductus Causes

Metatarsus adductus has no recognized cause. There was no link discovered between gestational age at birth, mother age at birth, or birth order. According to one idea, the disease is attributed to the fetus being crammed inside the uterus during development. This could result in a foot anomaly and an inadequate posture.

Metatarsus Adductus Symptoms

You may observe that the child's foot has a bent form if he or she has metatarsus adductus. The forefoot (front half of the foot) points inward and can be somewhat bent under. The inside of the foot looks to be caved in, whilst the exterior of the foot appears to be more rounded. Unlike clubfoot, however, there is no foot drop.

Metatarsus Adductus Diagnosis

A physical exam can be used to diagnose metatarsus adductus. The high arch and a noticeably bent and split big toe are telltale indicators of this disease.

The degree of metatarsus adductus can be determined by measuring the range of motion of the foot. This condition is divided into two types: flexible and non-flexible. The foot can be manually stretched in a flexible metatarsus adductus. The non-flexible type has a rigid foot that does not return to its usual position when physical force is applied.

Metatarsus Adductus Treatment

In some situations of metatarsus adductus, stretching exercises may be indicated. In most kids, however, the problem resolves on its own. Treatment with casts or customized shoes may be required on occasion.

Surgery is rarely required; however, it may be suggested for children aged 4 and up who have a severe malformation. To remodel the foot, a variety of surgical techniques are available. All of them entail cutting particular bones (osteotomy) and then straightening them out with plates or screws.

The flexible metatarsus adductus usually lasts until one or two years of age. The foot returns to normal in the vast majority of cases. The foot remains moderately distorted in a tiny percentage of patients. Even after treatment, the foot can become rigid and misshapen in rare circumstances. Developmental dysplasia of the hip is more common in children with metatarsus adductus.

Conclusion

Lower leg disorders are rather frequent in children. Pigeon intoeing is a typical medical occurrence that is best handled by a multidisciplinary team that includes orthopedic nurses. Although pigeon intoeing might be unattractive, physicians should be aware that the vast majority of cases disappear as the kid grows older. The majority of instances are mostly addressed by observation, with a focus on parental reassurance. By the age of two, metatarsus adductus should have resolved, and any persistence is not linked to any symptoms. Serial casting should be considered for rigid and severe metatarsus adductus with no flexibility. Premature surgery has the potential to do more harm than benefit.