Clubfoot

Clubfoot is a birth defect where one or both feet are rotated inward and downward. The affected foot and leg may be smaller than the other. In about half of those affected, both feet are involved. Most cases are not associated with other problems. Without treatment, people walk on the sides of their feet, which causes problems with walking. Clubfoot is a birth defect where one or both feet are rotated inward and downward. The affected foot and leg may be smaller than the other. In about half of those affected, both feet are involved. Most cases are not associated with other problems. Without treatment, people walk on the sides of their feet, which causes problems with walking. The exact cause is usually unclear. A few cases are associated with distal arthrogryposis or myelomeningocele. If one identical twin is affected, there is a 33% chance the other one will be as well. Diagnosis may occur at birth or before birth during an ultrasound exam. Initial treatment is most often with the Ponseti method. This involves moving the foot into an improved position followed by casting, which is repeated at weekly intervals. Once the inward bending is improved, the Achilles tendon is often cut, and braces are worn until the age of four. Initially, the brace is worn nearly continuously and then just at night. In about 20% of cases, further surgery is required. Clubfoot occurs in about 1 in 1,000 newborns. The condition is less common among Chinese and more common among Māori people. Males are affected about twice as often as females. Treatment can be carried out by a range of healthcare providers and can generally be achieved in the developing world with few resources. In clubfoot, one or both feet are rotated inwards and downwards. The affected foot, calf, and leg may be smaller than the other. In about half of those affected, both feet are involved. Most cases are not associated with other problems. Without treatment, people walk on the sides of their feet, which causes issues with walking. There are many hypotheses about how clubfoot develops. Some hypothesis include: environmental factors, genetics, or a combination of both. Research has not yet pinpointed the root cause, but many findings agree that 'it is likely there is more than one different cause and at least in some cases the phenotype may occur as a result of a threshold effect of different factors acting together.' Some researchers hypothesize, from the early development stages of humans, that clubfoot is formed by a malfunction during gestation. Early amniocentesis (11–13 wks) is believed to increase the rate of clubfoot because there is an increase in potential amniotic leakage from the procedure. Underdevelopment of the bones and muscles of the embryonic foot may be another underlying cause. In the early 1900s, it was thought that constriction of the foot by the uterus contributed to the occurrence of clubfoot. Underdevelopment of the bones also affects the muscles and tissues of the foot. Abnormality in the connective tissue causes 'the presence of increased fibrous tissue in muscles, fascia, ligaments and tendon sheaths'. Mutations in genes involved in muscle development are risk factors for clubfoot, specifically those encoding the muscle contractile complex (MYH3, TPM2, TNNT3, TNNI2 and MYH8). These can cause congenital contractures, including clubfoot, in distal arthrogryposis (DA) syndromes. Clubfoot can also be present in people with genetic conditions such as Loeys–Dietz syndrome.