Clubfoot is a birth defect where one or both feet are rotated inward and downward. Congenital clubfoot is the most common congenital malformation of the foot with an incidence of 1 per 1000 births. In approximately 50% of cases, clubfoot affects both feet, but it can present unilaterally causing one leg or foot to be shorter than the other. Most of the time, it is not associated with other problems. Without appropriate treatment, the foot deformity will persist and lead to pain and impaired ability to walk, which can have a dramatic impact on the quality of life.

The exact cause is usually not identified. Both genetic and environmental factors are believed to be involved. There are two main types of congenital clubfoot: idiopathic (80% of cases) and secondary clubfoot (20% of cases). The idiopathic congenital clubfoot is a multifactorial condition that includes environmental, vascular, positional, and genetic factors. There appears to be hereditary component for this birth defect given that the risk of developing congenital clubfoot is 25% when a first-degree relative is affected. In addition, if one identical twin is affected, there is a 33% chance the other one will be as well. The underlying mechanism involves disruption of the muscles or connective tissue of the lower leg, leading to joint contracture. Other abnormalities are associated 20% of the time, with the most common being distal arthrogryposis and myelomeningocele. The diagnosis may be made at birth by physical examination or before birth during an ultrasound exam.

The most common initial treatment is the Ponseti method, which is divided into two phases: 1) correcting of foot position and 2) casting at repeated weekly intervals. If the clubfoot deformity does not improve by the end of the casting phase, an Achilles tendon tenotomy can be performed. The procedure consists of a small posterior skin incision through which the tendon cut is made. In order to maintain the correct position of the foot, it is necessary to wear an orthopedic brace until 5 years of age.

Initially, the brace is worn nearly continuously and then just at night. In about 20% of cases, further surgery is required. Treatment can be carried out by a range of healthcare providers and can generally be achieved in the developing world with few resources.

Clubfoot occurs in 1 to 4 of every 1,000 live births, making it one of the most common birth defects affecting the legs. About 80% of cases occur in developing countries where there is limited access to care. Clubfoot is more common in firstborn children and males. It is more common among Māori people, and less common among Chinese people.