Physical Address
304 North Cardinal St.
Dorchester Center, MA 02124
Clubfoot (Talipes Equinovarus) and Clenched Hands
Introduction
Congenital contractures in the newborn are actually common, ranging from 1 : 100 to 1 : 200 for some types of contractures that include clubfeet, hip dislocations, and multiple congenital contractures (MCCs). Talipes equinovarus or clubfoot is an abnormality of the foot position. It may be positional, an isolated abnormality, or part of a larger constellation of abnormalities as seen in many genetic syndromes. Clubfoot resulting from in utero positional forces, as may occur with prolonged severe oligohydramnios, multiple gestations, or breech presentations, is not a “true” clubfoot in that the deformity can usually be corrected by manual postnatal manipulation of the foot. Congenital clenched hands are part of MCC syndromes. Fetuses presenting with clubfeet or clenched hands, particularly with more than one joint involved, warrant thorough investigation even if there is a possibility of uterine constraint as an etiology, because constraint is a rare primary cause of contractures, particularly multiple contractures.
Disorder
Definition
Clubfoot describes a range of abnormalities in which the foot is fixed in a plantar-flexed position, and the sole is rotated inward ( Chapter 65 ). The deformity may be unilateral or bilateral and affects the bony, muscular, tendinous, and ligamentous structures. Manual manipulation of the extremity does not correct the defect. Clenched hands typically refer to abnormal posturing that can include abnormal positioning of the arms, elbows, wrists, and fingers. Similarly, bony, muscular, tendon, and ligamentous processes are affected in the upper limb.
Prevalence and Epidemiology
Clubfoot occurs in approximately 1 : 1000 pregnancies and is more common in male fetuses (2 : 1 male-to-female ratio). There is an increased incidence among first-degree relatives. Ethnic variations in frequency exist; it appears to be less common in Asians (0.5 : 1000) and more common in the Polynesian islands (7.5 : 1000 births).
Etiology, Pathophysiology, and Embryology
Many cases of clubfoot, particularly unilateral, are isolated and not associated with other structural or genetic abnormalities. Clubfoot is commonly classified according to intrinsic or extrinsic causes. External forces that deform an otherwise normally developing foot are considered to be extrinsic causes of clubfoot, though controversy exists on the extent of the importance of extrinsic forces on the development of clubfeet, particularly bilateral. While many clubfeet are thought to be isolated, there is compelling evidence from familial and twin studies that there is a higher prevalence of congenital clubfeet in first-degree relatives. Isolated clubfeet have been shown to result from heterozygosity for mutations in the gene encoding PITX1 , thus supporting that some isolated cases of clubfeet result from single gene mutations, though the incidence of single gene disorders among isolated club feet is small. It is estimated that 20% to 25% of clubfoot cases are associated with syndromic etiologies such as MCC, congenital myopathies such as myotonic dystrophy, myelomeningocele with secondary neurologic involvement, amniotic band sequence, and chromosomal syndromes. Other etiologies that increase the risk of clubfeet include maternal smoking. It is critical to recognize that more than 400 genetic disorders are associated with congenital contractures, where the only manifestation of disease in utero may be clubfeet or clenched hands. It is important to recognize that MCC or arthrogryposis, is a highly heterogeneous group of disorders that can affect just the upper limbs, the lower limbs, or both. The most prevalent form of MCC is amyoplasia, accounting for one-third of all cases. It is a sporadic disorder that also has a specific natural history, and the underlying causes are unknown but thought to be vascular in origin.
You're Reading a Preview
Become a Clinical Tree membership for Full access and enjoy Unlimited articles
If you are a member. Log in here
