Congenital absence of both lower leg and foot is a condition characterized by the absence of these structures at birth, resulting in significant differences in limb formation. It is a disorder of limb development that is usually apparent soon after birth since the affected limb is visibly missing or underdeveloped. Although the exact cause remains unclear, the precise genetic basis is under investigation, and it may involve a combination of genetic and environmental factors. Because no specific prevalence data have been established, it is understood that this condition is uncommon and its occurrence varies across different populations.

The clinical presentation of congenital absence of both lower leg and foot is evident at birth with the noticeable absence of the limb structures. Infants are typically diagnosed based on the physical examination, as the condition presents with the lack of a fully formed lower leg and foot. In some cases, there may be additional differences in the development of the surrounding tissues or neighboring bones, although individual experiences can vary widely. Not all individuals experience all features, and severity varies considerably, meaning that some may have relatively isolated limb absence while others might experience related orthopedic challenges.

The precise genetic basis of congenital absence of both lower leg and foot is under investigation, and current evidence suggests it may result from complex genetic and environmental factors rather than a single gene defect. No specific genes have been definitively linked to this condition according to the available data, and there is no established inheritance pattern. This uncertainty means that the condition does not yet have a clearly defined familial transmission, and family history is not consistently observed. Genetic counseling may help families explore these uncertainties and understand that while a hereditary role cannot be completely ruled out, a clear pattern has not been documented.