In CTEV, they overlap and face laterally, aligning toward the fifth metatarsal. In the lateral view, again the talus and calcaneus in CTEV appear to be parallel. In the normal foot, upon dorsiflexion, these two bones form a converging angle. The navicular, cuboid and metatarsals are also deformed and displaced and articulate improperly. The tendo Achilles is shortened.
Muscular atrophy is generalized and inherent.
The causes The causes of CTEV are unknown, but many factors may play a part. The child may have other anomalies such as spina bifida or arthrogryposis, in which case the clubfeet are considered teratologic deformities. Heredity is a factor, but the means of transmission are unknown. It seems linked to arrested skeletal development during the ninth to tenth week of embryonic life. Brockman believes that the primary deformity is caused chiefly by congenital atresia of the articulation of the head of the talus and that other changes are secondary to this abnormality.