Congenital vertical talus is a rigid
deformity due to dorsal dislocation of the navicular on the head
of the talus. Best viewed on lateral radiographs. In children whose
navicular is yet to ossify (< 3-4 years), differentiation from
a flexible flat foot is made by passive plantarflexion of the forefoot
on the rearfoot. If the talar declination remains the same it is
a congenital vertical talus. Major findings are oblique talus and
negative calcaneal inclination angle due to the severe equinus deformity.
The radiographic appearance of a
vertical talus is quite characteristic, even in the neonate. Often
the calcaneus is in an equines position and has become narrowed
and beak shaped anteriorly. Upon weightbearing a characteristic
'hour glass' appearance of the talus develops. The talar neck is
often seen to elongate. The forefoot is characteristically dorsiflexed
and abducted at the midtarsal joint. On the dorsoplantar view, the
talocalcaneal angle is characteristically greater than 40 degrees.
Unfortunately we were unable to find
a radiograph of this condition. As this site is updated hopefully
this will change!
