Congenital Vertical Talus

Description

Congenital vertical talus is a rare congenital foot deformity characterized by dorsal dislocation of the talonavicular joint, resulting in a rigid vertical position of the talus. The calcaneus is positioned beneath the talus, giving the foot a characteristic “rocker-bottom” appearance. The condition occurs in approximately 1 in 10,000 live births. It is bilateral in about 50% of cases and is frequently associated with sacral agenesis, arthrogryposis, and chromosomal abnormalities such as trisomy syndromes. The underlying cause is thought to involve abnormal embryonic development or neuromuscular imbalance.

Congenital vertical talus is classified into three types:

a) teratologic – typically bilateral and associated with severe, rigid deformity;

b) neuromuscular – resulting from muscle imbalance caused by neurological disorders;

c) acquired.

Symptoms

The hindfoot is in equinus, while the forefoot is dorsiflexed and abducted. The longitudinal arch is convex, producing the characteristic rocker-bottom foot deformity. The deformity is rigid and cannot be corrected with passive manipulation.

Diagnosis

The diagnosis is based on clinical examination and radiographic findings. Lateral radiographs demonstrate a vertically oriented talus, an increased talocalcaneal angle, and dorsal dislocation of the talonavicular joint, with the navicular resting on the neck of the talus.

Treatment

Conservative treatment alone is generally ineffective. It is mainly used before surgery to improve foot alignment and stretch the soft tissues. Surgical treatment consists of reduction of the dislocated joints and lengthening of contracted tendons. Equinus deformity is corrected by Achilles tendon lengthening.

The prognosis depends on the severity of the underlying disorder and the age at treatment, with the best outcomes achieved in children operated on before 6 months of age. If recurrence occurs, additional procedures such as osteotomy or arthrodesis may be required.

Source | Author Doctor Nikas Samuolis, reviewed by Prof. Virginijus Šapoka | Vilnius University | Faculty of Medicine | Head of the Department of Internal Medicine, Family Medicine, and Oncology