Congenital Vertical Talus

Congenital Vertical Talus (CVT), also known as "rocker-bottom foot," is a rare rigid flatfoot deformity characterized by fixed dorsal dislocation of the navicular on the talus, resulting in a rigid and irreducible hindfoot valgus and forefoot dorsiflexion.

Key Characteristics:

• Fixed dorsal navicular dislocation
• Rigid equinus of the hindfoot
• Forefoot dorsiflexion and abduction
• Convex plantar surface
• Rigidity of deformity

Epidemiology

• Incidence: 1 in 10,000 live births
• Bilateral in 50% of cases
• Male:Female ratio = 1:1
• Associated conditions in 50-90% of cases
• Strong genetic component

Pathoanatomy

• Key Deformities:
  • Vertically oriented talus
  • Dorsal dislocation of navicular
  • Contracture of anterior tibialis
  • Contracted dorsal capsule
  • Posterior tibialis dysfunction
• Anatomical Changes:
  • Hindfoot equinus
  • Talonavicular dissociation
  • Forefoot dorsiflexion
  • Altered muscle balance

Clinical Presentation

• Physical Findings:
  • Rigid rocker-bottom deformity
  • Prominent talar head plantarly
  • Deep crease on dorsum of foot
  • Fixed hindfoot equinus
  • Inability to reduce deformity
• Key Signs:
  • Rigid deformity from birth
  • Convex plantar arch
  • Dorsal bunion appearance
  • Tight anterior tendons
  • Poor passive motion

Diagnostic Imaging

• Radiographic Features:
  • Lateral view:
    • Vertical orientation of talus
    • Dorsal displacement of navicular
    • Parallel axes of talus and 1st metatarsal
  • AP view:
    • Forefoot abduction
    • Talar head uncoverage
    • Hindfoot valgus
• Advanced Imaging:
  • MRI: For complex cases
  • CT: Surgical planning
  • Stress radiographs

Associated Syndromes and Conditions

• Neuromuscular Disorders:
  • Arthrogryposis
  • Myelomeningocele
  • Sacral agenesis
  • Spinal muscular atrophy
• Chromosomal Abnormalities:
  • Trisomy 13, 15, 18
  • De Lange syndrome
  • Down syndrome
• Other Associations:
  • HOXD10 gene mutations
  • DiGeorge syndrome
  • Prune belly syndrome
  • Neurofibromatosis

Systemic Evaluation

• Required Assessments:
  • Neurological examination
  • Genetic consultation
  • Spine evaluation
  • Hip screening
  • Cardiac assessment

Treatment Approach

• Initial Management:
  • Early intervention crucial
  • Serial manipulation and casting
  • Dobbs method preferred
  • Weekly cast changes
• Dobbs Method:
  • Reverse Ponseti technique:
    • Sequential hindfoot and forefoot correction
    • Pin fixation of talonavicular joint
    • Percutaneous Achilles tenotomy

Surgical Management

• Limited Surgery:
  • Percutaneous talonavicular pinning
  • Achilles tenotomy
  • Anterior tibial tendon transfer
• Extensive Surgery:
  • Single-stage correction:
    • Extensive soft tissue release
    • Talonavicular reduction
    • Pin fixation
    • Tendon balancing

Post-Treatment Care

• Bracing Protocol:
  • Full-time bracing initially
  • Gradual weaning
  • Night bracing until age 4-5
• Monitoring:
  • Regular radiographic assessment
  • Growth monitoring
  • Functional evaluation
  • Long-term follow-up

Complications and Outcomes

• Potential Complications:
  • Recurrence (10-50%)
  • Overcorrection
  • Stiffness
  • Avascular necrosis
  • Wound problems
• Long-term Outcomes:
  • Better with early treatment
  • Variable with associated conditions
  • Regular monitoring needed
  • Possible arthritis in adulthood