Fetal Club Foot

Talipes equinovarus is a fixed deformity with four components:

  • Equinus (plantar flexion at ankle)
  • Varus (hindfoot inversion)
  • Adductus (forefoot medial deviation)
  • Cavus (high medial arch)

Unilateral clubfoot

  • More likely isolated
  • Lower genetic yield
  • Better prognosis
  • Think positional or idiopathic first

Bilateral clubfoot

  • Higher chance of underlying pathology
  • Stronger association with:
    • Aneuploidy
    • Neuromuscular disease
    • Syndromic conditions

True clubfoot vs positional

True clubfoot

  • Foot stays inverted on repeated scans
  • Tibia–foot angle abnormal
  • Sole of foot seen in same plane as tibia
  • Associated calf muscle hypoplasia postnatally

Positional foot

  • Changes position during scan
  • Normal ankle motion
  • Often resolves later in pregnancy

Isolated clubfoot

Isolated clubfoot (most common)

  • No other structural anomalies
  • Normal growth
  • Normal CNS and spine
  • Normal fetal movements

Prognosis excellent

Non-isolated clubfoot (red flags)

  • Spine: tethered cord, spina bifida
  • Brain: ventriculomegaly, ACC
  • Limbs: arthrogryposis, clenched hands
  • Thorax: small chest
  • Growth restriction
  • Reduced fetal movements

Aneuploidy

More common with bilateral + other anomalies

  • Trisomy 18 (classic)
  • Trisomy 13
  • Trisomy 21 (less common, usually with other markers)

Copy number variants

  • 22q11.2 deletion
  • Submicroscopic CNVs when clubfoot is part of a pattern

Single-gene disorders

Neuromuscular

  • Spinal muscular atrophy
  • Congenital myopathies
  • Myotonic dystrophy

Clues:

  • Reduced movements
  • Polyhydramnios
  • Arthrogryposis

Syndromic / connective tissue

  • Distal arthrogryposis
  • Larsen syndrome
  • Multiple pterygium syndromes

Idiopathic / multifactorial

  • Majority of isolated cases
  • Polygenic + environmental factors
  • Strong male predominance

Prognosis

Isolated clubfoot

  • 90–95% walk normally
  • Ponseti casting ± minor surgery
  • Normal intelligence
  • Normal quality of life

Unilateral often slightly easier to treat than bilateral.

Bilateral isolated clubfoot

  • Still excellent outcomes
  • Longer casting
  • Slightly higher relapse rate
  • Good long-term function
  • Clubfoot must be fixed, not positional
  • Bilateral = higher genetic yield
  • Isolated clubfoot is a treatable orthopedic condition, not a neurodevelopmental diagnosis

Red flags

  • Reduced fetal movements
  • Arthrogryposis / joint contractures
  • Limb shortening or multiple limb anomalies
  • CNS abnormalities (VM, ACC, posterior fossa)
  • Spinal anomalies
  • Cardiac defects
  • Growth restriction / polyhydramnios

ISOLATED CLUBFOOT

  • No red flags above
  • Normal movements
  • Normal CNS, spine, heart
  • Normal growth

Genetics yield

Test Expected diagnostic yield
Karyotype <1%
CMA 1–3%
Exome <2%

NON-ISOLATED / SYNDROMIC CLUBFOOT

RED FLAGS

  • Neuromuscular (↓ movements)
  • Skeletal dysplasia (patterned limb findings)
  • Chromosomal / syndromic

Genetics yield

Test Expected diagnostic yield
Karyotype 5–10%
CMA 10–20%
Exome 20–40% (highest with arthrogryposis)

Genetics

  • Offer CMA to all
  • Consider exome if:
    • Arthrogryposis
    • Multiple anomalies
    • Progressive contractures

Prognosis

  • Determined by underlying diagnosis
  • Foot correction may be incomplete

Counseling sentence

"The foot finding may be part of a broader condition, which determines prognosis more than the foot itself."