Clubfoot

Clubfoot, or congenital talipes equinovarus, is a complex congenital deformity involving the foot and ankle.

The deformity consists of four linked components remembered as CAVE:

• Cavus: plantar flexion of the first ray producing a high medial arch
• Adductus: medial deviation of the forefoot
• Varus: inversion of the hindfoot
• Equinus: plantar flexion at the ankle

The deformity is three dimensional. It is not simply an ankle equinus deformity.

Clubfoot may be:

• Idiopathic
• Syndromic, including arthrogryposis and myelomeningocele
• Neuromuscular
• Complex or atypical

Idiopathic clubfoot is usually isolated and responds very well to the Ponseti method. Syndromic and atypical feet are more rigid, relapse more frequently and may require modified treatment.

The treatment objective is a painless, plantigrade, flexible foot that functions normally without extensive surgical scarring.

The foot is characteristically:

• Plantar flexed
• Inverted
• Adducted
• Smaller than the opposite foot in unilateral disease

The affected calf is often smaller because of reduced muscle bulk.

The heel appears small and is drawn upward by the tight Achilles tendon.

Deep medial and posterior skin creases suggest greater rigidity.

Assess whether the deformity is passively correctable.

Examine the entire child for associated conditions, particularly:

• Spinal dysraphism
• Arthrogryposis
• Developmental dysplasia of the hip
• Neuromuscular abnormalities
• Other congenital limb deformities

An isolated flexible positional foot that corrects completely with gentle manipulation is not true structural clubfoot.

Diagnosis is clinical.

Routine radiographs are unnecessary for a typical newborn with idiopathic clubfoot.

Prenatal ultrasound can identify the deformity before birth but cannot reliably determine final severity or response to treatment.

Clinical assessment should document:

• Hindfoot equinus
• Heel varus
• Forefoot adduction
• Cavus
• Rigidity
• Associated abnormalities

The Pirani score can be used to document severity and response serially, but treatment should be based on the actual correction rather than the score alone.

Ponseti treatment

Begin treatment during the first weeks of life whenever feasible, although older infants can still respond.

The Ponseti method is the standard initial treatment for idiopathic clubfoot and achieves initial correction in approximately 95% of cases.

Manipulate and cast in the correct sequence.

1. Correct cavus first

The cavus results largely from plantar flexion of the first ray.

Elevate the first metatarsal while maintaining the natural supination of the forefoot.

Do not pronate the forefoot because this worsens cavus and locks the calcaneus beneath the talus.

2. Correct adduction and heel varus together

Stabilise the talar head and abduct the entire foot around the talus.

The calcaneus should rotate laterally beneath the talus as forefoot abduction progresses.

Do not forcibly evert the heel independently.

Serial long leg casts are applied approximately weekly.

Most typical feet correct after roughly 4 to 7 casts.

3. Correct equinus last

Do not attempt dorsiflexion until cavus, adduction and heel varus are corrected.

Persistent equinus is usually caused by a tight Achilles tendon.

Most infants require percutaneous Achilles tenotomy.

After tenotomy, apply the final cast with the ankle dorsiflexed and the foot appropriately abducted.

Maintain this cast for approximately 3 weeks to allow Achilles tendon healing.

Foot abduction brace

Correction is only the first phase. Prevention of recurrence is essential.

After the final cast, use a foot abduction brace.

A common regimen is:

• Approximately 23 hours per day for the first 3 months
• Thereafter during sleep and naps, approximately 12 to 14 hours daily
• Continue until approximately 4 years of age

The affected foot is generally held around 60° to 70° external rotation. The normal foot in unilateral disease is held at a smaller angle.

Poor brace adherence is one of the strongest predictors of relapse.

Relapse

Early relapse may present with:

• Reduced ankle dorsiflexion
• Recurrent heel varus
• Forefoot adduction
• Dynamic supination during walking

Restart Ponseti manipulation and casting rather than proceeding immediately to extensive surgery.

Recurrent equinus may require repeat Achilles tenotomy.

Dynamic supination

A child who has a corrected passive foot but dynamically supinates during swing phase may have relative overactivity of tibialis anterior.

After sufficient ossification, usually after approximately age 2.5 to 3 years, recurrent dynamic supination can be treated with tibialis anterior tendon transfer to the lateral or central dorsum of the foot.

The procedure should only be performed after the passive deformity has first been corrected with casting.

Resistant clubfoot

Extensive posteromedial release is now reserved for feet that cannot be corrected using meticulous Ponseti based treatment.

Large early soft tissue releases can create:

• Severe stiffness
• Scar tissue
• Weakness
• Painful arthritic feet in adulthood

The goal should remain correction with the least destructive treatment possible.