Ponseti Casting - Concept and Technique

What is the Ponseti Method?

The Ponseti method is a systematic, non-surgical approach to correcting congenital clubfoot (talipes equinovarus) using serial manipulation and casting. Developed by Dr. Ignacio Ponseti at the University of Iowa, it has become the global standard of care, achieving correction in over 90-95% of idiopathic cases without the need for formal surgical release.

Campbell's Operative Orthopaedics, 15th Ed.
Bailey and Love's Short Practice of Surgery, 28th Ed.

The Deformity Being Corrected (CAVE)

Clubfoot has four components corrected in a specific order, remembered by the mnemonic CAVE:

Component	Deformity	Correction Order
C - Cavus	High arch / plantar flexion of 1st ray	1st
A - Adductus	Forefoot adduction	2nd
V - Varus	Hindfoot varus	3rd
E - Equinus	Plantarflexion of the hindfoot	Last

The equinus is always corrected last, because attempting to dorsiflex the foot before correcting the varus creates a rocker-bottom deformity.

The Key Anatomical Principle

The head of the talus acts as the fulcrum around which all correction occurs. The navicular, calcaneus, and forefoot are rotated around the talar head. Crucially, the calcaneus is NOT directly manipulated to correct varus - instead, abducting the forefoot against the fixed talar head simultaneously unlocks and corrects the hindfoot varus.

Two Phases of Treatment

Phase 1 - Treatment Phase (Casting)

Timing: Begins ideally within the first 2-4 weeks of life. Older children can also be treated.

Frequency: Weekly cast changes (an accelerated biweekly schedule is an accepted modification).

Cast type: Above-knee (toe-to-groin) long leg plaster cast with the knee at ~90° flexion. This prevents cast slippage and controls rotation.

Step-by-step technique (Campbell's, Technique 31.10):

First Cast - Correct Cavus
- Supinate (dorsiflex) the first metatarsal to bring the forefoot in line with the hindfoot.
- This removes the apparent cavus by aligning the forefoot with the heel.
- Applied as a short leg cast first, then extended above the knee once set.
Subsequent Casts - Correct Adductus and Varus simultaneously
- Thumb is placed over the lateral aspect of the talar head (the fulcrum).
- The forefoot is abducted (externally rotated) against the stabilized talar head.
- The varus of the hindfoot self-corrects as the calcaneus rotates under the talus.
- Forefoot is gradually abducted to 60-70° of external rotation over successive casts.
- Never apply direct pressure to the heel or the calcaneus - this causes iatrogenic rocker-bottom.
Final Cast - Correct Equinus
- Once 60-70° of forefoot abduction is achieved, dorsiflexion is gently applied.
- ~80% of feet need a percutaneous Achilles tenotomy first (due to tight tendo Achillis preventing dorsiflexion beyond neutral).
- The tenotomy is a minor outpatient procedure under local anaesthesia.
- After tenotomy, a final cast is applied for 3 weeks to allow tendon healing.

Total number of casts: Typically 5-8 casts over 5-8 weeks.

Here is what the serial casts look like - progressing from uncorrected (right) to corrected (left):

Serial casts documenting stepwise Ponseti correction

Phase 2 - Maintenance Phase (Bracing)

After the final cast is removed, the corrected position must be maintained with a Foot Abduction Orthosis (FAO) - also called a Denis-Browne bar:

Full-time (23 hrs/day) for the first 3 months
Night and nap time for the next 4-5 years

The affected foot is held in ~70° external rotation and slight dorsiflexion; in bilateral cases, both feet are abducted. Non-compliance with the FAO is the single most important cause of relapse.

Scoring / Classification Systems Used

Pirani Score (0-6 scale): Grades severity using 6 signs - curved lateral border, medial crease, lateral head of talus palpability (midfoot) + posterior crease, rigid equinus, empty heel (hindfoot). Used to track correction progress with each cast.
Dimeglio Classification: Grades based on 4 parameters (derotation, adduction, varus, equinus) on a 0-4 scale each (total 0-20).

Outcomes and Recurrence

Parameter	Data
Success rate (idiopathic)	>90-95%
Achilles tenotomy required	~80% of cases
Recurrence rate	10-30%
Most important recurrence factor	Non-compliance with FAO brace
Recurrence management	Repeat casting +/- tenotomy; TATT at 2.5-4 years if dynamic supination persists

Feet treated with Ponseti casting are less stiff, less painful, and less subject to overcorrection than surgically treated feet. - Bailey and Love, 28th Ed.

When Ponseti Fails

If conservative treatment fails, surgical intervention (posterolateral soft tissue release) is performed ideally before walking age, using Turco or Cincinnati incisions for sequential release of pathologically tight structures. Surgery is more often required in non-idiopathic clubfoot (e.g., arthrogryposis, myelomeningocele-associated).

Summary Mnemonics

Order of correction: CAVE (Cavus → Adductus → Varus → Equinus)

Key principles:

Talar head = fulcrum
Never compress the heel directly
Abduct forefoot to 60-70° before treating equinus
Compliance with FAO is everything

This is a shared conversation. Sign in to Orris to start your own chat.