Chopart Amputation

Chopart amputation is a disarticulation at the talonavicular and calcaneocuboid level.

Benefits of Chopart Amputation are higher level of ambulation because of preserving limb length compared to trans-tibial amputation and walking short distances without prosthesis because direct loading of the residual limb is possible.

See Also: Ankle Anatomy

Chopart Amputation Procedure Steps

• To prevent contamination, start by making an incision on the back and inner side of the foot, followed by cutting the Achilles tendon. Remove a 2 cm section of the tendon while trying to preserve the Achilles tendon sheath. Handle the soft tissue delicately.
• Prior to the operation, mark the incision site on the skin, creating a “fishmouth” shape on the sole of the foot. Begin the incision at the inner and outer transtarsal joints. Extend the flaps in both upward and downward directions to ensure sufficient skin coverage. Continue the incision through the skin and subcutaneous tissue.
• Carefully locate and pull the superficial sensory nerves towards the toes, then cut them and let them retract.
• Identify the front tendons of the tibia and the extensor hallucis longus, cut them at a distance from their attachment points, and prepare them for transfer.
• Identify the transverse tarsal joints (calcaneocuboid and talonavicular) and separate them by releasing the ligaments on the top and bottom.
• Transfer the front tibial tendon to the lateral side of the talus neck. This can be done using a bone tunnel and securing it with a biotenodesis screw, or by creating a groove in the talus and using a suture anchor or staple for fixation. Some experts suggest that a single tendon transfer may not be sufficient to balance the foot in this situation. In addition to transferring the front tibial tendon to the talus neck, it is also possible to transfer the peroneus brevis or extensor hallucis longus to the front process of the calcaneus. Additionally, the front tibial and extensor hallucis longus tendons can be tenodesed and transferred to the talus neck, and the extensor digitorum longus tendon can be transferred to the front aspect of the calcaneus.
• Close the wound by aligning the layers of connective tissue on the sole and top of the foot, and then stitch the skin without tension. If necessary, insert a drainage tube after achieving hemostasis and thoroughly irrigating the wound.
• Finally, apply a well-cushioned rigid dressing that maintains dorsiflexion.

Aftercare

• The dorsiflexion rigid dressing is changed intermittently to check the wound. Sutures are kept in place for 4 to 6 weeks to allow for adequate healing.
• The splint must be worn for 6 to 8 weeks to prevent equinus contracture of the hindfoot.
• The patient will need an ankle-foot orthosis in a rocker-sole shoe (e.g., running shoe) for ambulation

A modified Chopart’s amputation has been designed to overcome the complications of the traditional Chopart’s amputation of plantar flexion and skin breakdown over the anterior talus and calcaneus. The modifications are:

1. Contouring of the talus and calcaneus;
2. Transfer of the anterior and posterior tibialis tendons and the extensor communis and hallucis to the neck of the talus and sustentaculum tali;
3. Anterior advancement of the plantar flap;
4. Lengthening of the tendo Achillis. 

A systematic review study founds that the need for re-amputation because of wound healing problems seems to occur quite often, especially after conventional Chopart amputation. When considering a Chopart amputation, the modified Chopart shows a trend towards the best outcome concerning wound healing and re-amputation rate compared to a conventional Chopart amputation. However, although the total number of patients is low, Lisfranc amputation does seem to favor both types of Chopart amputation. Lisfranc and both Chopart amputations provide patients with a functional residual limb, with the remaining ability to ambulate without prosthesis for short distances.

References & More

• van der Wal GE, Dijkstra PU, Geertzen JHB. Lisfranc and Chopart amputation: A systematic review. Medicine (Baltimore). 2023 Mar 10;102(10):e33188. doi: 10.1097/MD.0000000000033188. PMID: 36897730; PMCID: PMC9997832. Pubmed
• Letts M, Pyper A. The modified Chopart’s amputation. Clin Orthop Relat Res. 1990 Jul;(256):44-9. PMID: 2364621. Pubmed
• Campbel’s Operative Orthopaedics 12th edition Book.