Prosthetic management of a Chopart amputation variant

Abstract

The history and prosthetic difficulties of a patient with an unusual Chopart amputation variant have been presented. Although it is possible for the Chopart amputee to walk with just a shoe and filler, this patient does best with a formal prosthesis. The Chopart amputation, which has been surgically stabilized with Achilles tendon lengthening to prevent equinus contractures, can be fitted successfully with a lightweight circumferential plastic or silicone prosthesis or more traditionally with a solid ankle foot orthosis with filler. This partial foot prosthesis is worn with a sturdy shoe with a rocker and solid ankle cushion heel or a well constructed running shoe. The Chopart amputee with equinus contractures must be fitted with a Chopart clamshell prosthesis or solid ankle patellar tendon bearing orthosis with filler and the above shoe prescription. Recent variants of the partial foot prosthesis including the Imler partial foot prosthesis, the Lange silicone prosthesis, and the ankle corset prosthesis were described.

Ankle Dorsiflexion Arthrodesis to Salvage Chopart’s Amputation With Anterior Skin Insufficiency

“…The equinus and hindfoot varus deformity after Chopart's amputations can be successfully accommodated in the prosthesis, and numerous designs and adjustments have been recommended to prevent or treat complications of these malpositions. 2,6,9,12,15,22,24,25 However, if this conservative treatment fails, or if it is obviously not possible to achieve a closed wound in the acute setting, the surgical options with preservation of limb length are very limited. Free skin grafts will certainly fail, as will pedicled fasciocutaneous grafts if the hindfoot is not stabilized.…”

“…In this retrospective case series, 24 consecutive patients who had Chopart's amputations between April 1998 and September 2012 because of forefoot gangrene due to diabetic angiopathy and polyneuropathy (15 patients), severe soft tissue and bony trauma (6), and malignant tumor (3) were reviewed (Table 1). Either to allow for otherwise impossible primary tension free wound closure, to allow for successful free flap coverage, or to treat recurrent ulcerations not responding to conservative treatment and prosthetic adjustments, an ankle arthrodesis was performed in slightly more than neutral dorsiflexion in all of the patients.…”

The “Flap-Shaft” Prosthesis for Insensate Feet with Chopart or Lisfranc Amputations

“…Numerous prosthetic designs have been recommended to prevent complications of equinus and varus malposition after Chopart and Lisfranc amputations. 6 The need for proximal stability, i.e. a rigid shaft up to the knee, in mid-tarsal amputations has been recommended.…”

“…8,12,13,14,24 Patellar tendon-bearing prostheses, which tend to be heavy and cumbersome, are used to unload the short stump. 6,21,22…”

Soft tissue considerations in partial-foot amputations

“…This may be due in part to the frequent stump complications that have been reported, which include equinus, varus and anterior dislocation of the ankle. [71][72][73] One device that is currently in use is a two-part articulated prosthesis, which consists of a socket that is moulded to the remainder of the foot and a shoe insert into which the socket fits. In an attempt to reduce this tendency, the tibialis anterior may be transferred to the neck of the talus to reduce the plantarflexory moment of the advancement of the center of gravity over the support limb during the gait cycle.…”