Serial Casting for Reconstruction of a Deformed Charcot Foot: A Case Report

Introduction. Charcot neuroarthropathy may occur in patients with peripheral neuropathy who do not notice pain while their bones and joints collapse or breakdown under the constant pressure of body weight. This can lead to ulcerations from severe deformity and potentially life-threatening infections. Current treatments vary from immobilization to extensive reconstructive surgical interventions.   Methods. Serial casting, used to correct many pediatric deformities while bones are often more pliable, was used with a 63-year-old male patient who presented with an active phase of Charcot foot with ulceration. The patient previously underwent foot reconstruction and had all hardware removed prior to serial casting. Due to the potential pliability of the bones, serial casting was attempted to reform the shape and position of the foot in a reverse Ponseti-type serial casting to create a more stable structure with less deformity that could lead to epithelial breakdown. Results. The patient regained full ambulation with a plantigrade foot and no wounds, and was followed without complications for 36 months. Conclusion. Serial weekly casting was an effective modality for treatment of this patient’s Charcot foot deformity.

Charcot neuroarthropathy is a cyclical disease state that often causes severe and potentially limb-threatening deformity of the lower leg and foot.¹ Although commonly recognized with diabetic peripheral neuropathy, the Charcot foot can occur and has been seen with numerous other conditions that cause peripheral neuropathy, including chronic alcohol abuse.² With the continuously increasing size of the population of patients with diabetes, the number of people with deformities related to Charcot neuroarthropathy has grown.³ Pain is rarely experienced in the acute phase of Charcot neuroarthropathy. Hence, patients who experience acute occurrences continue to ambulate on feet which are unable to withstand the pressure of body weight, leading to further foot breakdown, deformities, and wounds.⁴

Immobilization, radiotherapy, and pharmacologic treatments have been used to conservatively manage the Charcot foot.⁵ Casting has been used prophylactically to prevent foot deformation. Moreover, shoegear and other pedal devices are often used to maintain adequate foot and leg position.⁶ Customized foot orthotics have been found to significantly reduce reulceration rates in feet deformed by Charcot neuroathropathy.⁶ Surgeries, including procedures with the application of external fixation devices, are sometimes necessary to stabilize or to realign joints.⁷ Treatment must be initiated early, prior to nonreversible bony changes setting in.⁵ 

Different classifications exist describing Charcot foot. Clinically, Charcot foot can be classified into the acute/active and chronic/inactive stages. The acute stage typically presents in the midfoot with a red, warm, and swollen foot.⁴ Due to neuropathy, pain is not always associated with the condition. No deformity is seen radiographically in the acute phase. In the chronic phase, foot erythema, edema, and temperature differences decrease and are replaced with foot deformation. Most common is the rocker bottom foot deformity with a prominent medial midfoot, which can become a high-risk region for ulceration.⁴

The Eichenholtz classification is based on the history of the disease progression, and is a radiographic classification with 3 stages: 1) development, 2) coalescence, and 3) consolidation. In the development stage, erythema, edema, and temperature increases occur in the foot. Radiographs have generally normal appearance with some fragmentation. In coalescence, local inflammation decreases but radiographic changes become more apparent. Fragment absorption and new bone formation with sclerosis are typically noted. In consolidation, local inflammation is eliminated and remodeling occurs. Radiographs may show the developed deformities, which grant increased risks for ulcerations.⁴

Serial casting is most often utilized in the pediatric population whose bones and soft tissue are more pliable and accepting of the gentle manipulations by sequential and consistent pressure. The Ponseti method, for example, is often utilized as treatment for congenital talipes equinovarus, often referred to as clubfoot.⁸ Furthermore, serial casting has been used in settings of idiopathic toe walking to avoid the need for invasive procedures.⁹ Serial casting has additionally been utilized in metatarsus adductus, the most common congenital foot deformity in newborns.¹⁰ In the adult population it is often used to manipulate soft tissue, especially contractures in a post cerebrovascular accident setting.¹¹ A general internet search as well as a PubMed search of “Plaster Casting, Charcot Foot, Correction,” alone and in combination, revealed no literature describing serial casting for osseous deformities in the adult population with Charcot neuroarthropathy. This article describes a case where serial positional casting was used to realign and reconfigure the shape and structure of a foot with deformation and ulceration due to Charcot neuroarthropathy.

A 63-year-old male presented to the authors’ clinic at the Shaarei Zedek Medical Center, Jerusalem, Israel with a red, hot, swollen foot and ankle, with a severe pronation deformity (Figure 1). On examination the patient was standing and ambulating on the medial aspect of his foot and had developed a University of Texas Diabetic Wound Classification 1A ulceration on the medial aspect of the foot over the navicular bone. In addition, there was small sterile blistering of the skin in multiple areas (Figure 2). The ankle, subtalar, and midfoot joints were found to have excessive movement attributed to the underlying joint destruction. A diagnosis of active development phase of Charcot foot was given.

Figure 1. 

Figure 2. 

The patient had undergone foot reconstruction surgery 6 months prior to presentation at another institution. Upon presentation, the patient was worried as to why there was no change in the shape of his foot. Most concerning to him was that he was not ambulating with a plantigrade attitude to the foot.

Upon further examination, it was determined that many of the sterile blisters were being caused by the implanted hardware backing out of their intended position (Figures 3 and 4). The patient was taken to the operating room, where all of his surgical hardware was removed. The patient was placed in a sterile dressing and invited back for follow-up to the clinic 3 days post-operation.

Figure 3.

Figure 4.

At the first clinic visit, the wounds were progressing nicely. It was noted that there was excessive motion at the joints of the rearfoot and midfoot and the patient described that “there was a feeling of jelly instead of solid bone.” It was decided that due to the aggressive nature of the Charcot neuroarthropathy and potential pliability of the bones, serial casting to reform the shape and position of the foot would be used. It was decided to attempt reversing the order used in a standard Ponseti-type serial casting and to first mobilize the rearfoot so that a plantigrade foot strike could be achieved. Weekly casts were placed, with progressive supination obtained until the foot was almost neutral. Prior to casting, subtalar joint range of motion was evaluated to determine how much supination could be applied to the foot. In general, approximately one-fourth of the remaining available supination was casted from the resting subtalar position. At the same time, the midfoot joints were manipulated to provide a neutral forefoot strike and much of the longitudinal arch was preserved. The midfoot and longitudinal arch was done on a more supportive basis; the cast was pressed into a molded position and then further pressured until there was a solid connection with the plantar surface of the foot.

After 4 months of casting the patient was able to utilize a straight last, lace-up boot. The patient was followed for 36 months after the procedure and had full ambulation with a plantigrade foot and generally stable epithelium without consequence of new wounds while wearing only his customized boots (Figure 5). Figure 6 shows a current x-ray taken just before publication of this report, and Figure 7 shows the patient standing.  

Figure 5.

Figure 6.

Serial casting uses the relative pliability of soft tissue to its advantage. To that end, it is used in pediatrics both for correction of soft tissue deformities as well as for some osseous conditions where patients still have softer bone due to their young age. In adults, serial casting is almost exclusively used in soft tissue contractions such as in patients recovering from a stroke. In this case, the thought process of the treating physicians was that in the acute development phase of Charcot foot, the bone has a relative softness comparable to a pediatric patient. It was this property, as well as the relative mobility and motility of the Charcot joints, that the authors sought to manipulate. With gentle counterpressure, the authors were able to achieve manipulation and maneuver the foot into an acceptable position.

This procedure is appropriate for patients in the acute phase of Charcot destruction. It is not appropriate on patients who have atrophic or friable skin where there is the risk of ulceration from the pressure of the casting.

For the patient described in this paper, serial weekly casting was an effective modality for treatment of his Charcot foot deformity and concomitant wounds. The patient is still being followed with positive results. He has had 2 more episodes of Charcot neuroarthropathy and was placed in a circular cast for 2 weeks; both times with no destruction.

Since this case, the authors have treated 7 other patients with serial casting for deformities caused by Charcot neuroarthropathy. Satisfactory results are being recorded with follow-up periods ranging from 3-28 months.

Address correspondence to:

Jonathan I. Rosenblum
Shaarei Zedek Medical Center
diabfootman@gmail.com

Disclosure: The authors disclose no financial or other conflicts of interest.