A Guide To Bracing For Charcot
Charcot neuroarthropathy is a progressive deterioration of a joint characterized by a loss of sensation. When left untreated, this condition can lead to pathological fractures, joint dislocation/subluxation and deformity. This condition reportedly affects an estimated 0.8 percent to 7.5 percent of people with diabetes. The prevalence of this condition increases dramatically among patients with diabetes and peripheral neuropathy, ranging from 29 to 35 percent in this specific population.1,2 However, this disorder is not limited to patients with diabetes as it can also afflict patients with other neurological disorders such as syringomyelia, congenital insensitivity to pain, leprosy, syphilis, myelomeningocele and alcoholic neuropathy. The exact pathogenesis of this condition is unknown, but there are two leading theories. The neurotraumatic theory hypothesizes that the neuropathic foot is subjected to repetitive microtrauma, which leads to progressive destruction and deformity. The neurovascular theory hypothesizes that autonomic dysfunction leads to arteriovenous shunting and demineralization of bone. However, Charcot is more likely to result from a combination of the two. Early diagnosis and initiation of treatment is crucial for the patient with acute Charcot. The goal of treatment is maintaining a stable foot (i.e., one that has no tendency to subluxate or dislocate without support) and ensuring that it fits in a shoe or brace without a tendency to recurrent ulceration and infection.3 In the acute setting, nonweightbearing of the affected extremity is recommended until there is resolution of edema and radiographic evidence of coalescence. However, there is a difference in opinion on the best way to accomplish this. While nonweightbearing is the gold standard of treatment for acute Charcot, one must consider many variables before initiating treatment for those with chronic Charcot. These factors include the degree of deformity, abnormal foot and ankle mechanics, patient compliance and satisfaction, and the presence of concurrent ulceration. Custom footwear and bracing devices are important considerations for patients with Charcot but one must choose from a wide variety of bracing devices and footwear that are currently available. Ideally, these devices should help protect the extremity from repetitive microtrauma, prevent skin breakdown or recurrence of the disease process, supplement wound healing of any ulcerations and assist the patient during ambulation. The choice of the device or shoe will change according to the stage of disease. Additionally, one must decide when it is appropriate to treat with over-the-counter (OTC) prefabricated devices/shoes versus custom-made devices. For the purposes of this article, we will assume the majority of patients have some degree of osseous deformity present. When this is the case, choosing an appropriate device is dependent upon the degree of deformity and its location. If you recognize the disease process early and promptly initiate treatment, the hope is that only minimal changes have occurred to the architecture of the foot and ankle. However, you often may see a patient present with an advanced stage of the disease and significant deformity. One may have to sacrifice functional stability of an orthosis in order to accommodate for this deformity. What The Literature Reveals About Total Contact Casting Total contact casting (TCC) is currently the mainstay of treatment for acute Charcot. Pinzur, et. al., found that TCC was the initial treatment for 49 percent of patients treated for acute Charcot.4 The effectiveness of this cast lies in its ability to reduce plantar pressures, which is accomplished by spreading the weightbearing forces over an increased surface area of the leg and foot.5 Lavery, et. al., found TCC to be the most effective modality for reducing forefoot pressures, citing up to an 84 percent decrease.6 A separate investigation demonstrated the average forefoot pressure in a TCC was 4.47 N/cm2 compared to 12.96 N/cm2 in a running shoe.7 Another advantage of using the TCC is the ability to almost ensure patient compliance. On the downside, the TCC requires a skilled technician and a relatively long application time with numerous applications needed over the duration of healing. The TCC also tends to be unpopular with patients.