What is Charcot foot (Charcot neuroarthropathy)?

From the Guidelines

Charcot foot is a serious complication of diabetes that requires immediate non-weight bearing and offloading to prevent further joint destruction and deformity, and the initial treatment should involve knee-high immobilization/offloading, as recommended by the guidelines on the diagnosis and treatment of active Charcot neuro-osteoarthropathy in persons with diabetes mellitus (IWGDF 2023) 1. The diagnosis of Charcot foot is based on clinical findings of increased temperature, edema, and/or redness of the foot, compared to the contralateral foot, and should be considered in persons with diabetes mellitus and neuropathy 1. Some key points to consider in the diagnosis and treatment of Charcot foot include:

• Using infrared thermometry to measure skin temperature of the feet in a person with diabetes mellitus and suspected Charcot neuro-osteoarthropathy with intact skin, using a standardized approach to the measurement of temperatures to allow for more accurate comparison over time 1
• Initiating knee-high immobilization/offloading promptly while further diagnostic studies are performed to confirm or rule out active Charcot neuro-osteoarthropathy (CNO) when active CNO is suspected in a person with diabetes mellitus and intact skin 1
• Performing plain X-ray of the foot and ankle in a person with diabetes mellitus and suspected active Charcot neuro-osteoarthropathy, ideally with bilateral plain X-rays for comparison purposes 1
• Considering Magnetic Resonance Imaging (MRI) in a person with diabetes mellitus and suspected active Charcot neuro-osteoarthropathy with normal appearance of the plain X-rays to diagnose or exclude the disease and its activity 1 The treatment of Charcot foot should focus on offloading and immobilization, and may involve the use of a total contact cast or removable boot, as well as custom orthotic footwear to prevent recurrence and ulceration 1. Some key points to consider in the treatment of Charcot foot include:
• Using a non-removable knee-high device to immobilize and offload the foot to promote the remission of the disease, and prevention or progression of deformity in a person with active Charcot neuro-osteoarthropathy and intact skin 1
• Considering a total contact cast in the treatment of active Charcot neuro-osteoarthropathy with intact skin in a person with diabetes mellitus, with a knee-high walker rendered non-removable as a second choice 1
• Avoiding the use of below the ankle offloading devices, such as surgical shoes or custom molded shoes, due to inadequate immobilization of the diseased bone and joints, and limited off-loading capacity 1 Overall, the management of Charcot foot requires a comprehensive approach that includes prompt diagnosis, offloading and immobilization, and prevention of recurrence and ulceration, as well as consideration of the individual patient's needs and circumstances 1.

From the Research

Definition and Pathophysiology of Charcot Foot

• Charcot foot, also known as Charcot neuroosteoarthropathy (CN), is a rare complication of diabetic neuropathy 2.
• The pathogenesis of Charcot foot involves repetitive micro-trauma in a foot with impaired sensation and neurovascular changes caused by pathological innervation of the blood vessels 3.
• The development of Charcot foot requires the coincidence of neuropathy and inflammation, with neuropathy being essential for its development 4.

Diagnosis and Classification of Charcot Foot

• The diagnosis of Charcot foot is often delayed in diabetic patients, which can lead to harmful consequences including amputation 3.
• A high index of suspicion is required from both the diabetic patient and their physicians for early diagnosis and treatment to prevent major complications 2.
• Clinical diagnostic pathways based on different classifications are presented, and multidisciplinary assessment between diabetologists and radiologists is fundamental for prompt diagnosis 3, 2.

Treatment and Management of Charcot Foot

• Offloading of the foot to stop the perpetuation of trauma and inflammation is the cornerstone of medical therapy of Charcot foot 2.
• Casting therapy has been accepted as the mainstay treatment of the acute Charcot foot, although there are still controversies regarding its duration and type of cast 5.
• Antiresorptive therapies, such as bisphosphonates and calcitonin, have been evaluated in the treatment of Charcot foot, but current evidence to support their use is weak 5.
• Orthotic management, including total contact cast, Charcot restraint orthotic walker, and prefabricated diabetic walker, can be used for the treatment of Charcot feet after external fixation surgery 6.