Could it be Charcot Foot?
The Complaints and Investigation Committees have recently reviewed several complaints that involved a missed diagnosis of Charcot foot. Although the specific issues were different in each case reported to CPSM, the patients each presented with swelling of the foot in the context of diabetes. As Charcot Foot can be subtle in the early stages and must be identified early to avoid more severe outcomes, it is important to keep this condition in mind.
Charcot Foot is a neuro-arthropathy, usually resulting from trauma to a neuropathic foot, that leads to ligamentous and/or bony damage manifesting as fractures and disrupted morphology of the foot. One challenge is that the individual may not perceive or report the trauma due to the underlying lack of sensation. Damage occurs over time when the condition is not recognized.
What follows is a quick review of the condition:
- Charcot foot can present early as localized foot swelling, warmth, and erythema. Paresthesia, subluxation, fracture, or deformity can also be seen over time.
- It is often misdiagnosed as an infection.
- Foot ulcers raise concern, as osteomyelitis can coexist with Charcot arthropathy.
- Delay in diagnosing and treating Charcot foot can result in bone and joint degeneration, deformity, disability, or amputation.
- Peripheral neuropathy, with a lack of protective sensation is a significant contributing factor.
- Diabetes is the most common cause of Charcot foot in the western world.
- Other conditions include chronic alcoholism, leprosy, tabes dorsalis, poliomyelitis, or syringomyelia.
- Part of the foot assessment should include testing for the presence/absence of protective sensation using a 10-gram monofilament.
- Other joints are rarely involved, but ankles, knees, and spine may be affected, particularly in persons who have had spinal cord injuries.
- There are no specific definitive laboratory tests to confirm the diagnosis, but baseline plain radiographs and a follow-up in 2 weeks will help to determine whether there are changes in the structure of the foot. See table 1 below, used with permission from the authors (Embil et al).
- Caught in early stages, off-loading can prevent the complications or need for surgery
- If questions arise about this condition, please confer with a consultant knowledgeable with the condition.
Bottom line: This is not rare. The key to early diagnosis of Charcot arthropathy is a high index of clinical suspicion in a person with diabetes mellitus and peripheral neuropathy who presents with swelling, erythema, and increased warmth of the foot and ankle.
Table 1 | Diagnosis of Charcot arthropathy
History and physical examination
Source: Embil JM, Trepman E. A case of diabetic charcot arthropathy of the foot and ankle. Nat. Rev. Endocrinol 2009; 5: 577–581; doi:10.1038/nrendo.2009.174