Systemic Disease and Podiatric Medicine
Core concepts
Understand how systemic disease manifests in the foot: diabetes (neuropathy, vasculopathy, infection), gout (podagra, tophi), rheumatoid arthritis (symmetric small joint involvement, erosions), peripheral arterial disease (claudication, rest pain, tissue loss), and connective tissue disorders. Know the podiatric implications of each-when to refer, what to monitor, and how to modify care. Familiarize yourself with the diabetic foot examination and risk stratification, and the role of glycemic control, blood pressure, and lipid management in preventing complications.
Traps in questions
A frequent trap is attributing a foot finding to a local cause when a systemic disease is responsible-for example, missing gout in a red, hot first MTP joint or missing rheumatoid arthritis in symmetric forefoot pain. Another is failing to recognize that neuropathy in a diabetic patient is a risk factor for ulceration even without symptoms. Know that a normal pulse examination does not exclude peripheral arterial disease in a diabetic patient with calcified vessels.
Rule of thumb
When a foot finding is bilateral, symmetric, or involves multiple joints, think systemic disease first.
Worked example
A patient with a red, hot, swollen first MTP joint and a history of alcohol use likely has gout. Aspiration showing negatively birefringent needle-shaped crystals confirms the diagnosis.