A 48-year-old overweight man comes to the physician for evaluation of a right foot ulcer that he first noticed 3 weeks ago. He has a history of hypertension, type 2 diabetes mellitus, and hypercholesterolemia. His current medications include ramipril, aspirin, metformin, sitagliptin, and rosuvastatin. He has a 20-pack-year smoking history and occasionally drinks alcohol but does not use illicit drugs. The patient is afebrile. His blood pressure is 132/80 mm Hg and pulse is 76/min. Examination shows a 1.7 x 2 cm ulcer on the plantar surface of the great toe. Which of the following tests will best assess this patient's risk of foot ulcers?

Question

A 48-year-old overweight man comes to the physician for evaluation of a right foot ulcer that he first noticed 3 weeks ago.  He has a history of hypertension, type 2 diabetes mellitus, and hypercholesterolemia.  His current medications include ramipril, aspirin, metformin, sitagliptin, and rosuvastatin.  He has a 20-pack-year smoking history and occasionally drinks alcohol but does not use illicit drugs.  The patient is afebrile.  His blood pressure is 132/80 mm Hg and pulse is 76/min.  Examination shows a 1.7 x 2 cm ulcer on the plantar surface of the great toe.  Which of the following tests will best assess this patient's risk of foot ulcers?

Quizplus · Accepted Answer

11ec25c8_d12c_96e8_bc81_51e8b2009ba3_MD0003_00 This patient has a diabetic foot ulcer, which can eventually lead to nontraumatic lower limb amputation. Risk factors for diabetic foot ulcers include diabetic neuropathy, previous foot ulceration, vascular disease, and foot deformity. Diabetic neuropathy is the most common underlying cause and is found in >80% of patients with diabetic foot ulcers. Neuropathy decreases pain sensation and pressure perception, it causes muscle imbalance leading to foot deformities, and impairs the microcirculation and integrity of the skin. Neuropathic ulcers most commonly occur in the feet under bony prominences, such as the metatarsal heads. They typically have a punched-out or undermined border. Peripheral sensory neuropathy can be documented by testing for pressure sensation with a 10-g monofilament (placed on the plantar surface at a right angle with increasing pressure until filament buckles). Patients with neuropathy have a higher pressure threshold and loss of monofilament sensation, which are associated with an increased risk of foot ulcerations. Other sensory deficits may include decreased vibratory sensation (tested with a tuning fork), decreased pinprick pain, or decreased temperature sensation. Neuropathic ulcers (Choice A) The 6-minute walk test is an assessment of functional status that measures how far a patient can walk in a standardized time. It is typically used for patients with chronic lung or heart disease or with chronic pain conditions (eg, fibromyalgia, osteoarthritis). It is not as useful for patients with diabetic neuropathy or foot ulcers. (Choice B) Peripheral arterial disease (PAD) can be assessed by calculating the ankle-brachial index (ABI). However, ABI is primarily a measure of large vessel PAD and does not accurately assess small vessel disease, which often contributes to ulcers in diabetic patients. In addition, arterial ulcers are usually located on the tips of the toes, rather than the plantar surface. ankle-brachial index (ABI) arterial ulcers (Choice C) Delayed capillary refill time (>3 seconds) indicates impaired limb perfusion and may suggest underlying peripheral arterial disease. However, delayed capillary refill is a nonspecific finding, and is also seen in hypotension or volume depletion. (Choice D) Diabetic neuropathy can affect the large nerve fibers in the lower extremities, causing decreased/absent ankle reflexes. However, the knee reflex is usually not affected. Educational objective: Risk factors for diabetic foot ulcers include diabetic neuropathy, previous foot ulceration, vascular disease, and foot deformity. Diabetic neuropathy is the most important contributing factor and is found in >80% of patients with ulcers. Monofilament testing predicts the risk of future ulcers. References: The Semmes Weinstein monofilament examination as a screening tool for diabetic peripheral neuropathy. (http://www.ncbi.nlm.nih.gov/pubmed/19595541) Prediction of diabetic foot ulcer occurrence using commonly available clinical information: the Seattle Diabetic Foot Study. (http://www.ncbi.nlm.nih.gov/pubmed/16731996) What you can't feel can hurt you. (http://www.ncbi.nlm.nih.gov/pubmed/20804930)

A 48-Year-Old Overweight Man Comes to the Physician for Evaluation