In a diabetic foot examination, which test uses a monofilament and tests four sites on each foot?

• A. Monofilament testing at four sites on each foot (one on the pad of the big toe and three on the ball of the foot).
• B. Tuning fork vibratory testing at the ankle.
• C. Pinprick pain testing with a safety pin.
• D. Temperature discrimination with hot and cold objects.

Answer: (A)

This item tests screening for protective sensation in the diabetic foot using a monofilament. A calibrated filament is pressed to four plantar sites on each foot (one on the pad of the big toe and three on the ball of the foot) to see if the person can feel it; if sensation is absent at any site, it indicates sensory neuropathy and increased risk for ulceration. The four-site monofilament test focuses specifically on the sensory input from the plantar surfaces where ulcers commonly develop, making it a targeted method for assessing nerve function relevant to foot protection. The other options measure different sensory modalities—vibration, sharp pain, and temperature—rather than the monofilament’s protective-sensation assessment.