Which statement best describes protective sensation testing for ulcer risk in the foot?

• A. A 5.07 monofilament is used to assess protective sensation, focusing on high weight-bearing areas.
• B. A feather and brush is more reliable than monofilaments.
• C. Protective sensation cannot be reliably tested; only reflexes matter.
• D. Heat and cold discrimination tests alone are sufficient.

Answer: (A)

Protective sensation testing checks whether a person can feel light pressure on the sole, because losing this sensation means they may not notice harmful pressure or injury that can lead to ulcers. The standard tool for this is the 5.07 monofilament, which applies about 10 grams of pressure when pressed perpendicularly to the skin. Testing several plantar sites, especially in high weight-bearing areas like under the ball of the foot and the toes, targets the spots most likely to develop ulcers if sensation is lost. If the person can’t feel the monofilament at these sites, it signals reduced protective sensation and a higher risk for foot ulcers, guiding preventive care such as off-loading and meticulous foot care.

Other methods aren’t as reliable for this purpose: a feather and brush aren’t standardized measures of pressure detection, and relying on reflexes or temperature discrimination alone doesn’t assess protective sensation enough to predict ulcer risk.