A hand held instrument for evaluation of cutaneous sensory perception includes a body member, a rotatable head, and a testing element such as a monofilament projecting from the head member wherein the head member and the body are rotatably engaged for positioning the head member with its projecting testing element at a substantially right angle from the body and for alternatively positioning the head member with its projecting testing element in a non-testing position with the testing element extending in a protected position within an elongate channel of the body. The instrument further includes a guard member or sleeve in cooperative engagement with the body and head member to cover the elongate channel in a first non-testing position and to uncover the elongate channel in a second testing position.