Erythema Ab Igne

A 55-year-old woman presents with a net-like, brownish-red reticulate rash on her lower back that has been present for 18 months. She has chronic lower back pain from lumbar degenerative disc disease and admits to using a heating pad continuously for 6–8 hours daily. Examination reveals telangiectasias within the pigmented network, mild scaling, and the eruption borders mirror the rectangular outline of the heating pad. Skin biopsy confirms erythema ab igne with epidermal hyperkeratosis, dermal melanin deposition, and elastic fiber damage. The structure marked **A** represents the primary management strategy for this condition. Which of the following is the MOST appropriate initial approach to prevent progression and allow resolution of early lesions?