In cryotherapy, conduction specifically refers to heat transfer from which location to which?

• A. From skin to cooling agent
• B. From cooling agent to skin
• C. From skin to air
• D. From wound to dressing

Answer: (A)

Conduction is heat transfer through direct contact from a warmer surface to a cooler one. In cryotherapy, the skin is warmer than the cooling agent (ice, a cold pack, or another cooled device), so heat flows from the skin into the cooling agent. That direct contact transfer of energy from skin to cooler material is why this is conduction. Other heat transfer modes involve air or fluid movement (convection), transfer without contact (radiation), or evaporation, which aren’t the direct-contact mechanism described here.