A. Etiology Both corns and calluses are keratotic hyperplasia of the skin due to long-term extrusion or friction. The appearance of corns is the size of a soybean grain, or slightly larger, like a chicken’s eye. The core of the corneal plugs penetrates deep into the skin and the tip presses on the nerve, producing pain. There are two types of corns: hard corns and soft corns. Hard corns usually occur on the dorsal or lateral side of the toes, where they are in close contact with the shoe. Soft corns, on the other hand, often occur between the toes. Callus, which arises from the same causes as corns, is a patchy keratotic thickening of the skin due to abnormal pressure, with a larger lesion, a patchy keratotic hyperplasia, and no central nucleus. It is mostly asymptomatic and does not affect function, but in severe cases it can be chapped and painful. When pain is produced it is called painful callus. In short, if corns and calluses produce significant pain, they should be noted, as they are often caused by abnormal pressure diseases, and the cause needs to be clarified and treated accordingly. Treatment Usually corns and calluses are caused by wearing inappropriate shoes, so relieving friction and pressure and changing shoes is the basis of treatment. Add soft padding to the area of increased pressure to reduce squeezing and friction. Simple treatments such as corns or pedicures can also be used to reduce symptoms. If corns and painful calluses are due to foot deformities or bony protrusions, they are very prone to recurrence, so surgical treatment is required to correct the deformity and remove the bony protrusions.