What Are Pressure Injuries of the Foot?

Sole of foot showing callus, hot spot, and ulcer.

Force or friction against the bottom of your foot causes the skin to thicken, forming a callus. If the skin keeps thickening, the callus presses up into the foot. A callus pressing into the foot may damage healthy tissue and cause a pressure injury. As healthy skin dies, a pressure injury forms. Pressure injuries may change from hot spots to infected wounds very quickly. 

Unfortunately, you may not notice the pain if you have neuropathy, a health problem that limits how much feeling you have in your feet. Diabetes is a common cause of neuropathy.

Hot spots

Red “hot” spots on the skin are signs of pressure or friction. They are a warning that you need to take care of your feet. If pressure is not relieved, a hot spot is likely to blister. Left untreated, a blister can turn into an open wound or a corn (thickened skin on top of the foot) or callus. Surgery to repair bunions or hammertoes may decrease pressure on hot spots and pressure injuries. Knee walkers can also allow you to get around without putting pressure on the affected foot. 

Pressure injuries

If a corn or callus presses into the foot, it destroys inner layers of skin and fat. Cracks and sores may form. These open wounds are pressure injuries. They provide a way for infection to enter the body. In some cases, dead skin (such as a corn or callus) may cover an open wound, making it harder to see.

Infected pressure injuries

If bacteria enter the pressure injury, infection sets in. This causes more healthy tissue to die. The infected pressure injury may begin to drain. The discharge may be white, yellow, or greenish. Some infected pressure injuries bleed or have a bad odor. The skin surrounding an infected pressure injury may become red or warm. If you think you have an infected pressure injury, call your healthcare provider right away.