In addition, unwanted curvature of the spine, or scoliosis, is a complication that often accompanies neuromuscular conditions. It can contribute to pressure sores because it causes the individual to lean to one side, placing disproportionate weight on one buttock. Prolonged pressure from a bed or chair on one side and bone on the other makes it impossible for the affected area of skin to be properly nourished by tiny blood vessels called capillaries. The area of skin starts to die. The greater the pressure, the more likely damage will occur.
Friction is another potential cause.
Movement that causes skin to rub roughly against bedding may damage the capillaries and diminish blood supply at a particular point. Dragging someone across a surface instead of lifting the person can cause this. Excess moisture on the skin that results if the person suffers from incontinence of the bowels or bladder can also contribute to skin breakdown. Perspiration caused by wearing a brace or other orthopedic device can have a similar effect. General poor health, undernourishment and obesity are other possible factors leading to pressure sores.