Most of the skin breakdown I’ve seen didn’t announce itself. It started quietly beneath the surface, in the same small spot, while everything still looked fine on top. By the time there’s redness to point at, the damage has usually been building for a while. Our skin is pressed into chairs and mattresses, pulled by gravity, rubbed by clothing, and exposed to heat and moisture, all while quietly holding the line. Healthy skin handles most of that without complaint. But when the same forces repeat in the same place, over days and weeks, that’s when it starts to fail, and most people don’t notice until it already has.
Two of the biggest forces behind this are friction and shear. You’ve probably felt friction, the burn or chafing from a too-tight shoe or a scratchy collar. Shear is harder to see. It works deep under the surface, stretching tissue and choking off blood flow without leaving much of a mark up top. Together, they cause some of the most common and most preventable wounds I see. Here’s how to recognize each one, and what actually keeps skin safe.
What Your Skin Is Actually Doing Every Day
Your skin is one of the hardest-working organs in your body. The outer layer, often called the skin barrier, acts as a shield between you and the outside world. It retains moisture, keeps out bacteria and irritants, and protects every structure beneath it. When it is healthy and intact, you barely think about it. When it breaks down, the consequences can range from dryness and soreness to open wounds that fail to heal for weeks or even months.
Often, this breakdown can surprise people because the skin is resilient. However, when it is repeatedly rubbed, compressed, or stretched, it begins to fail. The damage often begins on the inside long before anything is visible on the surface. Tissue injury has typically been building for some time when redness or rawness appears.
What Friction Does to the Skin
Friction occurs when skin rubs against another surface. That surface might be a bedsheet, a piece of clothing, a brace, a medical device, or even another fold of skin. The result is similar to what happens when you rub two surfaces together repeatedly, where the outer layer gradually wears away, leaving skin that is red, raw, and vulnerable to infection.
The important thing to understand about friction is that no single episode causes a wound. It is the repeated rubbing of the same spot over time that causes the damage. Think about a shirt collar rubbing the back of someone’s neck day after day. A person with limited mobility is being slid across a mattress during repositioning rather than lifted. The skin on our inner thighs rubs together during the summer. Each situation creates friction, and over time, the skin loses the battle.
Once that outer barrier is even slightly compromised, bacteria can get in. Moisture makes things worse. And healing becomes much harder, particularly for older people living with diabetes or managing other health conditions. Friction is a major contributor to the development of pressure injuries (previously known as bedsores), and its effects are significantly amplified in the presence of moisture.
What Shear Is and Why It Is So Dangerous
Shear acts beneath the skin’s surface and is often more damaging than friction. It occurs when the skin remains relatively still against a surface while our deeper tissues shift and slide in a different direction. For example, if someone is lying in a hospital bed with the head elevated. Gravity pulls the body toward the foot of the bed. The skin, pressed against the mattress, stays put, but the muscles, fat, and other tissues underneath slide downward with the skeleton. That movement stretches and twists the tiny blood vessels inside the tissue, reducing or cutting off the blood supply entirely.
This internal skin damage can be difficult to detect early and can be significant even while the skin on the surface looks nearly normal. Research has shown that internal mechanical stress during shear loading can be far greater than what is registered at the skin’s surface, meaning a small area of redness may actually represent a much deeper problem beneath the skin. When friction and shear occur together, as they very often do, the risk of a serious wound increases dramatically.
A way to help prevent this issue when in bed is to keep the head of the bed at or below 30 degrees whenever medically appropriate to reduce shear forces, particularly at the tailbone and sacrum. When elevation is necessary, strategies to prevent the body from sliding, such as a footboard or repositioning, can make a meaningful difference.
Who Is at the Highest Risk
Some people are more vulnerable to friction and shear than others. A limited ability to move independently carries a higher risk, and other risks include:
- Older adults, whose skin naturally becomes thinner, drier, and less elastic with age, making it far less capable of withstanding mechanical stress.
- Being bedbound or spending most of their day in a wheelchair.
- People recovering from surgery, a stroke, or a serious illness.
- Living with diabetes. Diabetes can impair circulation and reduce sensation, making it harder to feel when an issue is developing.
- Undergoing cancer treatment such as chemotherapy. This can make the skin more fragile and slow healing.
- Carrying extra body weight, which increases pressure at bony areas and creates more skin-to-skin friction in body folds.
However, you do not need a serious health condition for friction and shear to cause real harm. These forces can affect you daily. It could be that you are not realizing you are sliding down in a recliner while watching television. Being pulled rather than lifted during a transfer or reposition. A waistband or catheter tubing pressing on the same spot for hours. The common thread is repetition, the same force, in the same place, again and again, until the skin can no longer recover.
How Moisture Makes Everything Worse
Friction and shear rarely act alone. Moisture like sweat, urine, stool, and wound drainage, or the dampness that builds up when two skin surfaces press together in a warm fold, is almost always part of the problem and significantly increases the damage these forces can cause. The goal should be to keep it as far from the skin as possible. When skin stays wet from these sources, it softens and weakens from the outside in. Softened skin tears and breaks down far more easily under friction and shear than skin that is dry and intact.
Incontinence is one of the most challenging situations I see in this regard. If skin is repeatedly exposed to urine or stool without adequate cleansing and protection, it becomes inflamed and raw, known as incontinence-associated dermatitis. It can compound quickly because it also raises the skin’s pH and increases surface friction. Often, the skin around the buttocks, perineum, and inner thighs will deteriorate very rapidly if the skin is not consistently cared for, and can lead to pressure injuries.
How to Protect the Skin
Most skin damage from friction and shear is preventable. To help prevent skin issues, you need consistency, the right tools, and the knowledge of what to do and when.
Reposition often and always lift, never drag.
For those with limited mobility, staying in one position for extended periods is a leading risk factor for skin breakdown. Shifting position at least every two hours gives compressed tissue a chance to recover. Always lift someone when moving them in a bed. Dragging or pulling a person across a surface, even with the best intentions, creates significant friction that can damage the skin in seconds.
Keep the head of the bed as low as safely possible.
Every degree of elevation creates more downward slide and more shear. When medical needs require the head of the bed to be raised, use a footboard or repositioning wedge to prevent the body from migrating toward the foot of the mattress. Even small adjustments can meaningfully reduce the forces on the sacrum and tailbone.
Choose the right support surfaces.
The surface a person rests on matters enormously. Pressure-redistributing mattresses and seat cushions reduce both pressure and shear simultaneously. For wheelchair users, proper cushion selection and a professional seating assessment can make a big difference. These surfaces aren’t only for clinics or hospitals, but can make a real difference when used at home.
Maintain the skin’s natural hydration and protect against external moisture.
I want to draw a clear line, because “moisture” means two different things in skin care. External wetness from urine, sweat, or stool sitting on the skin’s surface is damaging, but internal moisture helps keep it flexible and able to withstand friction. When that’s low, skin becomes dry, tight, and brittle, and tears easily under pressure.
Applying lotion after bathing helps restore and lock in internal moisture. Look for ceramides, glycerin, or skin-identical lipids, which help rebuild the skin’s natural barrier. For areas exposed to incontinence or sweating, apply a barrier cream or ointment on top as a physical shield against harmful external moisture.
The lotion feeds skin from inside; the barrier cream guards it from outside. Together they support a three-part routine: cleanse, moisturize, protect.
Select gentle fabrics and surfaces.
Rough fabrics, tight waistbands, coarse seams, and stiff materials all generate unnecessary friction. Soft, loose, breathable clothing is always the better choice. For people spending significant time in bed, low-friction sheets designed specifically for this purpose are worth considering. They are more widely available than many people realize, and they can make repositioning easier while reducing the forces on the skin.
Support nutrition and hydration.
What goes into the body is just as important as what goes on the skin. Adequate protein intake is essential for skin repair and tissue regeneration. Vitamins A, C, and E, along with zinc, all contribute to skin health and wound healing. Staying well hydrated keeps the skin more supple and resilient. Clinical guidelines recommend ensuring adequate caloric and protein intake for anyone at risk for or currently managing a pressure injury, and a registered dietitian can be an invaluable partner in that process.
Place protective skin dressings on high-risk areas before a wound ever starts.
Thin foam or silicone pads are protective dressings placed on vulnerable skin to shield it from damage. They come in different shapes and thicknesses based on your specific needs. Heels, tailbone, elbows, and any skin surface in contact with a medical device are especially at risk. These easily accessible multilayered foam dressings help reduce surface friction and help absorb internal forces that can injure deeper tissue before anything is visible on the surface.
What I’d keep within reach
These are items that I have used and recommend in practice.
- Medline Comfort Glide – A sheet that helps make repositioning safer and easier for both the person and the caregiver.
- Medline Gel Foam Pressure Redistribution Cushion Seat – redistributes pressure away from bony prominences and provides increased comfort. It can be used in any chair or wheelchair.
- Mepilex Non-Bordered Foam – Soft, conformable foam that cushions a curved bony spot like the heel or sacrum. Since it has no sticky edge, you hold it in place with a light wrap or film over the top.
- Mepilex Transfer Dressing – A thin, conformable foam that you can cut to shape and place under medical tubing to cushion the skin and ease the pressure and rubbing. It molds over curves and lifts away gently when removed.
- Mepilex Border Dressing – All in one foam with a silicone adhesive edge that sticks on its own. Smooth a shaped version over a high risk bony prominence to cushion pressure and reduce the rubbing and shearing that lead to skin breakdown.
Warning Signs You Should Never Ignore
Even when you are doing everything right, it is important to know the early warning signs of skin breakdown. The sooner a problem is identified, the more easily it can be addressed. And if you ever see something that concerns you or you are unsure what you are looking at, please reach out to a wound care nurse or your healthcare team.
Redness that won’t blanch
Press gently on a red area; if the skin does not briefly lighten under your fingertip, a process called blanching, that is a warning sign and could indicate a pressure injury/bedsore. It tells you the blood flow in that tissue is not responding normally.
Warmth, firmness, or sponginess
The area may also feel warmer, slightly firmer, or softer and spongy than the surrounding skin. The person may report tenderness or aching even without direct pressure on the spot. All of these signs indicate that the tissue is under stress and that something needs to change right away.
Blisters, breaks, or deep discoloration
Blistering, open areas, or discoloration in shades of dark purple, maroon, or deep red over a bony area, is a more serious finding and warrants prompt evaluation by a healthcare provider. This could signal a deep tissue pressure injury, damage that began beneath the surface and has not yet fully declared itself. Do not wait and get it evaluated by a health care provider as soon as possible.
I can tell you from years of clinical experience: the effort you put into prevention can help prevent these serious issues and will pay off in ways that are hard to overstate. Catching a problem early is always, always better than waiting. Wounds caught in their earliest stages heal far more reliably than those that have been left to progress.