Why Are Donut Cushions Bad for Pressure Relief?

Donut cushions concentrate body weight onto a narrow ring of tissue instead of spreading it across a broad surface, and that concentration can restrict blood flow to the very area the cushion is supposed to protect. The 2019 guidelines from the National Pressure Injury Advisory Panel (NPIAP) explicitly recommend against using ring or donut-shaped devices for pressure injury prevention. Yet donut cushions remain widely sold and intuitively appealing, because the hollow center does relieve the sensation of direct contact. The gap between what feels better and what actually protects tissue is the central problem.

How a Donut Cushion Creates the Problem It Claims to Solve

The logic behind a donut cushion seems sound at first glance: if a bony prominence like the tailbone is the source of pain and pressure damage, removing contact at that spot should help. And the cushion does remove contact. Sit on one and you immediately feel less pressure over your coccyx or sacrum. That sensory relief is real, and it is the reason people keep buying them.

The trouble is where the pressure goes instead. When you sit on a donut, your full body weight still has to be supported somewhere. Instead of being distributed across the entire seat surface, that weight now passes through the relatively narrow ring of the cushion. The tissue compressed against that ring bears a higher load per square centimeter than it would on a flat surface. The concern, supported by biomechanical reasoning and clinical guidelines, is that this ring of high pressure compresses blood vessels feeding the area inside the ring, potentially starving the central tissue of oxygen even though nothing is directly pressing on it.

This mechanism is sometimes described as peripheral-to-center ischemia: the donut squeezes a circle of tissue hard enough to choke off blood supply to the tissue in the middle. Even though the center of the cushion is open and not touching skin, the tissue there can still be damaged because it is not receiving adequate blood flow. The NPIAP’s recommendation against donut cushions is based partly on this concern, noting that the device “may cause tissue damage due to high pressure on the edges.”¹

The Evidence Is Thinner Than You Might Expect

Here is something that surprises most clinicians when they dig into the literature: the empirical evidence directly proving that donut cushions cause pressure injuries is actually quite limited. A detailed investigation of the published claims about ring cushions in nursing and midwifery found that the original evidence base was slim, and that successive authors citing one another had gradually inflated the strength of the claims. Over time, a small set of clinical observations and theoretical concerns was reinterpreted and repeated until it read like settled science.²

That does not mean the concern is wrong. The biomechanical reasoning is sound, and no one has published good evidence that donut cushions are safe and effective for pressure prevention. The point is more subtle: a recommendation that has been repeated in wound care textbooks and clinical guidelines for decades rests on less direct experimental proof than most people assume. It is a case where the theoretical argument was strong enough, and the potential harm serious enough, that clinical practice moved ahead of randomized trials. Given the stakes involved for immobile patients, that is a defensible position. But it is worth understanding that the recommendation is partly precautionary.

Why the Shape Matters More Than the Material

People sometimes assume that upgrading the donut’s material will fix the problem. A gel donut, a memory foam donut, an inflatable donut ring: these are all marketed as improvements. And yes, a softer material will slightly reduce the peak pressure on the ring’s edge compared to a rigid one. But the fundamental geometry has not changed. You are still channeling body weight through a ring, and the center is still cut off from the load-bearing surface. The shape is the issue, not the firmness.

Finite element modeling of a donut-shaped gel head support designed to prevent pressure ulcers on the back of the skull found the same problem in miniature. The donut shape forced the weight of the head to transfer through a narrow ring of scalp tissue, increasing rather than decreasing the risk of pressure injury to the occipital area.³ The takeaway holds whether the donut is under a patient’s head in a surgical setting or under someone’s hips in a wheelchair: the ring geometry concentrates force rather than distributing it, regardless of the material involved.

Context Changes the Risk

One nuance that gets lost in blanket recommendations is that the NPIAP guideline against donut cushions was written primarily for seated individuals. When someone sits, the pelvis concentrates weight onto a small area, and the sacrum and ischial tuberosities (the “sit bones”) are vulnerable to sustained pressure. A donut cushion in that context is working against you.

But what about lying down? The researchers behind a study of donut cushions used during open-heart surgery raised an interesting point. The sacral area, where pressure injuries commonly develop, and the thigh area, where a donut cushion mainly applies pressure in a supine patient, are anatomically different tissues. On flat, homogeneous tissue, the assumption that the ring will cause central ischemia is reasonable. On the more complex anatomy of a patient lying on an operating table, the relationship between the ring’s pressure zone and the vulnerable area is not the same as it is when sitting.¹

This does not mean donut cushions are fine for surgical patients. It means the blanket condemnation sometimes gets applied more broadly than the evidence supports, and the actual risk depends on the anatomy involved, the patient’s position, and how long the cushion is used. For most people in a seated position, which is the scenario that drives most consumer purchases, the guideline against donut cushions remains well-founded.

What Actually Works for Pressure Relief

The goal of a good pressure-relief cushion is the opposite of what a donut does: spread weight over the largest possible surface area so that no single spot bears a dangerous load. This principle is called pressure redistribution, and it is the foundation of modern seating interventions for people at risk of pressure injuries.

Several cushion types accomplish this in different ways, and studies comparing them give a sense of the trade-offs:

Memory foam: Conforms to the shape of the body and distributes pressure more evenly than a firm surface. In one pilot study comparing cushion types, memory foam produced lower peak pressure at the hip than a firm surface or an air cushion, though it shifted somewhat more pressure to the thighs.⁴
Gel cushions: Perform similarly to memory foam in pressure distribution, with the advantage of staying cooler. The same study ranked gel cushions between memory foam and air cushions for hip pressure, with gel spreading the load somewhat more evenly across the seating surface.
Air-cell cushions: Products like Roho and Vicair cushions use arrays of interconnected air cells that shift and conform as you move. A comparison of two air-filled wheelchair cushions found that one design recorded significantly fewer areas of dangerously high pressure than the other, highlighting that even within a single category the specific product matters.⁵
Foam cut-outs: Custom-shaped foam cushions with sections removed beneath bony prominences off-load those specific areas while still providing broad surface contact everywhere else. This technique has been used for decades at specialized rehabilitation centers for patients with spinal cord injuries, with good results for both pelvic stability and pressure reduction.⁶

Foam cut-outs are worth highlighting because they look superficially similar to a donut cushion: both have a hole or cavity under the vulnerable spot. The critical difference is that a foam cut-out still has a full surrounding surface distributing weight across the entire seat, with just the bony prominence floating free. A donut cushion, by contrast, removes the entire interior support surface and forces everything through the ring. The geometry of the cut-out keeps broad contact; the geometry of the donut eliminates it.

Why Comfort Signals Are Misleading

Pressure injury does not always hurt at first. In fact, the people most vulnerable to serious pressure ulcers, such as those with spinal cord injuries, diabetes-related neuropathy, or post-surgical sedation, often cannot feel the damage accumulating. For these individuals, choosing a cushion based on what feels comfortable is particularly dangerous, because the donut’s sensory relief (no contact on the painful spot) tells them exactly what they want to hear while doing the opposite of what their tissue needs.

Even for people with normal sensation, such as someone recovering from hemorrhoid surgery or coccyx bruising, the comfort signal is deceptive. Sitting on a donut cushion genuinely feels less painful because the sore area is not being compressed. But if that person sits on the cushion for hours at a desk, the ring is compressing a circle of tissue around the sore spot the entire time. Short-term use measured in minutes is unlikely to cause a pressure injury. Extended sitting for hours, day after day, while tissue is already compromised by surgery or injury, is a different story.

This disconnect between comfort and tissue health is why wound care specialists get frustrated when they see donut cushions still marketed and sold as “pressure relief” products. The marketing is not entirely false: the cushion does relieve pressure at the center point. It just moves that pressure somewhere else, and in many cases makes the overall situation worse.

Who Is Most at Risk

Not everyone faces the same level of danger from a donut cushion. A healthy young person sitting on one for twenty minutes during a long car ride is not in the same risk category as an elderly wheelchair user with thin skin, poor circulation, and reduced mobility. The risk factors that make donut cushions genuinely hazardous are the same ones that predispose someone to pressure injuries in general:

Immobility: If you cannot shift your weight frequently, sustained pressure in one spot becomes dangerous. People who are paralyzed, heavily sedated, or simply too weak to reposition themselves are most vulnerable.
Poor circulation: Conditions like peripheral vascular disease or diabetes reduce blood flow to the skin and underlying tissue, meaning even moderate pressure can cause ischemic damage faster.
Thin or fragile skin: Aging, steroid use, and malnutrition all thin the skin and reduce its ability to withstand mechanical stress.
Existing wounds: If there is already a pressure ulcer or surgical wound in the area, the tissue is compromised and far less tolerant of abnormal pressure patterns.

For a healthy person using a donut cushion briefly for coccyx pain, the realistic risk of developing a pressure ulcer is low. The clinical concern is aimed primarily at patients in hospitals, nursing homes, and wheelchairs, where sustained use on vulnerable tissue can lead to serious wounds that are difficult and expensive to treat.

Postpartum Use and Lingering Myths

Donut cushions have a long history in postpartum care. For decades, new mothers who had episiotomies or perineal tearing were given ring cushions to sit on during recovery. The logic was the same as for any painful area: keep the wound off the seat surface. The investigation of ring cushion evidence in nursing and midwifery practice found that claims about these devices causing not only pressure sores but also urinary tract infections and increased thrombosis risk in postpartum mothers had been circulating in the literature, but the empirical evidence behind those claims was thin.²

Modern postpartum care has largely moved away from ring cushions, but the reasons are a mix of genuine concern and inherited caution. The thrombosis claim, for instance, was based on the idea that a ring cushion might compress pelvic veins and impair venous return, but good evidence for that specific mechanism in postpartum women was never strong. What is more defensible is the general principle: if you need to sit comfortably after perineal surgery, a cushion that redistributes pressure broadly (like a wedge cushion or a thick, conforming foam pad) is better engineering than one that concentrates it in a ring.

How to Choose a Cushion for Coccyx or Tailbone Pain

If you are dealing with tailbone pain, post-surgical soreness, or a condition like pilonidal cyst recovery, you probably want something that takes pressure off your coccyx without creating problems elsewhere. A few practical guidelines:

A coccyx cut-out cushion is the closest safe alternative to a donut. It looks like a standard seat cushion with a small U-shaped or rectangular section removed at the back, right where the tailbone sits. The rest of the cushion still provides full contact with your thighs and most of your pelvis, so your weight is distributed broadly. Only the specific painful spot is unloaded. This is the foam cut-out principle applied to consumer cushions, and it works well for most people.

If you need more pressure redistribution than a standard foam cushion provides, gel or memory foam versions of the coccyx cut-out design add conformability. For wheelchair users or anyone sitting for many hours a day, an air-cell cushion fitted by a seating specialist provides the best combination of pressure redistribution and adjustability. These require some setup, since the air cells need to be inflated to the right level for your weight, but the pressure-mapping data consistently shows them outperforming passive cushions for high-risk patients.

Whatever you choose, the single most effective pressure-relief strategy is not a cushion at all: it is movement. Shifting your weight every fifteen to twenty minutes, even slightly, restores blood flow to compressed tissue more effectively than any static surface can. If you are able to stand and walk periodically, that is better than any cushion. The cushion’s job is to buy you time between movements, not to replace the need for them.