Coccyx cushion: which way it goes, shapes and sizing

Who a coccyx cushion helps, and when to see a clinician

People look for a tailbone cushion after a fall, during long drives, at a desk job, or because hard chairs have become uncomfortable. The cushion changes where your weight rests. It does not treat the cause of pain.

The NHS lists a specially designed coccyx cushion among things to try at home, alongside good posture with the lower back supported and not sitting for long. Cleveland Clinic also lists donut pillows and wedge-shaped gel cushions as ways to take pressure off the tailbone.

Both say to get checked if pain has not improved after a few weeks or affects daily life. If you have had surgery, a pressure injury, or use a wheelchair all day, ask a clinician or occupational therapist which cushion suits you.

• See a doctor for tailbone pain that is not improving after a few weeks.
• Get help promptly for pain after a fall, or with a high temperature.
• Ask an occupational therapist about all-day wheelchair seating.
• Treat a cushion as a comfort aid, not a cure.

Cutout vs donut vs wedge: which coccyx cushion shape?

A cutout or U-shaped cushion is a rectangle of foam with an open notch at the back. A wedge cushion slopes from a thicker back to a thinner front, and many wedge cushions also have the rear cutout. A donut cushion is a ring with a hole in the middle.

Coccyx.org, a long-running patient information site, notes that ring cushions spread weight around the center and that most of its readers prefer a cushion with a coccyx cutout. Campbell County Health says a wedge-shaped cutout reduces the weight your coccyx bears, and that donut and U-shaped cushions can also help.

One small study points the same way. In a 2009 abstract from a Rutgers coccyx pain clinic, 55 patients tried both types; those with a preference were almost five times more likely to prefer the cutout wedge, while 42 percent preferred neither.

• Gel layers mainly change surface feel and warmth.
• Many people prefer neither shape, so keep the receipt.

How big should a coccyx cushion be? Measure the chair and the added height

Measure the seat of the chair you use most, side to side and front to back. A cushion that overhangs can tip or slide, and one much smaller than the seat leaves hard edges under your thighs.

A cushion adds its own thickness to the seat. Campbell County Health notes it lifts you a couple of inches, so your feet may no longer rest flat and desk or armrest heights change; it advises using a footrest. In a wheelchair, leg rests may need lowering.

In a car, the extra height changes headroom and your view of the road. Adjust the seat and mirrors with the cushion in place before a long trip.

• Measure seat width and depth, in inches or cm.
• Compare with the cushion's published footprint.
• Allow for two to three inches (5-8 cm) of added height.
• Use a footrest if your feet no longer rest flat.
• Recheck mirrors and headroom in the car.

How the two coccyx cushions compare

Both cushions are memory foam pads with a washable cover and a grippy base. The main difference is how much each maker publishes.

ComfiLife states its size and weight on its own product page. Everlasting Comfort lists its certifications and guarantee but no dimensions, and the Amazon listing we checked is a Large variant, so size must be read from the listing.

Which way does a coccyx cushion go? A two-minute fit check

Put the cushion on the chair with the open cutout at the back, against the backrest. Sit all the way back, upright, with your lower back against the chair. Your tailbone should be over the gap, not on the front edge of the foam.

Campbell County Health advises using the cushion on a seat with back support where you can, because slouching on it can hurt your lower back. It also warns against placing extra pillows underneath, since the uneven angle can harm your posture. On a very soft seat the foam sinks and the gap closes; Coccyx.org suggests a rigid board under the cushion instead.

For care, wash the cover as its label says. Everlasting Comfort advises spot cleaning the foam core and letting it air dry rather than soaking it. Foam feels firmer in a cold car, so give a new cushion a few days of normal use.

• Cutout to the back, every time you move it.
• Use a chair with back support; sit right back.
• No extra pillows stacked underneath.
• If the gap closes on a soft seat, add a firm board beneath.
• Stand up and move regularly; the NHS advises not sitting for long.

Common mistakes

The most common mistake is buying for the pain and forgetting the chair. A cushion that is too big, too tall or slides around is uncomfortable for different reasons.

Another is relying on a cushion while pain carries on. If sitting stays painful after a few weeks, a clinician can look for the cause and suggest what else may help.

• Turning the cutout to the front.
• Ignoring the extra seat height at a desk.
• Using a soft cushion on a sagging sofa.
• Putting off a check for pain that lingers.