David P, Australia
I was a competitive triathlete a couple of years back and developed chronic medial knee pain from running, which persisted for a good 12-18 months. I have a desk job and as part of my knee rehabilitation I ended up spending a lot of time sitting at my desk with one or both legs propped up on a stool under my desk. This unfortunately had the effect of causing me to slouch in my chair which ended up putting a lot of pressure on my coccyx. Of course, when I noticed this, I altered my posture, but it was too late and I started to find that sitting down on almost anything caused me to have coccyx pain. Strangely, the softer the chair, the worse it was as soft cushions tended to 'ride up' my rear end and put pressure on my tail bone. Even lying flat on my back in bed caused pain.
I tried anti-inflammatories, stretches, manual manipulation, massage of the surrounding soft tissue, all to no avail. I purchased a couple of flat pillows with a coccyx cut-out at the back also - these did provide some relief but did not resolve my issue. I've had chronic pain for just over a year now.
The biggest break-through I've had is to recently purchase a lumbar support roll, which I use at work, where I sit for 8-10 hours a day. This has provided the best results so far - to the point where I can go a couple of days at a time without much, if any pain - almost back to normal. I've even started using the lumbar roll only (not sitting on the flat pillow) and even this works well.
My theory is that without the lumbar roll, I was still tending to slouch a bit in my chair, which tends to roll the back of my pelvis down and forward - of course this pushes the coccyx down into whatever I'm sitting on. The lumbar support forces you to arch your back in a normal 'S' shape which rolls the pelvis the opposite direction, moving the coccyx up and away from whatever you're sitting on. Less contact and pressure = less pain. That's my theory anyway.
Just thought I'd share this in the hope that it can help someone else.