This episode is entitled “Why lower back hurts lying down” and the reasons covered are:

• Your position hurts your lower back
  
• Inflammation
  
• Disc swelling
  
• No distractions lying down

Your position lying down hurts your lower back

Maybe there’s a particular position in which your lower back hurts lying down. For some people it’s worse when they’re lying on their backs, for some on one side, some people on their fronts. You could have an irritation of the facet joints. Sometimes when you’re lying on your front, your lower back will drop into an arch. That can irritate the facet joints if they’re already irritable. For some people their lower back hurts only lying down, so there’s clearly a positional element to that.

Use it or lose it, but don’t abuse it. Try to avoid things that aggravate your pain. If you can lie on your left side, but lying on your right side triggers your pain, avoid lying on your right side. There’s a lot of things you can do with your legs, arms, or the use of towels pillows to pad yourself out. You may be able to overcome that positional element by the use of external support. This is the kind of pain that builds through the night. It doesn’t increase immediately.

Inflammation

When you stay still, your circulation slows down, inflammation builds up and it gets more swollen and irritable as you’ve been lying down for a few hours. This can be a reason why your lower back hurts lying down, first thing in the morning.

Disc swelling hurts your lower back lying down

If you have a bulging disc, that bulge can increase in size overnight. When you’re lying down you’ve decompressed, so the area fluid is absorbed into the disc. When you’re standing up or sitting, the disc is being compressed, so it slowly squeezes the fluid out of the disc. The disc actually get shorter. It’s at its thickest highest point first thing in the morning, as it absorbs fluid overnight, so any bulge will also increase. But it doesn’t happen instantly, disc swelling takes hours.

No distractions

This has less to do with mechanics and much more with the way your nervous system works. When you’re lying down in a dark room there are no distractions, so if you have pain, it’s going to be worse. Movement actually decreases your pain awareness. When you’re not moving, your attention will shift to areas of discomfort. It’s not actually changing what goes on in your back, it’s just that your nervous system is focusing on that sensation and magnifying it.