Advice on dealing with flares please.

HI Fizzijam, Although you are very experienced in your polymyalgia pain ,the unilateral nature of your sciatica type pain may suggest the pain is originating from your back.It could be as simple as changing your mattress but worth getting your Gp to check your back for any disc or secondary osteoporosis from prednisolone, your dexa scan results could help with identifying this issue. 

"intense pain at night,all night,in left buttock traveling down left leg"

I am not a doctor, but would make a guess that you have stressed your back and that is causing the pain.  PMR pain is usually symmetrical, not only on one side.  I would suggest that you see a doctor, but you can also try to use some over the counter  meds ( like ibuprofen) to help you with your back. Just be careful to not take it within a few hours  of your pred, since both can upset stomach. 

Last thing is that you don't have a PMR flare and probably should go back to your original dose that managed PMR.

I know you probably do this already but I have a microwaveable wrap which can be tucked round my back or round my shoulders if my neck or shoulders start to ache. It’s very soothing. You can get them from Boots and it saves a packet on the heat wraps! I do hope you get this sorted out Nd agree with the others that this doesn’t sound like a flare. 

Fizzyjam I'm afraid to tell you this but I think you're looking at a back injury. I don't think this has anything to do with PMR. I do speak with some experience as I have had chronic lower back pain for 11 years. You really should see a doctor about it. Judging from the fact that you have pain traveling down your leg I'm also going to guess that you probably have a pinched sciatic nerve. Those can be quite painful. Gabapentin or pregablin are two medications they give for neuropathy which is what's happening to your leg. I would continue on your regular prednisone dosage as you go but put ice on your back rather than heat because this is a new injury and you want to reduce the inflammation which is something ice will do. Heat relaxes the muscles but your first concern is reducing the inflammation in your back. You might also want to try taking some ibuprofen or noroxin because both of those will help with the inflammation. And of course the prednisone helps too.

A doctor will probably start out with an x-ray of your lower back. From this he can only see the vertebrae. He will not be able to see the discs in your back. The disks are a jelly like donut that sits between the vertebrae giving them cushion. When one of these discs breaks open and seep out that reduces the amount of cushion between the two vertebrae causing pain. In addition when the disc bulges it can press on a nerve most of the time it's the sciatic nerve. This then causes the pain to travel down the leg. However if it's not the sciatic nerve being pinched it could be another nerve as there are many in your back. The pain may radiate around to your hips. If your pain continues they may want to do an MRI of your lower back. An MRI will show soft tissue damage such as the discs. I wish you luck on this and hope that your back pain gets better and you don't have to deal with this again.

That sounds like sciatica due to back muscles spasming because you over loaded them - that's what happens to me. I do an awkward movement to lift or pull something and wham!

I don't think the pred will "cure" it but myofascial pain syndrome is a common cause of such problems and that IS helped by pred as it is caused by the same inflammatory substances as PMR. In the meantime, warmth or ice may help - everyone is different. Ice doesn't help me, it makes the muscles spasm even more.