Just an update - I have taken ibuprofen regularly but no improvement and today I feel incredibly fatigued. I have therefore increased from 6.5mg to 10mg and will stay at this level for at least a week provided it solves the problem.
Strangely it seems that everything but the knee hurts! Recovery has gone well and I wonder if it's gone a bit too well for PMR. I find this illness so frustrating - I can, and have, dealt with high blood pressure and pre-diabetes through diet; I have aided the knee recovery by exercise - but - when it comes to PMR it seems there is nothing I can do!
I can still raise my arms etc. but as the day wears on I become stiffer, in the neck, down the arms and across the shoulders which has made it difficult to sleep. I read a lot and at the end of the day the elbow of the arm that holds the book almost locks and is hard to straighten out. Some of this doesn't feel like the original PMR but I suppose things change. I know things need to re-align but with discomfort in neck and head it makes me wonder about GCA. Hopefully tomorrow I shall start to feel more like me.
Thanks for all your advice which is such a help and thanks for reading this.