Have you tried knitting back and forward using a circular needle instead of straight pins? It is much kinder on shoulders and perhaps thumbs too. It got me knitting again when I had a painful shoulder.
I gave all my patterns and needles away when I developed arthritis in my thumb. But miss it too much I want to start again, but knit for just the odd half hour instead of the marathons I used to have. I cannot find the patterns anymore though, you have to buy a huge book to get to just one pattern.