I'm assuming you have tendinitis, which I have as well. Pinball irritates these tendons after playing. When it gets worse, you wake up with pain from playing. I used cortisone shots to be able to play golf, but the shots wear off and I overplay pinball and am back in pain. Either a cortisone shot and moderate your pinball, or STOP PLAYING PINBALL FOR A FEW MONTHS. I've chosen shots the last few years and really want it to heal this time. So I haven't been playing golf, and have to stop playing pinball for a least 3 months for this to heal. Problem is we use these muscles all day every day for small chores. So it's either rest (recommended) or cortisone and try not to overdue it either way. Been dealing with this for years. It absolutely sucks, but will only get worse over time unless you let it heal.

I have arthritis in right wrist. Then I got tendonitis which spread to bursitis. I chose cortisone shots to play some competitive golf. And after a few years of doing that the cortisone doesn't seem to last as long as others have said. I believe rest is the long term answer. These injuries take longer to heal than most people think.