The pin heads do different sizes so find the finest you can. I have had a wrist problem including thumb and I found them. Difficult to hold. If you have any small clamps try them below the seam and don't pull out until you are as close as possible to the seam. If you can put a pin in but have problem removing try a pair of pliers and grip just below the pin head.
Sorry for your injury. I hand stitched my avatar after a wrist operation and called it therapy.