Loss of motion usually means a loss of function, too. For example, without wrist rotation, it becomes difficult to button clothes or perform basic hygiene activities. For some patients, having less pain actually improves their function even with the loss of motion. They are completely satisfied with the results.
Joint replacement for the fingers has been around for almost 40 years. Wrist replacement is a little newer. Over time, gradual improvements have been made in the way the implants are made and inserted. But the long-term results can be disappointing.
Many patients get the pain relief they hoped for, but their motion isn't much better. And if the joint was deformed before surgery, it's likely to still look deformed even with the new implant. Other problems that can occur include the implant loosening, breaking, or sinking down into the bone.
The good side of joint replacement is that if it doesn't work in the end or fails for any reason, you can still have a fusion. Many patients take the first step to have a joint replacement and go from there. Others just opt to have the joint fused.
The decision should be made knowing the risks and potential long-term results of both choices. You should take into consideration your job or lifestyle and what it is you want to do with your hands.