Is there anyone in the US playing tennis with an Ulna Head Inplant beside me?”
There more than likely is. Your best bet is to search out Ulna Head Implant support groups or online forums and aks the question there. Another option would be to contact some of the bigger tennis associations and present the question to them — they may dig contacts up for you. And don’t forget to contact your local news outlets — if you can add some human interest to the whole thing, they’re always looking for something to run, and a number of people will pick up on the story. Another option is to upload a quick video of yourself asking the question to YouTube and tag it with your question.