Hello, I wish I came across your post years earlier. I have insisted for years that it's exactly what happened to my husband. He came to see his family MD for a physical and was pushed a tetanus booster on him. Maybe somehow he was predisposed to it but within 2 weeks of getting the booster shot my husband started having Arthritis pain under his knees that gradually overtook his body'. It's been 10 years or so and he is still suffering. Would love to know the statistics of this happening but will probably never know.