Dear {recipientsName3},
Hope you're having a great time at work.
I'm writing this letter to inform you that I am ready to join on {to} again. As you know, I was on my medical leave starting from {absenceFrom} till {to}.
I intend to get back up to speed my position. Thank you once again for your consideration and interest in my surgery process. I am appreciated to be hired by a company like ours and I look forward to going back to work.
Best regards,
{yourName}