Can an employer fire an disabled employee for not attending safety meeting when his prosthetic leg was being rebuilt?

Most people can get around without their prosthetic limbs for a time, if not as well or as comfortably as with them. If attendance at the meeting was a condition of employment and the person was at work, or had missed work without permission or suitable cause, then firing the employee may be within the employer's rights. Each jurisdiction is different, so check with someone who knows the details of the jurisdiction where this has happened or might happen.