I have an employee who was injured working part time at another work place. They will be out of work for three months. I need to replace this position, but I cannot continue to employ the injured worker. Is there any problems in laying this injure

I have an employee who was injured working part time at another work place. They will be out of work for three months. I need to replace this position, but I cannot continue to employ the injured worker. Is there any problems in laying this injured employee off?