A client sustained a fractured right humerus 3 days ago in a…

A client sustained a fractured right humerus 3 days ago in an automobile accident.  He had a cast applied and was instructed to follow up with the orthopedic physician.  He presents to the orthopedic office with complaints of 10/10 pain.  During the client interview he states that his fingers are tingling and he is having trouble moving them.  The nurse does not feel a pulse.  What condition should the nurse be concerned about that requires emergency measures?