Can biofeedback help someone suffering muscle tension?

Yes. A type of biofeedback monitors muscle tension and can be used to help identify and relax tense muscles.
Best biofeedback. For muscle tension would be electromyogram (EMG) feedback. Other types of biofeedback may also help resolve the reasons for the tension. Look for a certified therapist at www.Bcia.Org or www.Aapb.Org.