I used massage, hot packs, infrared, electrical muscle stimulation and combination ultrasound to relieve muscles spasms as well as acu-tens type accupuncture. I also used different herbs determined by the particular condition. Stretches are also helpful. For example, knee to chest stretches while lying on the back can be helpful. Medical doctors prescribe muscles relaxants. There are many muscle salves on the market as well. Most have balsam, wintergreen and other penetrating aromatic and antiinflammatory agents. Some have capsacian from peppers which helps to alleviate pain and spasms. Your pharmacist will help you select one. It would be much better to work with a professional such as a physical therapist or a chiropractor that does full spine and has a full complement of physiotherapy equipment. There are many highly effective methods available for treating muscle spasms while addressing the underlying causes.
So far you still have provided me with absolutely no relevant clinical information in the form of physical exam or x-ray findings so I have absolutely no idea what condition your wife's spine or what is wrong. From I have gathered so far, I suspect she had many structural issues. NUCCA is a good and safe place to start. Upper cervical adjustments can help a great deal in restoring imbalances and relieving tension in the paraspinal and quadratus lumborum muscles. Personally, I prefer a full spine and physiotherapy approach to treating strains, sprains, spasms, pain and misalignments. It helps to heal and rehabilitate irritated, inflammed and degenerated tissues.