MRI scans emerge as vital resource in treatment of back pain

Jan 5 2009

Magnetic resonance imaging (MRI) is a growing technology providing an increasing number of clinical benefits when used in the evaluation of back pain according to an article in the January 2009 issue of the Journal of the American Academy of Orthopaedic Surgeons.

It is predicted that over the next several years, additional technical developments will allow MRI to provide even more useful orthopaedic benefits.

Co-author Victor M. Haughton, MD, department of radiology, University of Wisconsin Hospitals and Clinics, says, "Because of the many different ways to gather this important information, MRI can be used to identify or display almost every type of spinal tissue or pathology. The imaging sequence can be modified to meet many different clinical needs." Those include:

• Back pain
• Infection
• Tumor
• Trauma and vascular disease    

Researchers continue to find new ways to apply technologies that were previously used exclusively on other areas of the body. MRI which is considered safe, fast and versatile is now being used in several spinal applications such as:

• Intervertebral disk and facet joint degeneration
• Spinal canal stenosis (http://orthoinfo.aaos.org/topic.cfm?topic=A00329)
• Vascular disorders
• Trauma    

MRI scans are produced by stimulating the protons in tissues and liquids (such as fat, muscle, spinal cord, and fluid in the spine) using radiofrequency waves in the presence of a magnetic field. MRI detects the amount of energy emitted from these protons. This technology makes MRI well suited to evaluate spaces between spinal vertebrae, bone marrow, the spinal canal, and in soft tissues. Therefore MRI has been shown to be useful for almost every spinal pathology including; diseases of the spinal cord, nerve roots, vertebrae, disks and blood vessels. With MRI there is no radiation risk to the patient.

Computed tomography (CT) has also improved in resolution and scanning speed and is often the only imaging method available for patients with pacemakers, nerve stimulators, or those who suffer from claustrophobia. For these individuals, CT can provide structural information needed for diagnosis in many back pain cases. However, CT does include some exposure to radiation.

MRI, although a very important technology, should never take the place of a thorough medical history and physical examination. Also, there are often structural findings or "abnormalities" on MRI that are not clinically relevant and not necessarily related to a patient's symptoms. MRI findings must always correlate with the patient's clinical picture.

"The possibilities of magnetic resonance have not yet been realized. It is a rapidly evolving field. When we need tools to identify a possible herniated disk (http://orthoinfo.aaos.org/topic.cfm?topic=A00334), the simplest type of MR imaging or CT imaging can be used successfully. However, if you want to find out which disk is causing pain, which nerve is firing, which metabolites are present in abnormal amounts, or how well the spinal elements are functioning, MR will provide the answers," adds Dr. Haughton.