MUSCLE AND SKELETAL PAIN: HOW BACK AND NECK PAIN ARE DIAGNOSED

Diagnosing any medical problem, including neck and back pain, depends on obtaining a good, detailed history of the problem. Based on your physician's knowledge back or neck pain, you will be asked to answer a series of questions either during your visit or in a written questionnaire sent prior to your visit. These questions provide the foundation of information that guides the steps in determining the source of your pain, or what is sometimes called the pain generator. In general, these questions will cover many points about you and your pain:

· Who are you (age, occupation, etc.)?

· What are your symptoms?

· When did the pain start?

· Why do you think the pain started?

· What were you doing when the pain started?

· What provokes the pain, or makes it worse?

· What relieves the pain, and what are you doing now to get relief?

· What is the quality of the pain (burning, aching, electric-shock-like, sharp, dull, etc.)?

· Where is the pain located?

· How intense is the pain? (Often this will involve rating your pain on a 0-10 scale, or some other measure of how severe your pain feels to you.)

· What is the timing of your pain (worse at night, or in the morning, does it get worse throughout the day, etc.)?

A second critical part of the evaluation that takes place before any medical studies are performed is the physical examination. Your physician will correlate ideas about what causes your pain by reviewing your medical history and observing how your body is working at the time of your physical exam. During the examination, he or she will look for numbness, weakness, reflex changes, reduced spinal mobility, muscle spasm, trigger points, and for signs of a more general illness, such as arthritis or blood vessel disease, which might be producing your pain.

By the time your physician has completed your history and physical examination, she or he will be 70 percent to 80 percent confident of your diagnosis. In many cases, your treatment will begin at that time. However, in certain case, particularly when your pain persists despite initial, or first line, treatment, other diagnostic tests may be ordered by your physician. These include:

Plain X-rays. The standard X-ray shows bony structure the best. X-rays are indicated when fracture, instability, tumor or infection is suspected. They also may help evaluate the extent of arthritic involvement. However, X-rays must be interpreted with caution since many spinal abnormalities that show up on X-ray are unrelated to pain syndromes. Myelography. An older diagnostic study, myelography involves X-rays being taken after a contrast material is injected by needle into the spinal fluid. Information about pressure on nerves is determined by the contrast pattern seen on X-ray. This study often is used in conjunction with Computerized Tomograpy scanning.

Computerized Tomography. Known as a CT or CAT (Computerized Axial Tomography) scanner, this instrument is shaped like a big donut and is sensitive to the density, or hardness, of tissue. Hard tissue, such as bone, appears white, soft material such as water appears black, and tissues of intermediate density are seen as shades of gray. CT scans work best for bone problems such as stenosis (narrowing around nerves or spinal cord) or arthritis.

Magnetic Resonance Imaging. Known as a MRI scanner, this instrument may be shaped like a torpedo tube or a four-poster bed, and can be very noisy with banging and tapping during the scan. It is sensitive to the hydrogen atoms in water molecules and produces finely detailed pictures of almost all the tissues of the body.

Discogram. During this procedure a small amount of contrast material is injected via needle into the center, or nucleus portion, of the disc. If the pressure in the disc, in conjunction with an abnormality in the structure of the disc, causes pain similar to the pain being diagnosed, the discogram is considered "positive." A CT scan typically is used to pinpoint the exact location and nature of the disc-related pain.

Electromyogram (EMG). Occasionally, more information about which nerve is involved is needed and an EMG is ordered. This study uses small needles or skin electrodes to measure the electrical response in muscles related to specific nerves or nerve roots. If the response in the muscle is abnormal, this can give the physician information about the status of the nerve going to that muscle. The interpretation of the EMG data is somewhat dependent on experience and should be performed by a specialist in neurology or physical medicine and rehabilitation certified to perform this type of examination

Diagnostic injections. Under the guidance of a fluoroscope (sometimes called a "C-arm" when portable), a small amount of local anesthetic is injected into the region of a nerve, nerve root or joint. If this results in even temporary relief of the symptoms, this area is a suspected pain generator.

Epidurogram. This involves injecting a contrast agent into the epidural space to observe and confirm any defects that can indicate scar tissue formation and nerve entrapment within the epidural area. This often is performed when a patient complains of post-surgical or post-disc-disruption pain.

The current recommended practice is to avoid plain X-ray studies unless a fracture, instability, tumor or infection (osteomyelitis) is suspected. Plain X-ray studies add little to diagnosis or treatment in most patients with back or neck pain. When signs of nerve involvement are present, such as numbness or weakness, recommended procedures include MRI or CT scanning, or CT scanning with the injection of a contrast material into the spinal fluid (myelography). These studies also may be considered when back pain has persisted for more than six weeks despite of good medical management. They are useful for simultaneously showing the bones, joints, discs and nerves, allowing your physician to rule in or out many possible diagnoses with fewer studies.