REFERRED MUSCLE PAIN

(also called PSEUDORADICULOPATHY or PSUEDORADICULITIS)

Summary

 It is common for patients with spine pain to have pain, numbness and tingling that radiates from the neck into the arms, or from the back into the legs.  This can mean a pinched or diseased nerve in the spine from a disc herniation or other problem, but sometimes not.  Often, the pain and or numbness in the arm or leg is referred from painful muscles.  This can be overlooked, it can be misdiagnosed as nerve pain, and the purpose of this information is to reduce the chance that referred muscle pain (called "pseudoradiculopathy") will be overlooked or misdiagnosed as nerve pain (or real radiculopathy).    Here is information to help you understand how pain from muscles can imitate nerve pain.

Muscle pain 

Anytime the spine is injured, for example the neck in a whiplash injury, the muscles near the spine will work hard to splint the painful part of the spine.  If the spine injury does not get better in a few days, this constant strain on the muscles causes the muscles themselves to hurt - muscle pain is the result.  The same is true for shoulder injuries, back injuries, etc - they will lead to "secondary muscle pain".

When muscles hurt, there is soreness in the area of the affected muscle, of course.  Using the muscle will hurt, too - for example, in a whiplash injury to the cerical spine, the trapezius muslce is overworked as it is commanded by the nervous system to tighten and protect the injured neck. 

This muscle becomes sore, and shrugging the shoulders or lifting the arm will provike pain in the muscle along the top and back of the shoulder.  The muscle will also be tender to press on.  But there is something else that happens: there is often referred pain  from the muscle - pain that feels like it is coming from a part of the body far away from the muscle that is hurting.

Referred pain from muscles

Example 1: Referred pain from neck and shoulder muscles is often felt in the arm.  There can even be a sensation of numbness and tingling.  There will not be weakness with referred pain, however.  Weakness is a sign of a problem with the nerves and needs ugent attention.

Painful neck muscles that "refer" pain to the arm in the areas shaded red.  The muscles causing the referred pain are marked with "X".  Pain is felt down the arm, although the actual painful muscle is in the neck.  Notice how the pattern of muscle pain referral looks a lot like pain from a pinched nerve in the neck, specifically a pinched C6 nerve root shown below:

                                

This idea of muscle pain referring to the arm is familiar to anyone who has taken the Basic Cardiac Life Support/ CPR class from the Red Cross.  We are taught that pain from a heart attack, meaning pain in the heart muscle, refers to the left arm - and can be associated with a feeling of arm numbness.  Muscles in the neck can do the same thing - refer pain to the arm.

Example 2: Referred pain from muslces in the hip and buttock is often refered to the leg, again many patients report numbness and tingling with the leg pain.  Again, weakness in the leg would suggest a different problem, not muscle pain.

Puting it all together  

The sequence of events that leads to referred muslce pain which imitates radiculopathy and radiculitis can look like this:

Injury to the spine that does not get better quickly (example: an injury to cervical facet joints in a whiplash accident)

Muscles tighten to splint the painful spine

Muscle pain from chronic overuse of the muscles

Referred pain from muscle to arms or legs

When one looks at it this way, it becomes clear that the best way to eliminate the referred muscle pain in this sequence of cause and effect is to reduce the spine pain that is causing the muscle pain.

Conclusion

Pain radiating down the arm or leg due to a pinched or diseased nerve root is called "radiculopathy" or "radiculitis".  However, referred pain from a painful muscle in the neck area can cause pain symptoms in the arm and hand that feel exactly like a pinched or diseased nerve root to the patient, and painful muscles in the buttock and hip area can cause pain symptoms radiating down the leg that feel to the patient exactly the same as a pinched nerve in the lumbar spine.  This refeered muscle pain can imitate  nerve injuries.  It is sometimes called "psudoradiculopathy" or "pseudoradiculitis".  It is important to know about because treatments of nerve problems such as nerve pain medications,  nerve injections, and spine surgeries will not help if the source of pain is overworked muscle   Treatment of muscle pain is different from treatment of nerve pain.  For example, massage therapy may be the most effective treatment for muscle pain! 

If you have pain radiating from the neck down the arm - without arm weakness; or pain from the back or buttock radiating down the leg - without leg weakness, your doctor will need to figure out which problem you have in order to treat you successfully: muscle pain or pinched nerve. 

A careful physical exam that includes neurological exam and feeling the muscles is the way to tell them apart, sometimes supplemented by imaging studies like MRI or CT scan, and occasionally EMG/NCV tests.