PARASPINAL MAPPING - QUANTIFIED NEEDLE ELECTROMYOGRAPHY IN LUMBAR RADICULOPATHY

In the diagnosis of low back pain, the presence of a high percentage o f false positive findings on radiologic imaging studies has lead to a more definitive role for electrodiagnosis as a confirmatory test. The paraspinal muscles are a crucial part of the electrodiagnostic examina tion for radiculopathy. To date, no technique for paraspinal evaluatio n has been validated. Based on previously documented anatomical techni ques, we have designed a method of paraspinal examination termed ''par aspinal mapping'' (PM). Electromyographic (EMG) needles are placed in five carefully chosen locations and inserted in multiple directions. I ndividual scores for these insertions are added to determine a total P M sensitivity score. The first 50 studies using PM were compared to pe ripheral EMG, imaging studies, and pain drawings. Results indicate tha t the technique is easy to perform. Sensitivity scores relate well wit h these tests. In this limited and uncontrolled population, PM had hig her sensitivity for abnormalities than either peripheral EMG or imagin g studies. Because of the anatomical validity of PM, future studies ma y show it to be useful in localizing the level of radiculopathy indepe ndently from peripheral EMG, and to support clinical findings and imag ing studies.