Researchers at the Arizona May Clinic have found that excessive focal pressure to the neck and shoulder area can damage the spinal accessory nerve, which was not previously recognized as a cause of injury to the nerve.
The spinal accessory nerve is a small nerve traveling in the back side of the upper shoulder area.
To illustrate the dangers of deep massage to the neck and shoulder area a healthy 38-year-old woman found it difficult to lift her left arm and experienced shoulder pain after a massage. When the pain and limited arm movement persisted she visited her doctor who used electromyography (EMG) to confirm injury to her spinal accessory nerve. A magnetic resonance imaging (MRI) revealed evidence of swelling in the shoulder’s trapezius muscle, which is supplied by the spinal accessory nerve.
For the following 6 weeks the woman underwent physical therapy and gradually improved, however, 2 years later, the woman still experiences mild pain and weakness in her left shoulder.
The researchers suggest that anyone experiencing pain or shoulder weakness, after a massage, should consider a visit to their physician to determine if nerve damage is the cause of their symptoms, which can be determined with an EMG test.