To diagnose your condition, your doctor will review your symptoms and conduct a physical examination.

To help diagnose the extent and severity of a brachial plexus injury, you may have one or more of the following tests:

  • Electromyography (EMG). During an EMG, your doctor inserts a needle electrode through your skin into various muscles. The test evaluates the electrical activity of your muscles when they contract and when they're at rest. You may feel a little pain when the electrodes are inserted, but most people can complete the test without much discomfort.
  • Nerve conduction studies. These tests are usually performed as part of the EMG, and measure the speed of conduction in your nerve when a small current passes through the nerve. This provides information about how well the nerve is functioning.
  • Magnetic resonance imaging (MRI). This test uses powerful magnets and radio waves to produce detailed views of your body in multiple planes. It often can show the extent of the damage caused by a brachial plexus injury and can help assess the status of arteries that are important for the limb or for reconstruction of it. New methods of high-resolution MRI, known as magnetic resonance neurography, may be used.
  • Computerized tomography (CT) myelography. Computerized tomography uses a series of X-rays to obtain cross-sectional images of your body. CT myelography adds a contrast material, injected during a spinal tap, to produce a detailed picture of your spinal cord and nerve roots during a CT scan. This test is sometimes performed when MRIs don't provide adequate information.
  • Angiogram. If your doctor suspects that the blood vessels feeding your arm might be injured, he or she might suggest an angiogram — an imaging test where contrast material is injected into an artery or vein to check the condition of your blood vessels. This information is important in planning your surgical procedure.