Brachial Plexus Injury

If your healthcare provider suspects you have a brachial plexus injury, they’ll perform a comprehensive examination to diagnose the injury and determine whether you have any other injuries, which is common in forceful events that result in brachial plexus injuries.

Your provider will examine all the nerve groups involved with the brachial plexus to identify the specific location of the nerve injury and its severity. The pattern by which nerves from the brachial plexus control different muscles of your arm and hand will help your provider identify potential sites of nerve injury.

If your newborn shows signs of a brachial plexus injury, their provider will perform a physical exam to see if your baby can move their upper or lower arm or hand. Their affected arm may flop when their provider rolls them from side to side. The Moro reflex (startle response) is also absent on the side of the injury.

What tests will be done to diagnose a brachial plexus injury?

Your healthcare provider may perform several tests to help diagnose a brachial plexus injury and to check for other possible injuries. These tests include:

• X-rays: This imaging test creates clear pictures of dense structures, like bone, using small safe amounts of radiation. You’ll likely get X-rays of your neck, chest, shoulder and arm to rule out associated bone fractures, especially as brachial plexus injuries typically happen from traumatic injuries.
• Computed tomography (CT) myelogram scan: A CT myelogram scan shows structures inside your body by using X-rays and computers to produce images with a special dye injection around your spinal nerves. Providers consider this imaging test the most reliable test for detecting spinal nerve avulsion injuries. Some providers may also use magnetic resonance imaging (MRI) instead of, or in addition to, a CT scan.
• Electrodiagnostic exams: These tests, which include electromyograms and nerve conduction studies, measure nerve conduction and muscle signals. They can confirm the diagnosis of a brachial plexus injury, locate the nerve injury, reveal its severity and help assess the rate of nerve recovery. Your provider will likely do a baseline electrodiagnostic exam three to four weeks after your injury. This allows any nerve degeneration that may happen to become detectable. Your provider will then repeat the exam two to three months after the initial exam and then repeatedly over time to assess whether the nerves are recovering.

If your newborn infant shows signs of a brachial plexus injury, their provider may request an X-ray of their collarbone to see if it’s fractured.

Neonatal brachial plexus injuries can mimic a condition called pseudoparalysis. This happens when an infant has a fracture and isn’t moving their arm because of pain, not because they have nerve damage.