Motor neurone disease is diagnosed based on a patient’s symptoms, any family history of the disease, a physical examination and a battery of tests to rule out other conditions.
Symptoms usually worsen gradually over a period of months after initial onset. One of the most common symptoms to first present is a weakness of grip that makes it difficult to pick up or hold objects and a person affected by the condition may find they are suddenly starting to drop things. In addition, they may find it difficult to raise their hands above their head due to weakness that develops in the shoulder muscle and may complain of difficulty combing their hair, for example. Weakness in the ankle also causes “drop foot,” where the patient develops a tendency to fall or trip easily due to weakness in the lower limbs.
Diagnosing the condition can be complicated due to the symptoms shared with other conditions such as a trapped nerve in the spine or damage to the nervous system caused by diabetes.
There is no one single test that can diagnose motor neurone disease and diagnosis usually involves a series of tests to rule out other conditions that could be causing symptoms.
An outline of the tests that may be performed is given below:
Blood tests are carried out for a variety of reasons and to check all of the organs are functioning normally.
Magnetic resonance imaging (MRI) is used to create detailed images of the brain and spinal cord.
Electromyography (EMG) is performed to assess the electrical activity within the muscles and provide clues about the motor neurone function.
A lumbar puncture may be performed to test cerebrospinal fluid and check for nerve inflammation.
Muscle biopsy may be performed in some cases to rule out muscle disorders.
Reviewed by Sally Robertson, BSc