Motor neurone disease is the condition where messages from the motor neurones, which help carry electrical impulses from stimuli and sensory neurones, begin to stop reaching the muscles, preventing response. Stimuli include anything from sound, touch, smell, and even taste, which then allow an appropriate response, such as moving your hand away from a boiling object. In motor neurone disease (or MND), muscles, which are effectors in the stimuli-response cycle, meaning they put the response into action, begin to stiffen and waste away. Behavior and mental ability can also be affected. The disease is very uncommon, affecting roughly 5000 in the UK at any time, and can cause different symptoms in each patient.
Causes
The causes of motor neurone disease are currently unknown. There is no clear hereditary link, although you are more likely to suffer from MND if a close relative has had the disease. MND is much more common in those over 50 and with other conditions, such as specific types of dementia.
Symptoms
- Weakness in the legs and ankles as well as trouble climbing stairs and more frequent trips and falls
- Speech difficulty, including slurring as well as trouble swallowing and inability to express yourself through gestures and body language
- Difficulty gripping items such as pens, opening jars, and often dropping things
- Muscle cramps and tingling
- Weight loss due to muscle decay, which can cause thinning of arms and legs in particular
- Inability to control laughter or tears in inappropriate situations
- Changes to saliva consistency or volume
- Weakened coughing, causing difficulty as unable to remove saliva
- Difficulty breathing, leading to fatigue
Types
- Amyotrophic lateral sclerosis (ALS)- the most common form of MND that causes muscle wastage
- Bulbar onset MND or Progressive bulbar palsy (PBP)- less common than ALS and affects the muscles in the face, throat, and speech, causing slurring and difficulty swallowing
- Progressive muscular atrophy (PMA)- affects a very minute proportion and causes problems with the hands and grip
- Primary lateral sclerosis (PLS)- highly uncommon and causes muscle stiffness and selected speech problems and is not usually life-shortening due to very slow progression
What can Motor Neurone Disease be Misdiagnosed as?
Motor Neurone Disease can sometimes present very similarly to Kennedy’s Disease or SBMA. Kennedy’s disease also affects the motor neurones and can cause muscle weakness and wastage, although additional hormonal problems may contribute. These two diseases are often confused at diagnosis, however, those with Kennedy’s disease usually live a normal lifespan. Problems with inflammation of the spinal cord, nerve damage, and muscle damage can also mimic MND, as well as strokes. It is vital to contact a GP as soon as symptoms of MND are observed for diagnostic tests
How is it Diagnosed?
- Blood and urine tests can show rises in creatinine kinase, which is produced due to muscle wastage
- MRIs can prove that symptoms are not caused by another condition such as a stroke
- Electromyography (EMG) and nerve conduction study (NCS) to show how electrical impulses and nerve function is working
- Muscle biopsies to disprove other muscular conditions
- Spinal taps and lumbar punctures can also rule out other conditions
Treatment
Although there is no way to treat the disease itself, there are ways that patients’ quality of life can be improved and day to day actions facilitated. Riluzole is a drug that has been proven to slightly slow down the progression of motor neurone disease, despite it still not being a cure. Specialized clinics with nurses and occupational therapists can help motor neurone disease sufferers. Regular physiotherapy can also help to combat muscle weakness, stiffness, and pain. In a more holistic approach, speech therapists and dieticians can also be involved in patient care to offer advice.
Emotional support can also be vital for those with motor neurone disease and carers can be one way to allow sufferers to remain living independently. Joining groups and forums, such as the one run by the “Motor Neurone Disease Association”, can help to have advice and support from others who also have the disease. Organizations such as this can also offer financial support for those with motor neurone disease and advise as to where sufferers can seek professional help from hospitals who have expertise in motor neurone disease.
References
“About MND.” StackPath, http://www.mndassociation.org/about-mnd/.
“Motor Neuron Disease: Types, Symptoms, Causes, and Treatments.” Medical News Today, MediLexicon International, http://www.medicalnewstoday.com/articles/164342#treatment.
“Motor Neurone Disease.” NHS Choices, NHS, http://www.nhs.uk/conditions/motor-neurone-disease/.
Youth Medical Journal 