
Multifocal motor neuropathy is a rare disorder of the muscles, which causes deterioration of the muscles in the upper extremities. Through this article we will discuss the effects of this muscle disorder on the body…
The muscular system is a vital body system, whose main function is to control the movement of the body. Other functions of the muscular system consist of providing posture and structure to the body and generation of heat throughout the body. This largest system of the body is of three types – cardiac, skeletal and smooth, and consists of approximately 650 muscles which work in a synchronized manner for the proper functioning of the body. The muscular system also gets affected by a number of disorders, some of them curable while others incurable in nature.
Multifocal motor neuropathy (MMN) is a kind of muscular disorder, where the muscles in the body become weak and wasted as the condition progresses. This disorder is characterized by the weakening of muscles of the hands and affects the different muscles of the body and weakens them, since the progression of this disorder is asymmetric in nature. Though MMN is a rare autoimmune disease, for reasons unknown, it mostly affects men, in comparison to women, with the ratio being 3:1. Multifocal motor neuropathy with conduction block is a demyelinating disorder where the immune system rejects the healthy nerve cells and mistakes them for foreign bodies.
In this process, the myelin sheath, which is the protective membrane of the motor nerve cells, gets damaged. This destruction of the myelin sheath can cause a hindrance to the nerve transmissions and lead to gradual decrease in strength and stamina. This condition, which is a type of muscular dystrophy, affects only the motor nerve fibers.
Multifocal Motor Neuropathy Symptoms
Since this disorder primarily affects the hands, the first symptoms can be usually noticed in the hands. Given below are some of the signs and symptoms of MMN.
- One of the earliest symptoms of this disorder are unstable hands. The wrists may droop at the joints and the hands may lose their dexterity and grip. Since the median nerves of the hands and peroneal nerves in the legs are connected, muscle fatigue may also spread to the legs. Progression of this muscular disorder may also exhibit symptoms like weakness and immobility. , even during slight movements can be experienced.
- Fasciculations, or muscle twitching, followed by cramps are also observed in individuals suffering from motor neuropathy. Some individuals may also complain of tingling or pricking sensation in the arms, a feeling of numbness in the arms and legs, etc. apart from the above-mentioned symptoms. In pregnant women, the symptoms may become worse in nature and may also affect the fetus.
Multifocal Motor Neuropathy Treatment
This muscular disorder is often confused with amyotrophic lateral sclerosis (ALS), which is also referred to as Lou Gehrig’s Disease, that affects the nerve cells and is fatal in nature. However, there is a vast difference between both these diseases. Muscular dystrophy can be mild in nature, which may not require treatment. However, treatment is essential if the condition progresses as it may result in disability.
Treatment may involve administering immunoglobulin (Ig) intravenously. Immunoglobulin is a protein, which acts as an antibody to control the overactive immune system. Another drug which is used to treat this disorder in an effective way is cyclophosphamide, which is an immunosuppressive agent and is also administered intravenously. The prognosis of this treatment is positive with approximately more than 70 percent of the patients responding well to the treatment. They are also able to lead a normal life.
The good news is that multifocal motor neuropathy is a treatable condition and the symptoms can be brought under control. Timely medical intervention is necessary to prevent this disorder from resulting in permanent disability.