According to Orphanet, the portal for rare diseases and orphan drugs, the peak incidence is around age 45 and symptoms evolve over months or years.

Muscle stiffness often fluctuates (meaning it gets worse then better) and usually occurs at the same time as muscle spasms.

These spasms can occur randomly or be triggered by a variety of different events, including a sudden noise or light physical contact.

If left untreated, RPS can potentially progress to difficulty walking and significantly impact a person's ability to perform routine daily tasks.

Although the exact cause of this syndrome is unknown, it is believed to be an autoimmune disease and sometimes occurs with other autoimmune diseases.

The diagnosis is essentially based on clinical observation and is confirmed by the demonstration of certain characteristic antibodies and electromyographic abnormalities (an essential examination of neurological diseases, editor's note).

A CT scan of the spinal cord can help rule out mechanical causes such as the presence of a herniated disc or a cyst in the spinal cord.

The first cases were documented in 1956. Stiff person syndrome has been described in the medical literature under many different names.

Originally described as stiff-man syndrome, the name has been changed because the disorder can affect people of any age and both genders.

In fact, most people with the disease are women.

It is an extremely rare disease.

According to the American organization NORD, which aims to provide support for people with rare diseases, the incidence is around 1 person in a million.

Treatment aims to relieve the specific symptoms that occur in each individual, which often requires non-drug approaches (stretching, heat therapy, aquatherapy, massage therapy, acupuncture, etc.).

Certain medications can also be used to treat muscle stiffness and episodic spasms.

© 2022 AFP