Stiff person syndrome (SPS) is a rare autoimmune neurological disorder that causes muscle spasms and stiffness. SPS affects the way your brain and spinal cord control muscle movements.
SPS causes you to experience uncontrolled episodes of muscle spasms and stiffness. It is a progressive disorder that can ultimately impede walking and other basic daily functioning skills.
What are the symptoms of stiff person syndrome?
Most notably, SPS causes muscle stiffness. The symptoms include:
- limb stiffness
- stiff muscles in the trunk
posture problems from rigid back muscles that can cause you to hunch over - painful muscle spasms
walking difficulties - sensory issues such as sensitivity to light, noise, and sound.
What causes stiff person syndrome?
People with SPS have antibodies that attack proteins in the brain neurons that control muscle movements. These proteins can beTrusted Source glutamic acid decarboxylase (GAD), gephyrin, or gamma-aminobutyric acid (GABA).
Stiff Person Syndrome: Symptoms, Causes, and Treatment
Medically reviewed by Heidi Moawad, M.D. — By Kristeen Cherney and Alina Sharon — Updated on December 8, 2022
Symptoms and Stages
Causes
Types
Diagnosis
Treatment
Outlook
Stiff person syndrome (SPS) is a rare autoimmune neurological disorder that causes muscle spasms and stiffness. SPS affects the way your brain and spinal cord control muscle movements.
On December 8, 2022, Canadian singer Celine Dion revealed that she has been diagnosed with SPS.
“While we’re still learning about this rare condition, we now know this is what’s been causing all of the spasms that I’ve been having. Unfortunately, these spasms affect every aspect of my daily life, sometimes causing difficulties when I walk and not allowing me to use my vocal cords to sing the way I’m used to,” Dion said in her announcement on Instagram.
What is SPS exactly? Read on to learn about the causes and treatment for this condition.
What is stiff person syndrome?
An autoimmune disorder occurs when your immune system incorrectly identifies healthy body tissues as harmful and attacks them.
SPS causes you to experience uncontrolled episodes of muscle spasms and stiffness. It is a progressive disorder that can ultimately impede walking and other basic daily functioning skills.
SPS can significantly interfere with your quality of life without proper treatment. However, it is a rare disorder affecting only about 1-2 people per millionTrusted Source. It has been described as starting between the ages of 30 and 60 and appears to be more common in females.
What are the symptoms of stiff person syndrome?
Most notably, SPS causes muscle stiffness.
The symptoms include:
- limb stiffness
- stiff muscles in the trunk
- posture problems from rigid back muscles that can cause you to hunch over
- painful muscle spasms
- walking difficulties
- sensory issues such as sensitivity to light, noise, and sound
SPS spasms can be very strong and may cause you to fall if standing. They can sometimes be strong enough to break bones. The spasms may be worse when you’re anxious or upset. Sudden movements, loud noise, or touching can also trigger involuntary spasms.
When you’re living with SPS, you may also have depression or anxiety. This may be caused by other symptoms you might be experiencing or a decrease in neurotransmitters in the brain.
The potential for emotional distress can increase as SPS progresses. You may notice the spams worsen when you’re out in public. This may lead you to develop anxiety about going out in public.
You may experience increased muscle stiffness and rigidity in the later stages of SPS. Muscle stiffness can also affect other body parts, such as your face. This can include muscles used for eating and talking. Muscles involved in breathing may also be affected, causing life threatening breathing problems.
What causes stiff person syndrome?
People with SPS have antibodies that attack proteins in the brain neurons that control muscle movements. These proteins can beTrusted Source glutamic acid decarboxylase (GAD), gephyrin, or gamma-aminobutyric acid (GABA).
The reason some people develop SPS is unknown. There are some risk factors, but not everyone who develops SPS has the associated risk factors.
SPS may co-existTrusted Source with other autoimmune diseases such as pernicious anemia, vitiligo, type 1 diabetes, celiac disease, and autoimmune thyroid disease.
SPS types
Your symptoms may vary depending on the type of SPS you have.
Focal stiff person syndrome:
This typically affects only one limb.
Jerking stiff person syndrome (progressive encephalomyelitis with rigidity). This can affect the control of your eye and head muscles.
Progressive encephalomyelitis with rigidity and myoclonus (PERM):
Similar to classic stiff person syndrome but can be associated with cancerous tumors.
Paraneoplastic-related stiff person syndrome:
This variant is associated with breast cancer, colon cancer, thyroid cancer, lung cancer, as well as Hodgkin and non-Hodgkin lymphomas.
However, it tends to manifest before the cancer itself and is caused by a different antibody than classic SPS.