Truncal Dystonia

Truncal dystonia impacts the muscles in the middle trunk of the body, including the chest, back, and abdominal muscles, and may be affected in both isolated (primary) and acquired (secondary) dystonia. The trunk is affected in generalized and can be affected in segmental dystonias. Truncal dystonia, sometimes referred to as axial dystonia, may also occur as an isolated focal dystonia.

Truncal dystonia can alter posture, leading to pain, difficulty with gait, and challenges to daily living. Truncal dystonia may cause changes to the spine and vertebrae, nerve impingement, and structural changes to the chest wall and abdomen.

Truncal dystonia can occur in several neurodegenerative disorders including Parkinson’s disease, amyotrophic lateral sclerosis, and multiple system atrophy. It can be caused by medications such as antipsychotics.

Truncal dystonia that causes the torso to bend forward may be classified as camptocormia, but it is important to note that not all camptocormia is dystonic. Camptocormia is characterized by forward flexion of the lower spine when standing and walking.

Truncal dystonia that causes the torso to bend to the side, often with twisting of the torso, may be called Pisa syndrome. It is often associated with neurodegenerative disease or the use of antipsychotic medications. In some cases, associated with antipsychotic medication use, symptoms may be reduced by lowering the dose, stopping or switching antipsychotic medication.

What are the Symptoms of Truncal Dystonia?

Truncal dystonia symptoms may be triggered by specific actions or tasks or may occur across numerous activities. Often, the symptoms may be reduced when the person is at rest. Symptoms may include:

• Involuntary contractions of the torso, chest, or abdomen muscles
• Forward bending of the torso
• Back extension or arching
• Torso tilting to one side
• Torso twisting
• Pulling or tightness of back, abdomen, or trunk muscles
• Or any combination of the above

How is Truncal Dystonia Diagnosed?

Diagnosing dystonia does not rely on a specific test. Instead, doctors rely on a thorough evaluation of symptoms and a neurological exam to make a diagnosis. In some cases, additional tests like a brain MRI and in this case a spine MRI may be conducted to rule out other potential causes of the symptoms, ensuring an accurate diagnosis.

What Treatments Are Available?

Botulinum neurotoxin injections may be used to reduce mild-to-moderate truncal dystonia. Botulinum neurotoxin injections may also reduce pain. Severe truncal dystonias may be treated with oral medications, intrathecal baclofen, and/or deep brain stimulation (DBS).
Symptoms tend to reduce with rest. Sensory tricks to reduce symptoms may include running, marching, dancing, placing hands in pants pockets, or tucking hands in the back waistband of pants.

What Type of Doctor Treats Truncal Dystonia?

The type of doctor that is typically trained to diagnose and treat dystonia is a neurologist with special training in movement disorders (movement disorder specialist).

How Will This Affect My Life?

Individuals with truncal dystonia are strongly encouraged to:

• Seek out the best medical care, including a multidisciplinary movement disorders team.
• Learn as much about truncal dystonia and treatment options.
• Use a multi-layered support system of support groups, online resources, friends, family and mental health professionals if needed.
• Investigate supportive therapies such as physical and occupational therapies.
• Engage with and participate in the dystonia community.