Altered Spinal Excitability in Patients with Primary Fibromyalgia: A Case-Control Study

Area of Science:

• Neuroscience
• Clinical Medicine
• Pain Research

Background:

• Abnormal central nervous system excitability is linked to chronic pain syndromes.
• Primary fibromyalgia (FM) represents a spectrum of these conditions.
• Spinal and supraspinal mechanisms are implicated in FM pathophysiology.

Purpose of the Study:

• To investigate changes in spinal excitability in FM patients.
• To utilize the Hoffman reflex (H-reflex) as a measure of spinal excitability.
• To compare H-reflex parameters between FM patients and healthy controls.

Main Methods:

• A case-control study involving 38 FM patients and 30 healthy controls.
• Bilateral H-reflex measurements in upper (flexor carpi radialis) and lower limbs (gastrocnemius, soleus).
• Assessment of pain severity, duration, Widespread Pain Index, Symptom Severity Scale, depression, anxiety, and quality of life.

Main Results:

• FM patients showed a significant increase in the Hmax/Mmax ratio compared to controls.
• No significant correlation was found between Hmax/Mmax ratio and pain measures or quality of life.
• FM patients reported higher levels of depression and anxiety than controls.

Conclusions:

• Increased spinal excitability is present in FM patients, extending beyond localized pain areas.
• Findings support the central sensitization hypothesis in fibromyalgia.
• This spinal excitability measure may contribute to FM diagnosis.