Evaluation Arachnoiditis and root clumping

What Is Arachnoiditis?

Arachnoiditis is a chronic, often debilitating condition characterized by inflammation of the arachnoid mater, one of the membranes that surround and protect the spinal cord nerves. This inflammation can cause scar tissue formation and adhesions, resulting in abnormal clumping of nerve roots (known as root clumping) and impaired cerebrospinal fluid (CSF) flow. It is a progressive condition that can severely impact a patient’s quality of life.

In our clinical experience, arachnoiditis can spontaneously occur in EDS patients and ME/CSF patients, highlighting the importance of a multidisciplinary diagnostic protocol.

What Causes Arachnoiditis?

Arachnoiditis can be triggered by various insults to the central nervous system:

• Spinal surgeries, particularly repeated or intradural procedures
• Epidural injections, spinal anesthesia, or myelograms involving irritants or infection
• Chronic disc herniation, spinal stenosis
• Trauma, such as spinal injuries or falls
• Infectious processes: bacterial meningitis, tuberculosis
• Chemical irritation from contrast dyes (in older imaging techniques)
• Post-viral or post-infectious syndromes

Importantly, inflammation leads to fibrosis and thickening of the arachnoid, which causes mechanical entrapment of nerve roots.

Root Clumping: A Diagnostic Hallmark

In a healthy spine, nerve roots float freely within the thecal sac. Arachnoiditis disrupts this configuration. Root clumping impairs the normal movement and function of the nerves. It can result in constant pain, sensory disturbances, and motor deficits. Radiologically, clumping is most visible in T2-weighted MRI images and presents as the classic “empty sac” or “clustered grapes” appearance.

In some cases, the supine standard MRI does not evidence the presence of arachnoiditis or/and root clumping. In these cases, a lumbar prone MRI is extremely useful in the diagnosis. This advanced technique increases diagnostic accuracy, especially in early or occult cases.

Symptoms of Arachnoiditis

The clinical presentation varies, but symptoms are typically progressive and include:

• Severe burning or electric pain in the back and legs
• Numbness, tingling, or pins-and-needles sensations
• Muscle spasms and involuntary contractions
• Weakness or paralysis in lower limbs
• Gait imbalance and coordination difficulties
• Bladder, bowel, or sexual dysfunction

These symptoms may mimic other spinal or neurological conditions, requiring a differential diagnosis.

Diagnosis: Imaging and Functional Assessment

MRI remains the gold standard, particularly with T2 imaging. In advanced cases, findings include:

• Nerve root clumping
• Loss of normal CSF flow
• Scar tissue or thickened arachnoid membrane
• Spinal cord tethering

In addition to imaging, electromyography (EMG), somatosensory evoked potentials (SSEP), and motor evoked potentials (MEP) are vital in detecting functional nerve damage.

Immune system profiling could be considered an option in order to help identifying the underlying cause of the arachnoiditis, particularly in complex post-infectious or autoimmune presentations.

Our clinic integrates prone lumbar MRI using AI-enhanced 3T imaging and neurophysiological testing to ensure diagnostic precision. These evaluations are available through both in-person and remote consultations via drgilete.com.

Non-Surgical Treatment Options

In most cases, a conservative, multidisciplinary approach is recommended:

1. Pain Management

• Neuropathic agents: gabapentin, pregabalin, amitriptyline
• Anti-inflammatories (NSAIDs, corticosteroids)
• Opioids (reserved for severe, refractory cases)

2. Physical Rehabilitation

• Gentle stretching, hydrotherapy, posture correction
• Neuromuscular retraining to improve gait and balance

3. Neuromodulation

• Spinal cord stimulation (SCS) may provide pain relief by altering pain signals before they reach the brain
• Peripheral nerve field stimulation in targeted zones

4. Immunological Modulation

• Depending on patient phenotype, immune-modulating therapies can play a role in reducing inflammatory load.

At Promohealth, we combine these therapies within a personalized care model that includes neuroimmunology, physiotherapy, and rehabilitation.