Arachnoiditis: Symptoms, Causes, Diagnosis & Management

What Is Arachnoiditis?

Inflammation of the arachnoid mater (middle meningeal layer) surrounding spinal cord/brain. Causes chronic pain and neurological deficits.

Causes

• Spinal surgery (multiple procedures)
• Intrathecal injections (steroids, chemotherapy, contrast – historical)
• Trauma
• Infection (meningitis, TB)
• Spinal hemorrhage

Symptoms

• Pain – Burning, stabbing, electric‑shock; back, legs, perineum.
• Neurologic – Numbness, weakness, paresthesia, gait disturbance, bowel/bladder/sexual dysfunction.
• Muscle spasms/cramps
• Autonomic – Sweating, temperature dysregulation.
• Fatigue, sleep disturbance, depression/anxiety (secondary).

Diagnosis

• MRI with contrast – clumped nerve roots, “empty sac” sign, loculations.
• Clinical correlation essential (imaging findings ≠ symptoms always).

Management (Multimodal)

• Neuropathic pain meds: gabapentinoids, TCAs, SNRIs.
• Physical therapy (gentle), TENS, aquatherapy.
• Psychological support (CBT, ACT).
• Interventional: spinal cord stimulation, intrathecal pump (refractory cases).
• Surgery rarely helps; may worsen scarring.

No cure; focus on function and quality of life. Early referral to pain specialist/neurosurgeon experienced in arachnoiditis.