Arachnoiditis

Question 1

Definition

Answer 1

Inflammation of arachnoid mater (part of meninges)

Post surgical/epidural complication

Commonly affects nerves of lumbar and thoracic spine, rarely all of spine

Arachnoiditis is rare

Question 2

Aetiology

Answer 2

Exact cause unknown, as its a rare condition with a number of possible causes

Arachnoid mater can become inflamed because of irritation from:
– complications from spinal surgery or too many lumbar punctures- 90% of cases linked
– direct injury to your spine
– infection from bacteria or viruses- meningitis, TB or HIV
– chronic compression of spinal nerves- from degenerative disc disease or advanced spinal stenosis
– preservatives found in epidural steroid injections

Question 3

Pathology

Answer 3

Affects arachnoid mater, somewhere along the spinal cord, not the brain.

Damage to and inflammation of the arachnoid (subarachnoid and subdural space) leads to a cascade of events:
– collagen deposits
– scar tissue that encloses nerve roots
– fibrosis (thickening or scarring of tissue)
– decreased cerebrospinal fluid flow
– clumping of nerve roots
– impaired blood supply to the affected nerves
– nerve atrophy
– nerve damage and possible tethered nerves

Due to these changes in the arachnoid and nerve roots, arachnoiditis frequently results in pain and possible neurological deficits, such as muscle weakness and sensory issues.

Question 4

Clinical presentation

Answer 4

Headaches

Severe shooting pain, similar to an electric shock feeling

tingling, numbness and weakness in legs

difficulty sitting for a long time, if at all

Neurogenic bladder

Bowel dysfunction

Sexual dysfunction, such as ED or vaginal dryness

Sensations that may feel like insects crawling down your legs, or water trickling down your leg

Question 5

Investigations

Answer 5

Not a reliable way of diagnosing arachnoiditis

MRI:
– look for nerve root thickening and clumping in the spine.

CT scan:
– look at vertebrae and discs

Lumbar puncture:
– draw spinal fluid, as arachnoiditis may be due to infections in the spinal fluid

Electromyogram:
– help assess the severity of the damage to the affected nerve roots by using electrical impulses to check nerve function

Question 6

Treatment

Answer 6

No cure
Trt focuses more on alleviating pain, improving patients QOL and managing symptoms.

Pain management
physical therapy (hydrotherapy)
psychotherapy
stretching and ROM exercises

Spinal cord stimulation- transmits an electrical signal to your spinal cord for pain relief

Medications- NSAID’s or stronger medications. Muscles relaxants (baclofen).