- Axial or radicular pain occurs following an acute injury to the intervertebral disc.
- May be due to trauma, lifting injuries, or idiopathic.
- Cervical, thoracic uncommon
National incidence of herniated nucleolus pulposus is 1.7%.
- Majority occur in lumbar region (95% L4–L5 or L5–S1).
- Second most common occur in cervical region (C5–C6, C6–C7 most common).
- Thoracic region accounts for only 0.15% to 4.0 % of cases.
- 4.8% males older than 35 experience sciatica during their lifetime.
- 2.5% females older than 35 experience sciatica during their lifetime.
- Of all individuals, 60% to 80% experience back
pain during their lifetime.
- In 14%, pain lasts more than 2 weeks.
- Generally, males have a slightly higher incidence than females.
- Familial link to discogenic low back pain, no HLA correlation
- May be congenital link to herniation
- May be genetic link to disc degeneration in twins’ studies
- By late 20s and early 30s, nucleus pulposus loses vascular supply and dehydration/degeneration begins.
- Acute radiculopathy is caused by prolapse of a sequestered fragment of disc through a tear in the annulus fibrosis.
- Herniations, often posterolateral, incite intense irritation of nerve roots and increases in local inflammatory mediators such as proteinases, nitric acid, phospholipase A2, prostaglandin E2, and IL-6.
- Lateral (foraminal) herniations result primarily in nerve root compression and radicular symptoms.
- Dorsolateral herniations may compress the exiting nerve root and create a combination of radicular pain and motor weakness.
- Midline herniations produce primarily myelopathy.
- Minor trauma, such as lifting, bending, twisting, and vigorous athletic maneuvers, are implicated.
- Major trauma, such as motor vehicle accidents, falls, and industrial accidents, may result in herniation, especially with vertebral fractures.
- Injury may result after no identifiable traumatic event.
- Often occurs in the early hours of the day, after extended periods in recumbent position while sleeping.
Signs and Symptoms
- The history and differential diagnosis for a complaint of back pain and/or leg pain is complex.
- Generally, acute herniation is more common in younger populations.
- Patients may have a history of either back or neck pain with periodic exacerbations, or may have no history at all.
- A precipitating event or trauma often occurs, and the patient may develop symptoms immediately or gradually over several days.
- Some patients will report a “pop.”
- Complaints range from isolated back, thoracic, or neck pain, to very specific radicular pain in a single nerve root distribution. Pain often is described as sharp, shooting, or stinging. Knowledge of radiation patterns is critical to accurate assessment.
- Patients may complain of paresthesia and weakness. Symptoms often exacerbated by maneuvers that increase intraspinal or intradiscal pressure such as Valsalva, coughing, sneezing, and defecation.
- Pain often improves while supine or when activity decreases. Complaints of associated muscle spasm are common.
- Suspect cauda equina syndrome with complaint of progressive weakness, difficulty with urination, increased frequency, overflow incontinence, perianal numbness, saddle dysesthesia, and loss of rectal tone; these cases require immediate surgical referral.
- Comprehensive musculoskeletal and neurologic exam is mandatory.
- In lumbar injuries, inspection and gait analysis may demonstrate affected leg in flexed position, with patient listing away from the side of the irritated nerve root.
- Antalgic gait, with quick transfer of weight away from affected side, is seen.
- Evidence of motor weakness can be seen.
- Marked reduction in range of motion is common in cervical and lumbar regions, with loss of lumbar lordosis due to spasm.
- Tenderness to palpation, hyperesthesia, tenseness is present.
- Muscular atrophy may be present.
- Positive straight leg raise for lumbar, radicular pain on cervical foraminal compression (Spurling sign) maneuvers seen.
- Neurologic examination demonstrates weakness or loss of sensation to cold and sharp stimulus in corresponding nerve root distributions.
Note: Nerve root involvement usually is seen below the level of herniation. Example: L4–L5 herniation affects L5 nerve root.
Selective nerve root injection with local anesthetic may help establish diagnosis of radiculopathy in cases where history, imaging, and electrodiagnostic testing is unclear.
- MRI with and without gadolinium contrast
- CT myelogram in patients with MRI contraindication
- Axial CT scan
EMG/nerve conduction studies for radiculopathy, minimum of 14 days after symptoms begin.
- Mechanical pain
- Discogenic pain
- Myofacial pain
- Spinal stenosis
- Mass lesion/malignancy Myocardial infarction
- Aortic dissection
- Nonsteroidal anti-inflammatories (NSAIDs)
- Mild opioids for short-term use only Muscle relaxants
- Oral corticosteroid taper
- Tricyclic antidepressants
- Epidural steroid injection if conservative measures fail
- Transforaminal epidural or selective nerve root injection(Spinal Injections For Back Pain)
- Short- and long-term goals set
- Posture mechanics
- Hamstring, quadriceps, hip flexors, and calf stretching Lumbar stabilization
- Abdominal strengthening/pelvic tilt
- Improve range of motion
- Superficial heat and ice
- Identification and treatment of cormorbid mood disorders
- Adjustment and adaptation to injury state, to reduce further injury and optimize activity status
- Education regarding appropriate pacing of activities and avoidance of prolonged rest
Complementary and Alternative Medicine
- Generally good
- Worse prognosis if symptoms persist after conservative measures are employed
- Risk of permanent nerve injury if progressive weakness is not addressed surgically
Issues for Referral
Referral to pain physician or surgeon if conservative measures fail.
- Permanent nerve injury
- Cauda equina syndrome
- Chronic pain