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Lumbar Herniated Nucleus Pulposus

(Herniated Lumbar Disk; Ruptured Lumbar Disk; Prolapsed Intervertebral Disk)


Peter J. Moley

, MD, Hospital for Special Surgery

Reviewed/Revised Oct 2022
Topic Resources

Herniated nucleus pulposus is prolapse of an intervertebral disk through a tear in the surrounding annulus fibrosus. The tear causes pain due to irritation of sensory nerves in the disk, and when the disk impinges on an adjacent nerve root, a segmental radiculopathy with paresthesias and weakness in the distribution of the affected root results. Diagnosis is usually confirmed by MRI or CT. Treatment of mild cases is with analgesics, activity modification, and physical therapy. Bed rest is rarely indicated. Patients with progressive or severe neurologic deficits, intractable pain, conservative treatment failure, myelopathy, or cauda equina syndrome with associated sphincter dysfunction may require immediate or later elective surgery (eg, diskectomy, laminectomy).

Spinal vertebrae are separated by fibrocartilaginous disks consisting of an outer annulus fibrosus and an inner nucleus pulposus. When degenerative changes (with or without trauma) result in protrusion or rupture of the nucleus through the annulus fibrosus in the lumbosacral or cervical area, the nucleus is displaced posterolaterally or posteriorly into the extradural space.

Herniated disks are common.

Symptoms and Signs of Lumbar Herniated Nucleus Pulposus

Herniated disks often cause no symptoms, or they may cause symptoms and signs in the distribution of affected nerve roots. Pain usually develops suddenly, and back pain is typically relieved by rest and activity modification. In contrast, nerve root pain caused by an epidural tumor or abscess begins more insidiously, and back pain is worse at night while in bed.

Cauda equina compression often results in urine retention or incontinence due to loss of sphincter function.

In patients with lumbosacral herniation, coughing, sneezing, and activities such as sitting and bending forward increase the pain.

Diagnosis of Lumbar Herniated Nucleus Pulposus

  • MRI or CT

Diagnosis is usually suspected during a history and physical examination and confirmed by MRI or CT.

The physical examination should include the an evaluation of strength, sensation, and reflexes. Tests for dural tension should also be done.

On examination, with the patient in supine with legs extended, raising the leg may cause pain to radiate down the posterior thigh to below the knee (straight leg-raising test). Pain can be bilateral with central disc herniation.

Straightening the knee while sitting can produce similar pain (sitting straight-leg raising test). A variation of this test in which straightening the knee with the patient sitting and bending forward at the waist with the foot dorsiflexed is called the slump test.

In upper lumbar disc herniation (L1-2, L2-3), extending the leg at the hip with the patient prone can cause pain radiating into the anterior thigh (femoral stretch test).

Achilles tendon and patellar reflexes may be diminished or absent.

MRI or CT can identify the cause and precise level of the lesion. Rarely (ie, when MRI is contraindicated and CT is inconclusive), CT myelography is necessary. Electrodiagnostic testing may help identify the involved root.

Because an asymptomatic herniated disk is common, the clinician must carefully correlate symptoms with MRI abnormalities before invasive procedures are considered.

Treatment of Lumbar Herniated Nucleus Pulposus

  • Conservative treatment initially

  • Invasive procedures, sometimes including surgery, if neurologic deficits are progressive or severe

Because a herniated disk desiccates and shrinks over time, symptoms tend to abate regardless of treatment. Up to 85% of patients with back pain—regardless of cause—recover without surgery within 6 weeks.

Conservative treatment

Treatment of a herniated disk should be conservative unless neurologic deficits are progressive or severe. Heavy or vigorous physical activity is restricted, but ambulation and light activity (eg, lifting objects < 2.5 to 5 kg [about 5 to 10 lb] using correct techniques) are permitted as tolerated; prolonged bed rest and traction are no longer indicated.

Acetaminophen, nonsteroidal anti-inflammatory drugs (NSAIDs), or other analgesics should be used as needed to relieve pain. If symptoms are not relieved with nonopioid analgesics, corticosteroids can be given systemically or as an epidural injection; however, analgesia tends to be modest and temporary. Oral methylprednisolone may be given, tapered over 6 days, starting with 24 mg daily and decreased by 4 mg a day.

In selected patients, gabapentin and amitriptyline are often used for refractory neuropathic pain.

Physical therapy and home exercises can improve posture and strengthen back muscles and thus reduce spinal movements that further irritate or compress the nerve root.

Invasive procedures

Invasive procedures should be considered for the following:

Immediate surgical evaluation is needed if clinical findings of spinal cord compression correlate with MRI abnormalities.

Microscopic diskectomy and laminectomy with surgical removal of herniated material are usually the procedures of choice. Percutaneous approaches to remove bulging disk material are still being evaluated.

Dissolving herniated disk material with local injections of the enzyme chymopapain is not recommended.

Key Points

  • Herniated lumbar disks are common and usually affect nerve roots at L5 or S1.

  • If symptoms develop suddenly and back pain is relieved with rest, suspect a herniated disk rather than an epidural tumor or abscess.

  • Recommend analgesics, light activity as tolerated, and exercises to improve posture and strength; however, if pain or deficits are severe or worsening, consider invasive procedures.

Drugs Mentioned In This Article

Drug Name Select Trade
7T Gummy ES, Acephen, Aceta, Actamin, Adult Pain Relief, Anacin Aspirin Free, Apra, Children's Acetaminophen, Children's Pain & Fever , Comtrex Sore Throat Relief, ED-APAP, ElixSure Fever/Pain, Feverall, Genapap, Genebs, Goody's Back & Body Pain, Infantaire, Infants' Acetaminophen, LIQUID PAIN RELIEF, Little Fevers, Little Remedies Infant Fever + Pain Reliever, Mapap, Mapap Arthritis Pain, Mapap Infants, Mapap Junior, M-PAP, Nortemp, Ofirmev, Pain & Fever , Pain and Fever , PAIN RELIEF , PAIN RELIEF Extra Strength, Panadol, PediaCare Children's Fever Reducer/Pain Reliever, PediaCare Children's Smooth Metls Fever Reducer/Pain Reliever, PediaCare Infant's Fever Reducer/Pain Reliever, Pediaphen, PHARBETOL, Plus PHARMA, Q-Pap, Q-Pap Extra Strength, Silapap, Triaminic Fever Reducer and Pain Reliever, Triaminic Infant Fever Reducer and Pain Reliever, Tylenol, Tylenol 8 Hour, Tylenol 8 Hour Arthritis Pain, Tylenol 8 Hour Muscle Aches & Pain, Tylenol Arthritis Pain, Tylenol Children's, Tylenol Children's Pain+Fever, Tylenol CrushableTablet, Tylenol Extra Strength, Tylenol Infants', Tylenol Infants Pain + Fever, Tylenol Junior Strength, Tylenol Pain + Fever, Tylenol Regular Strength, Tylenol Sore Throat, XS No Aspirin, XS Pain Reliever
A-Methapred, Depmedalone-40, Depmedalone-80 , Depo-Medrol, Medrol, Medrol Dosepak, Solu-Medrol
Active-PAC with Gabapentin, Gabarone , Gralise, Horizant, Neurontin
Elavil, Tryptanol, Vanatrip
NOTE: This is the Professional Version. CONSUMERS: View Consumer Version
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