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abnormal protrusion of an organ or other body structure through a defect or natural opening in a covering membrane, muscle, or bone. (See also hernia.)
Herniation syndromes. From Ignatavicius and Workman, 2002.
caudal transtentorial herniation transtentorial herniation.
central herniation a downward shift of the brainstem and the diencephalon due to a supratentorial lesion, causing Cheyne-Stokes respirations with pinpoint nonreactive pupils.
cingulate herniation a shift of the cingulate gyrus to below the falx cerebri.
disk herniation (herniation of intervertebral disk) (herniation of nucleus pulposus) herniated disk.
tentorial herniation transtentorial herniation.
tonsillar herniation protrusion of the cerebellar tonsils through the foramen magnum.
transtentorial herniation downward displacement of medial brain structures through the tentorial notch by a supratentorial mass, exerting pressure on the underlying structures, including the brainstem; this is a life-threatening situation because of pressure on the third cranial nerve, with symptoms including dilated, nonreactive pupils, ptosis, and a decreased level of consciousness. Called also caudal transtentorial herniation, tentorial herniation, and uncal herniation.
uncal herniation transtentorial herniation.


Protrusion of an anatomic structure (for example, intervertebral disk) from its normal anatomic position.
Farlex Partner Medical Dictionary © Farlex 2012


 A bulging of tissue through an opening in a membrane, muscle or bone. See Brain herniation, Cerebellar herniation, Disk herniation.


Protrusion of an anatomic structure (e.g., intervertebral disc) from its normal anatomic position.
Medical Dictionary for the Health Professions and Nursing © Farlex 2012


The displacement of body tissue through an opening or defect.

cerebral herniation

Downward displacement of the brain (usually as a result of cerebral edema, hematoma, or tumor) into the brainstem. The resulting injury to brainstem functions rapidly leads to coma, nerve palsies, and death if treatment is ineffective.
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herniation of nucleus pulposus

Prolapse of the nucleus pulposus of a ruptured intervertebral disk into the spinal canal. This often results in pressure on a spinal nerve, which causes lower back pain that may radiate down the leg, a condition known as sciatica. illustration;

Patient care

A history is obtained of any unilateral low back pain that radiates to the buttocks, legs, and feet. Almost all herniations occur in the lumbar and lumbosacral region; 8% in the cervical region and only 1% to 2% in the thoracic region. When herniation follows trauma, the patient may report sudden pain, subsiding in a few days, then a dull, aching sciatic pain in the buttocks that increases with Valsalva's maneuver, coughing, sneezing, or bending. The patient may also complain of muscle spasms accompanied by pain that subsides with rest. The health care professional inspects for a limited ability to bend forward, a posture favoring the affected side, and decreased deep tendon reflexes in the lower extremity. In some patients, muscle weakness and atrophy may be observed. Palpation may disclose tenderness over the affected region. Tissue tension assessment may reveal radicular pain from straight leg raising (with lumbar herniation) and increased pain from neck movement (with cervical herniation). Thorough assessment of the patient's peripheral vascular status, including posterior tibial and dorsalis pedis pulses and skin temperature of the arms and legs, may help to rule out ischemic disease as the cause of leg numbness or pain.

The patient is prepared for diagnostic testing by explaining all procedures and expected sensations. Tests may include radiographic studies of the spine (to show degenerative changes and rule out other abnormalities), myelography (to pinpoint the level of herniation), computed tomography scanning (to detect bone and soft tissue abnormalities and possibly show spinal compression resulting from the herniation), magnetic resonance imaging (to define tissues in areas otherwise obscured by bone), electromyography (to confirm nerve involvement by measuring the electrical activity of muscles innervated by the affected nerves), and neuromuscular testing (to detect sensory and motor loss as well as leg muscle weakness).

Pain and its management are often crucial elements of care; levels of pain are monitored, prescribed analgesics are administered, the patient is taught about noninvasive pain relief measures (such as relaxation, transcutaneous nerve stimulation, distraction, heat or ice application, traction, bracing, or positioning), and the patient's response to the treatment regimen is evaluated. During conservative treatment, neurological status is monitored (esp. in the first 2 to 3 weeks after beginning treatment) for signs of deterioration, which may indicate a need for surgery. Neurovascular assessments of the patient's affected and unaffected extremities (both legs or both arms) are performed to check color, motion, temperature, sensation, and pulses. Vital signs are monitored, bowel sounds are auscultated, and the abdomen is inspected for distention. The disorder and the various treatment options are explained to the patient, including bedrest and pelvic (or cervical) traction, local heat application, a physical therapy designed exercise program, muscle-relaxing and anti-inflammatory drug therapy, injection of local anesthetic and steroid drugs, acupuncture, and surgery.

Both the patient and family are encouraged to express their concerns about the disorder; questions are answered honestly, and support and encouragement are offered to assist the patient and family to cope with the frustration of impaired mobility and the discomfort of chronic back pain. The patient is encouraged to perform self-care to the extent that immobility and pain allow, to take analgesics before activities, and to allow adequate time to perform activities at a comfortable pace.

Walking and gentle stretching are encouraged as part of daily exercise during conservative therapy. If the patient is restricted to bedrest (or in traction), the patient should increase fluid intake and use incentive spirometry to avoid pulmonary complications. Skin care and a fracture bedpan are provided if the patient is not permitted bathroom or commode privileges.

For patients who require surgery, the patient is prepared physically and psychologically for the specific procedure (laminectomy, spinal fusion, microdiskectomy) and postoperative care regimen, and informed consent is obtained. The patient may donate blood prior to surgery for later autotransfusion as needed.

Postoperative Care: Bedrest is enforced for the prescribed period, the blood drainage system in use is managed, and the amount and color of drainage are documented. Any colorless moisture or excessive drainage should be reported; the former may indicate cerebrospinal fluid leakage. A log-rolling technique is used to turn the patient from side to side, and the patient is taught how to turn in this manner when moving about or getting up from bed at home. Analgesics are administered as prescribed, esp. 30 min before early attempts at mobilization. The health care professional assists the patient with prescribed mobilization. Depending on the surgery required, the patient may require a back brace (individually fitted) for a period of time after surgery, and this is carefully fitted and the patient taught about its use.

Before discharge, proper body mechanics are reviewed with the patient: bending at the knees and hips (never the waist), standing straight, and carrying objects close to the body. The patient is advised to lie down when tired and to sleep on the side or back (never on the abdomen) on an extra-firm mattress or a bed board. All prescribed medications are reviewed, including dosage schedules, desired actions, and adverse reactions to be reported. Referral for home health care or physical/occupational therapy may be necessary to help the patient manage activities of daily living.


tonsillar herniation

The protrusion of the cerebellar tonsils through the foramen magnum. It causes pressure on the medulla oblongata and may be fatal.

transtentorial herniation

A herniation of the uncus and adjacent structures into the incisure of the tentorium of the brain. It is caused by increased pressure in the cranium.
Synonym: uncal herniation

uncal herniation

Transtentorial herniation.
Medical Dictionary, © 2009 Farlex and Partners


Medical Dictionary for the Dental Professions © Farlex 2012

Patient discussion about herniation

Q. do you know of a good gastro doctor in staten island ny. I have acid refex so bad cant sleep, or lay flat.. years ago was told I had a hiatus hernia, and would only have fLare ups once in a while, have taken nexium for years, and it worked, but not anymore.. I really need to find a good doctor to test me again.

A. yazmine, if you want, you can try consume daily yogurt with a little apple cider vinegar in it (just add 5ml of ACV in your yogurt). some of gastric problems are believed to be caused by some bacteria. apple cider vinegar will help regulate the normal condition inside your gastric mucosa, so that for the long run it probably can help improve your condition.

Q. I have a low back pain that radiates to my leg when i pick up stuff. Is it a disc herniation? I am a 43 years old bank teller. During the past 5 months I've suffered from a low back pain. The pain is not very strong, but it gets much worse while doing physical activity. When i walk or lift heavy things the pain is even stronger, and it radiates to my left leg. Can it be signs for disc herniation?

A. It's possible that you have a nerve impingement from a disc herniation, but not necessarily so. What you need to know is that even if you have a herniated disc, the question is what would the recommended treatment be?
90% or more of herniated discs resolve without surgical treatment within 6 months. MRI imaging is generally only indicated if one is considering surgery; in other words, your pain and neurological status is such that surgery is clinically indicated. Then, an MRI may be helpful for the surgeon. If surgery is not indicated based on clinical/symptoms, then it probably is unwise to get an MRI. They often show abnormalities that are simply 'red herrings' and often prompt people to proceed with surgery that really is not needed. Beware!

More discussions about herniation
References in periodicals archive ?
Extruded disc herniation was defined as 'in at least one plane, any one distance between the edges of the disc material beyond the disc space is greater than the distance between the edges of the base of the disc material'.11
The spinal computed tomography scan (CT scan) and magnetic resonance imaging (MRI) revealed the calcification within IVD associated with huge calcified disc herniation at T5/6 (black arrows in figure 1 and 2).
To evaluate the clinical results of percutaneous disc decompression (L'DISQ (TM)) applications in patients with lower radicular symptoms and/or dorsal pain due to thoracic disc herniation who did not respond to conservative methods.
Complications associated with ureteral herniation are uncommon, and many cases go unnoticed for years.
[3] Intervertebral disc herniation is the most common cause of lumbosacral radiculopathy in patients under the age of 50 years.
Concurrent herniation of the air sac or secondary rupture of the air sac as a result of increased pressure from the oviduct is likely, because the left abdominal air sac is located between the body wall and the oviduct.
Recurrent lumbar disc herniation recurrence after percutaneous endoscopic lumbar discectomy: A case report.
According to the MRI scans, median/paramedian disk herniation was present in 268 (97.1%) patients in the OD group and in 211 (86.8%) patients in the MD group.
For example, diabetic truncal radiculopathy can also present with unilateral abdominal wall herniation. The patient population consists of middle-aged or elderly diabetic men usually accompanied by a severe weight loss.
The total number of cases with single-level disc pathology was 80 (42 with bulging, and 38 with herniation).
It then stands to reason that patients over 40 will be more likely to have a disc herniation. Fortunately, the lumbar region of the spinal canal has some extra room to allow the nerves to move away from a ruptured disc.