Trigeminal Neuralgia: The Worst Head Pain

Anyone who has experienced toothaches, blocked sinuses, earaches, corneal scratches or migraine headaches knows that pain arising from any part of the head can be severe. Head pain is transmitted to the brain through the fifth of twelve pairs of cranial nerves at the base of the brain, named the trigeminal nerves. The worst head pain of all is the result of one or the other of these nerves misfiring, a condition known as trigeminal neuralgia, in which hundreds of episodes a day of lightning like spasms of pain on one side of the face are triggered by trivial touch or movement or by nothing identifiable. The pain is severe enough to bring sufferers to their knees and to cause more than a few to say that if it persisted they would have to commit suicide. The famous painting, The Scream, by Norwegian artist Edvard Munch, has been called a visual representation of the agony caused by trigeminal neuralgia.

Symptoms

Symptoms of trigeminal neuralgia are almost always one-sided. Spasms of facial pain are brief and explosive and described as stabbing, electrical, or like being stuck with an ice pick. Episodes can last for weeks or months, and then disappear not to return, or they may return in similar fashion, without warning, months or years later. Pain bouts may also become chronic and associated with other duller, longer lasting pain in the same area of the face. Because light touch and facial movements such as chewing and talking can trigger pain, patients avoid eating, lose weight, become depressed and socially withdrawn and look disheveled from avoiding skin care and shaving.

Why does it happen?

About 150,000 new cases of trigeminal neuralgia are diagnosed in the US every year, more often in women than men and usually over age 60. The ailment can appear in younger people, most often in conjunction with multiple sclerosis. As long ago as the eleventh century, an Arab physician, Jujani, suggested that a blood vessel in the head, near the nerve that served the face, caused spasmodic facial pain and anxiety, a prescient notion since one of the few risk factors for trigeminal neuralgia is high blood pressure. Chronic high blood pressure distorts and hardens arteries, and one of the most effective treatments of trigeminal neuralgia in modern times has been to pad the nerve, protecting it from the pounding of an overlying artery.

Bolstering Jujani’s theory, pathological examinations of trigeminal nerves have shown evidence of damage and repair to the sheaths surrounding individual nerve fibers, suggesting that pressure from a nearby artery or vein, causes intermittent, reversible damage. The association of trigeminal neuralgia with multiple sclerosis, an inflammatory disease which also causes myelin sheath damage, lends weight to the idea that stripping sensory nerve fibers of their myelin sheaths somehow causes them to be irritable and misfire. There is no specific test for trigeminal neuralgia, which can be diagnosed from the clinical history alone. However, sometimes CT and MRI scans are done to rule out tumors irritating the trigeminal nerve, or to look for evidence of demyelinating diseases like multiple sclerosis or other autoimmune problems. Spinal fluid analysis might be added a search for inflammatory or demyelinating marker proteins and cells.

Similar conditions

Other conditions may produce shooting head pains. One is glossopharyngeal neuralgia, coming from irritation of a different cranial nerve and causing pain deep in the throat and ear. It is much rarer than trigeminal neuralgia, but medical treatments are similar. Another is occipital neuralgia which comes from compression of a nerve in the upper neck, at the base of the skull. This painful condition is associated with poor posture, trauma or arthritic changes. Occipital neuralgia presents itself as stabbing or shooting pains, as well as duller aching pain and general headaches in the back and sides of the head, and at times behind the eyes. Temporomandibular joint problems (the joint that hinges the jaw to the skull) may also cause shooting pain in the side of the face, along with jaw pain and locking.

Treatments

The first effective treatment of trigeminal neuralgia was based on the concept of nerve cell irritability, with the use of drugs that treated seizures, first introduced in the mid-1900s. Though not perfect, these drugs continue to provide significant relief for the majority of trigeminal neuralgia sufferers. In addition, many attempts have been made to change the input of the trigeminal nerve to the brain physically by cutting it or injecting it with chemicals that deaden it. This treatment is called neuro-ablative surgery and the relief obtained is in direct proportion to the amount of numbness in the face caused by deliberately damaging the nerve. The more numbness, the better the pain relief. However, for some people, persistent facial numbness or unpleasant sensations are almost as intolerable as the pain, so numerous variations on such procedures have been tried. There are few controlled studies of outcome. Gamma knife surgery is the latest method. Symptoms recur within three years in 20-60% of patients, in inverse proportion to the amount of numbness produced by this deliberate nerve damage.

Microvascular decompression surgery (MVD), as mentioned above, is the most effective surgical procedure for trigeminal neuralgia. It involves opening the skull and placing a Teflon felt pad between the trigeminal nerve and the blood vessel that lies atop it, just where the nerve enters the brain stem. In experienced hands MVD produces immediate pain relief in over 90% of cases, with relief sustained for a decade or more in over 2/3 of them. Though many patients would rather try this or other surgical procedures than be dependent on anticonvulsant drugs, they must carefully weigh the risks, which are those of general anesthesia and of opening the cranial cavity, infection and damage to delicate neural structures chief among the possibilities. Procedures such as these should be done in centers where experience levels of all involved are demonstrable.

All the pains we suffer are reminders that our exquisitely complicated pain networks exist to guard the body, particularly the head and the brain within, against damage from the environment. Like every other part of the body, the pain systems can go awry, making life very difficult, but this is nature’s trade-off since life without pain is more dangerous. In conditions like trigeminal neuralgia we are left to try to understand the cause and to intervene as best we can without causing harm.

Posted by medical plaintalk

Physician turned medical writer.

The Headaches that Predict Catastrophe

One of the most treacherous problems a busy emergency room physician faces is headache. “Headache” is a very common symptom, different from focal head pains attributable to sinus, eye or ear problems. While very painful and sometimes associated with nausea and vomiting, the vast majority of headaches, even if frequent and debilitating, are benign. They do not signify underlying illnesses or impending danger. But the emergency physician cannot afford to be wrong about the rare headache that predicts oncoming catastrophe and provides a chance to intervene.

Two broad categories

Catastrophic headaches fall into two broad categories. The first category includes “space-occupying lesions” such as tumors, hemorrhages, abscesses, and hydrocephalus (known commonly as “water on the brain”). The second category involves infectious and autoimmune problems that produce inflammation, triggering pain receptors in the membranes surrounding the brain and its blood vessels. Catastrophes avoided by successful interventions in both categories include death, permanent brain damage and blindness.

Tumors and abscesses

The most common fear about a bad headache is that it is caused by a brain tumor, but tumors usually produce other symptoms, involving speech, thinking, coordination or vision before they produce headache. Since the brain tissue itself has no pain receptors, tumors cause headache when they distort surrounding membranes or blood vessels, which have pain receptors. Tumor-related headaches worsen with positions and activities that normally cause the pressure in the veins in the head to rise – coughing, sneezing, lying down, straining at a bowel movement or lifting something heavy. As tumor size and pressure increase, nausea and vomiting appear. Occasionally, brain abscesses – pockets of infection surrounded by capsules -may mimic tumors. They usually come from blood infections seeding bacterial or fungal organisms into the brain.

Hemorrhages in the brain

Brain hemorrhages occupy space and increase pressure in the head. Deep small blood vessels, damaged by high blood pressure or arteriosclerosis, are usually the culprits. While these intracerebral hemorrhages can cause sudden headache, stroke-like symptoms such as paralysis, confusion, trouble speaking and loss of consciousness occur first or soon after the onset of headache.

Hemorrhages outside the brain, but inside the head

Headaches are also a symptom of epidural and subdural hematomas – collections of blood that accumulate over the surface of the brain hours to weeks after some closed head injuries (meaning no skull fracture). The history of injury, even seemingly trivial injury in an elderly patient, is crucial to correct evaluation of these headaches and there may be no other accompanying neurological symptoms. A head blow in the temple, where the skull is the thinnest is a common history. Young children and older adults are more susceptible to epidural hematomas (located between the inner skull and the the dural membrane over the brain) than those in between those age groups. Both epidural and subdural (between the dural membrane and the surface of the brain) collections of blood usually require surgical removal, sometimes as an emergency if symptoms such as change in level consciousness appear. Actor Liam Neeson’s wife Natasha Richardson did not survive an epidural hematoma incurred in a skiing related fall in 2009.

The “sentinel headache” of the aneurysm

Bleeding from brain aneurysms – weak spots at branch points of arteries – can be immediately catastrophic, even causing sudden death. But a tiny, warning leak before an aneurysm actually ruptures may cause a “sentinel headache” which allows time for life-saving surgical repair to prevent the oncoming, big rupture which typically occurs sometime in the next 10 days. A sentinel headache is sudden and severe pain involving all or part of the head, It is sometimes described like a “thunderclap.” As the little warning squirt of blood dissipates in the spinal fluid around the base of the brain, the headache dulls but a peculiar, longer-lasting pain may appear in the middle of the upper back, usually worsened with movement and probably indicating irritation from blood in the spinal fluid around the spinal cord. Diagnosis involves brain imaging with dye to study the arteries, and possibly a spinal tap to make certain bleeding has occurred. Unruptured cerebral artery aneurysms are found incidentally in 2% of autopsies so the problem is not rare.

Hydrocephalus

Hydrocephalus is a rare cause of headache, but one that should never be overlooked. The rise in pressure in the head comes from spinal fluid being trapped in the ventricles, hollow structures in the center of the brain where spinal fluid is made. Normally the spinal fluid circulates out of the ventricles via a very small channel, and bathes the surface of the brain and spinal cord before being absorbed into special veins at the top of the head. If flow is blocked, the ventricles begin to enlarge putting pressure on the surrounding brain. Most times, the onset of hydrocephalus is gradual, with headache, nausea, vomiting and balance problems gradually increasing. Unrecognized and untreated, obstructed spinal fluid flow leads to lethargy, coma and death, within 24 hours if the obstruction is sudden. Causes of obstruction include congenital anatomical abnormalities, tumors blocking the ventricular outflow tracts, scarring of these passages by inflammation from past meningitis or bleeding. Hydrocephalus most often requires surgical intervention to either remove the obstruction or to place a shunt around it, allowing cerebrospinal fluid to escape from the ventricles.

Headache from infection

Headache producing infections mainly involve the meninges, the membranes covering the brain and the spinal cord and are caused by viruses, bacteria or fungi. Viral and bacterial meningitis both cause severe headache, neck pain and rigidity and photophobia – inability to tolerate bright light. Movements of head and trunk and even eye movements are painful. Someone suffering from bacterial meningitis has a high fever, looks extremely ill and deteriorates rapidly. Identification of the infection type requires spinal fluid, obtained via spinal tap – insertion of a large needle into the spinal canal in the low back. Antibiotics are lifesaving. Viral meningitis, though painful, is less dramatic, and gets better on its own. Fungal meningitis is rare and much slower and less dramatic in its presentation than bacterial meningitis. It most often occurs in people who have impaired immune systems and requires prolonged treatment with antifungal drugs.

Non-infectious inflammatory headache: temporal arteritis

Headache from a non-infectious inflammatory condition called temporal arteritis usually presents itself in the seventh or eighth decade of life as a constant, often one-sided pain. Other symptoms that provide clues to this diagnosis are pain in the jaw muscle, especially with chewing, and tenderness of the artery just under the skin of the temple – the origin of the name for auto-immune inflammation that affects the arteries that supply the skull and brain with blood and can cause blindness and strokes. Diagnosis is confirmed when a blood test called ESR (erythrocyte sedimentation rate) is elevated and a temporal artery biopsy shows characteristic inflammatory cells in the artery wall. Treatment with steroids like prednisone, undertaken soon enough, prevents blindness and takes the headache away, but must be continued for many months.

A very useful question

One of the most useful questions an emergency room physician, or any other professional evaluating a headache complaint can ask the patient is “How worried are you about this headache?” People know themselves and have an innate sense about the nature of their symptoms. They will very often know the difference between a catastrophic headache and all the others.

Posted by medical plaintalk

Physician turned medical writer.

Morning Foot Pain: Plantar Fasciitis

“.as we know, there are known knowns; there are things we know we know. We also know there are known unknowns; that is to say we know there are some things we do not know. But there are also unknown unknowns—the ones we don’t know we don’t know.” Donald Rumsfeld former US Secretary of Defense

In medicine, what we “know” changes regularly as long as curiosity keeps opening doors. For many decades, the complaint of pain in the bottom of the foot, just in front of the heel bone and always worse with the first few steps of the morning or after prolonged periods of inactivity, fell into the “known known” category. Doctors and physical therapists confidently made diagnoses of plantar fasciitis, certain there was inflammation in the plantar fascia, the band of tough fibrous tissue that spans the bottom of the foot. The condition was common, especially in runners, in people who spend a lot of time standing on hard surfaces and in post-menopausal women. Most of the time it resolved but there were enough prolonged and vexing cases that did not get better with anti-inflammatory medications and rest that some practitioners began to suspect that plantar fasciitis was a “known unknown” – maybe the cause was not so simple as the inflammation that they postulated. After all, no one had actually looked at the troublesome tissue under a microscope before.

Plantar fascia gets an inspection

In 2003, a Philadelphia podiatrist and pathologist, Harvey Lemont, took microscopic samples of the plantar fascia from patients undergoing surgical release of their presumably inflamed connective tissue. In all 50 samples he found no evidence of inflammation. But the tissue was not normal. The collagen structure was disorganized and degenerated, as if it had been deprived of sufficient blood flow. Some samples contained crystals from prior cortisone injections, common treatment for plantar fasciitis, but by 2000 known to carry significant risk of causing the plantar fascia to separate from the heel bone. Degeneration of plantar fascial structure, a previously unknown unknown, was discovered, and that prompted a change in the name plantar fasciitis to plantar fasciosis, a term which indicates chronic structural disruption but not inflammation.

Lack of inflammation prompts new thinking

Lack of inflammation in Dr. Lemont’s pathologic examinations explained the failure of conventional treatment many cases of plantar fasciitis. And his work raised significant questions about the cause of the problem. Why does the plantar fascia begin to degenerate? What exactly hurts? Is it the bone where the connective tissue attaches? Is it the connective tissue itself? Study of the feet of non-shoe wearing cultures in which our most common foot problems are practically non-existent, and more attention to foot, leg and gait biomechanics began to yield some different ideas, not only about the heel pain syndrome, but about bunions and hammertoes.

Are shoes the problem?

When we are babies and young children, our feet are widest at the tips of the toes. By the time we wear conventional shoes for decades, with shallow, narrow and tapered toe boxes and elevated heels (even running shoes have a 1-1.5” heel elevation), the big toe begins to curve toward its mates, which begin to curl under. The muscle that normally pulls the big toe away from the other toes is pulled inward and weakens because of inactivity. What does this have to do with the plantar fascia? The big toe muscle runs from heel to toe on the foot’s inside edge, right over the artery near the heel that supplies blood to the plantar fascia. Pulling it inward narrows the artery and decreases blood flow to the plantar fascia. It is possible that morning heel pain is ischemic pain, from lack of sufficient blood flow while the foot is dropped down during sleep. Gradual Improvement in the pain with walking may reflect better blood flow with activity, but over time insufficient blood flow takes a toll on the integrity of the tissue in the plantar fascia, adding pain from stressed attachment to the heel bone.

Wimpy foot muscles

For many years people with plantar fasciitis were told they had collapsed arches and flat feet. Or high arches and no flexibility. Or that they pronated – walking on the inside of their feet. Or supinated, walking on the outside of their feet. The treatment was external support with rigid orthotics. But feet are very individual in their structure, and there is little solid evidence that arch height causes problems. Much more evidence implicates weakness at the ends of the arch – the toes and the heels, which bear the weight of the body and are supported by muscles in the feet and in the lower legs.

A shift in treatment plans

Treatment of the heel pain syndrome is shifting to restoration of strength and flexibility in the foot. The plantar fascia functions as a windlass, a pulley that adds to the arch strength when the foot lifts at the heel and bends at the big toe joint to propel the body forward. The goal of therapy is not to stretch that windlass, but to realign the big toe and strengthen the not only the foot muscles that flex the toes and the sole, but also the muscles of the lower leg, the knee and the hip. The toes are coaxed to flatten out and spread by stretching the top of the foot and the front of the ankle and wearing toe spacers. (Useful resource below.)

In the acute phase of plantar heel pain, some external support of the foot under the arch often helps, as does a boot that keeps the foot from dropping down in bed at night. But these aids are temporary while the work of regaining foot strength and flexibility gets under way. It can be difficult to transition from elevated heels to flat shoes, and that process is almost like training for a new physical activity – short bouts at first, gradually increasing over time.

Improvement takes patience, persistence and consistency. All footwear needs to change to shoes with wide, deep toes boxes, flexible soles at the forefoot, and no elevation between heel and toe. Perhaps we will find more unknown unknowns and a way to combine healthy feet with fashionable shoes, but at the moment, the known knowns suggest that changing fashion norms to align them with natural foot function is more likely to be successful.

Resources:

https://naturalfootgear.com

Foot Conditions

Posted by medical plaintalk

Physician turned medical writer.

Over the Counter Pain Relief

Pain stayed so long, I said to him today

“I will not have you with me any more.”
I stamped my foot and said, “Be on your way,”
And paused there,
Startled at the look he wore.
“I, who have been your friend,” he said to me.
“I, who have been your teacher,
All you know of understanding love,
Of sympathy and patience I have taught you.
Shall I go?”

Author unknown

Pain is a friendly messenger, carrying news from the frontiers of the body to the command center of the brain. Like the messages traveling across telephone wires, pain is just a series of electrical impulses traveling up nerves. The brain sorts the electrical impulses and presents them to you, the conscious mind inside, as a coherent story about what’s going on down below. Sometimes the message triggers an immediate reflex action, like pulling a hand away from a hot stove, even before your mind grasps the problem.

How is pain relieved?

Relief from pain depends on stopping the electrical impulses carrying the pain message or on altering the way the brain puts the message together. Every drug or procedure used in pain treatment works on either the simple electrical message, or on its complex interpretation by the brain. Ultimate relief comes when the conscious mind disappears into sleep, which is of course the great achievement of general anesthesia. Consciousness is the barrier to complete relief of severe pain.

Most pain, however, is not the severe unremitting variety that requires treading the fine line between consciousness and oblivion. Most pain comes in an acute form that gets us to the doctor for treatment of a sudden illness, or in a chronic form related to our heads or our skeletons. Thousands of years ago Cicero made the distinction: “All pain is either severe or slight; if slight, it is easily endured; if severe, it will without doubt be brief.”

Willow bark – the first pain medicine

Time and chemistry have given us surgery, anesthetics, antibiotics and narcotics – life-savers for diseases heralded by severe pain. They have also given us lesser drugs for lesser pains, a long process beginning in the 5th century BC when Hippocrates recommended chewing the bark of the willow tree to relieve pain and reduce fever. A long line of chemical derivatives of the willow bark’s salicilin culminated in a stable powder patented and marketed in 1899 as aspirin, the world’s first synthetic drug. Aspirin launched the world’s pharmaceutical industries.

Anti-inflammation and pain

Inflammation causes pain and the purpose of the pain is to get you to attend to whatever is causing the inflammation. Pain relief from aspirin is best understood in terms of its anti-inflammatory effects, but the drug has multiple other biochemical properties, many still being discovered. One effect, on an enzyme involved in the production of chemicals that produce inflammation, led to the development of ibuprofen and its cousin naproxen. These newer drugs, non-steroidal anti-inflammatory drugs (NSAIDS), are mainstays in the treatment of the aches and pains of daily life. Anti-inflammatory steroids like prednisone are far more potent and used only when their risks are balanced by the seriousness of the problem under treatment.

Tylenol is not an anti-inflammatory drug

Tylenol, or acetaminophen, is commonly thought to be just like aspirin, but it is chemically unrelated, has no anti-inflammatory effects, produces no gastric upset and doesn’t affect blood clotting. It reduces fever by a direct action on the brain, but no one knows how it reduces pain. The pain-relieving properties of aspirin and the NSAIDS, apart from their anti-inflammatory effects, are also poorly understood. It is possible that they decrease pain perception in the mind, but if so, no one understands how. They are most effective after an acute injury, after simple surgical procedures, or with infrequent headaches (relief here is also of unknown mechanism).

Frequent analgesic use can increase pain problems

But what about pain of chronic conditions like osteoarthritis and frequent “tension” headaches, in which inflammation plays a lesser role? Much arthritic pain is from tightness and muscle imbalance. Gradual activity warms up joints and removes some of the discomfort. Exercise, heat, ice, massage, weight loss, stretching, Pilates, and yoga help minimize drug use in these chronic conditions. Frequent use of analgesics for headaches (more than once a week) actually lowers the threshold for headache triggers (like lack of sleep, alcohol, lack of exercise, stress, etc.) and for pain perception, and often leads to a cycle of increasing drug use producing increasing numbers of headaches. This phenomenon is known as rebound headache and it highlights the importance of other methods of headache prevention and relief (adequate sleep, stress management, attention to diet and exercise, etc.).

Selling pain relief like candy

Since 1915, when aspirin became available without a doctor’s prescription, the sale of over-the-counter (OTC) pain relief has achieved the heights late Merck chief Henry Gadsden aspired to when he wished aloud 30 years ago that he could sell drugs to healthy people just like Wrigley’s sells candy and gum. These days, OTC pain medicines are so readily available that they seem as harmless as the candy next to them on the shelf.

Side effects

Unlike candy, OTC pain relievers have to be processed by the liver and kidneys. Chronic use can produce liver and kidney impairment, even failure of these organs. Chronic analgesic use damages hearing. Aspirin and other NSAIDS may erode the stomach lining; all but Tylenol impair blood clotting. Recent statistical studies resulted in withdrawal of two newer NSAIDS from the market because people taking them had more heart attacks than those on placebos. The problem also appears in statistical analysis of those on high doses of the older NSAIDS.

Don’t kill the messenger – heed it

Because no drugs are risk-free and pain is just messenger telling you about a problem, try to reserve the pill option for pain that interferes with sleep or truly inhibits you from carrying out the activities that are important to you. Attend to the causes of the message in as many non-pharmaceutical ways as possible. And remember that an analgesic “virgin” or infrequent user gets more out of a painkiller than an analgesic veteran.

Posted by medical plaintalk

Physician turned medical writer.

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