13 Facial Pain
Because doctors can usually differentiate headache from other causes of facial pain, the differential diagnosis of headache is discussed in Chapter 17. Typically, by the time patients consult a physician for facial pain, they already have visited a dentist several times. This fact illustrates the diagnostic difficulty.
The most common causes of facial pain are dental and oral diseases, and TMJ dysfunction. Other causes of facial pain include eye disease (glaucoma); nose or sinus disease (sinusitis); vascular pain such as migraine and temporal arteritis; neurologic pain, such as trigeminal neuralgia (TGN); sphenopalatine neuralgia (SPN); glossopharyngeal neuralgia (GPN), herpes zoster, post-herpetic neuralgia, referred pain, rarely from angina pectoris and occasionally from muscle contraction headaches; and psychogenic pain, such as that seen with atypical facial pain, hysteria, and depression. Another means of classifying facial pain is by its components: neuropathic, myofascial, migrainous, or supraspinous.
Because pain is a symptom and cannot be seen or easily measured, the evaluation and diagnosis must depend on the patient’s description; therefore, historical details that the clinician elicits are important. A patient’s reaction to pain can be seen and may indicate the severity of the pain.
With chronic pain the initial symptoms may have been psychologically based, further complicating the diagnostic process. Depressed, anxious, or neurotic people often seek help for organic causes of facial pain more frequently than other people. In addition, chronic or recurrent episodes of facial pain can lead to depression and anxiety.
TGN is more common in patients older than 50 years. If facial pain occurs in a younger patient (less than age 40), TGN is less likely, and other conditions that can mimic tic douloureux should be considered. These include multiple sclerosis, acoustic neuroma, and trigeminal neuroma, especially if the upper division (pain in the forehead or eye) is involved or the symptoms are unilateral.
TMJ dysfunction is more common in female patients older than 40 years, particularly if they are edentulous or have worn posterior teeth or poorly fitting dentures, but it can accompany severe malocclusion or mandibular trauma at any age. Patients with rheumatoid arthritis appear to have a higher incidence of TMJ dysfunction.
Atypical facial pain is most common in women between ages 30 and 50; 60% of these patients have a similar family history. Such pain tends to occur in people with a history of high stress, drug addiction, low self-esteem, impotence or frigidity, marital or family conflicts, or prior episodes of anxiety or depression. The typical patient is an edentulous, haggard-looking, middle-aged woman. She may have a history of concomitant psychiatric illness as well.
The mnemonic PQRST is helpful in dealing with painful conditions. P represents precipitating or palliating factors; Q refers to the quality of the pain (sharp or stabbing, burning or stinging, aching, boring, or throbbing); R stands for radiation and original location of pain; S stands for severity (score of 1-10 or how the pain compares with prior painful experiences); and T stands for timing, including initial onset, duration, frequency, seasonal, daily, and whether nocturnal or diurnal.
The quality of dental pain is often severe, throbbing, and poorly localized. Excruciating, lancinating, stabbing, paroxysmal pain is characteristic of the trigeminal, sphenopalatine, and glossopharyngeal neuralgias. The pain of glaucoma is described as dull and frontally located. However, the pain of acute narrow-angle glaucoma can cause severe pain of abrupt onset. Myofascial pain is often described as deep, continuous, and producing a dull ache.
Pain is relatively uncommon in patients with chronic or subacute sinusitis; it is typically seen with episodes of acute sinusitis, which may be superimposed on subacute sinusitis. Sinusitis pain is usually dull and relatively constant; it may occasionally be described as throbbing. This pain is usually located over the affected sinus or behind the orbit. However, with sphenoid sinusitis, pain may present at the vertex of the head and may radiate to the neck and orbit. Sinusitis pain is usually unilateral but can be bilateral.
Neuralgia pains usually have a sudden onset. A typical attack may consist of two to three stabbing pains over 1 minute. Episodes may become more frequent with time, and several attacks may occur in a single day, with spontaneous remission for weeks or months. The pain may be recurrent, but it is usually paroxysmal and instantaneous. Although the actual pain may last only a few seconds and then disappear, some patients experience a gradual transition from lancinating pain to a vague ache or burning. TGN pains usually occur during the day, whereas glossopharyngeal pains often develop at night. Over time the episodes of TGN may become more frequent and may occur one or more times daily. These pains seldom awaken patients from sleep.
The pain of glaucoma may be precipitated by dark rooms. The timing is gradual in onset, although the pain of acute narrow-angle glaucoma can begin suddenly and may manifest as a dramatic emergency. The timing of the pain of sinusitis is gradual in onset and can last for days to weeks if not adequately treated.
Most causes of facial pain, including dental problems, TGN, sinusitis, glaucoma, and TMJ dysfunction, manifest as unilateral pain; occasionally, all can be bilateral or alternating. The pain of TGN is located over the course of one of the three divisions of the fifth cranial nerve. It is usually unilateral but is bilateral in 5% to 10% of patients. The bilateral attacks tend to be more common in certain families and possibly more common in women. TGN most often occurs along the distribution of the second (maxillary branch) or third (mandibular branch) division and seldom over the first division (ophthalmic branch). Most patients report that the pain is on the surface, not deep inside the head, as is more common with sphenopalatine ganglion neuralgia. Both the lancinating nature of neuralgia pain and the tendency to be remittent and associated with trigger areas distinguish it from the more chronic pain of sinus infection, dental abscesses, and glaucoma.
The anatomic distribution of the pain helps differentiate neuralgia from atypical facial pain, which is not confined to an anatomic distribution of any cranial or cervical nerve. The entire side of the head as well as the face, neck, or throat may be involved.
The pain of subacute glaucoma usually causes frontal headaches, whereas the pain of acute glaucoma is often described as pain in the eye or just behind the eye radiating to the head, ears, or teeth. The pain of sinusitis corresponds in location to the sinus involved. Patients with maxillary sinusitis usually complain of pain over the cheek or under the eye; the pain of frontal sinusitis is above the eyes or in the forehead; and the pain of ethmoid sinusitis is most often supraorbital and may occasionally radiate to the vertex of the head. Sphenoid sinusitis and ethmoid sinusitis seldom occur as isolated phenomena; they are usually associated with other forms of sinusitis.
The pain of TMJ arthritis or dysfunction is normally located in the TMJ area, although it may be referred to the ear or temples, thus simulating the pain of a tension headache. Any time a patient complains of pain in the ear and physical findings in the ear are normal, the physician should palpate over the TMJ, question the patient for other signs and symptoms of TMJ dysfunction, and consider other causes of referred otalgia. The pain of TMJ dysfunction may radiate to either the teeth or the ear.