Abstract
Reflex sympathetic dystrophy (RSD) is an infrequent cause of face and neck pain. Also known as chronic regional pain syndrome type I, RSD of the face is a classic case in which the clinician must think of the diagnosis to make it. The common denominator in all patients suffering from RSD of the face is trauma, which may take the following forms: actual injury to the soft tissues, dentition, or bones of the face; infection; cancer; arthritis; or insults to the central nervous system or cranial nerves. The hallmark of RSD of the face is burning pain. The pain is frequently associated with cutaneous or mucosal allodynia and does not follow the path of either the cranial or the peripheral nerves. Trigger areas, especially in the oral mucosa, are common, as are trophic skin and mucosal changes in the area affected by RSD. Sudomotor and vasomotor changes may also be identified, but these are often less obvious than in patients suffering from RSD of the extremities.
Keywords
reflex sympathetic dystrophy, atypical facial pain, facial trauma, chronic regional pain syndrome, stellate ganglion block, allodynia, temporal arteritis
ICD-10 CODE G90.59
The Clinical Syndrome
Reflex sympathetic dystrophy (RSD) is an infrequent cause of face and neck pain. Also known as chronic regional pain syndrome type I, RSD of the face is a classic case in which the clinician must think of the diagnosis to make it. Although the symptom complex in this disorder is relatively constant from patient to patient, and although RSD of the face and neck closely parallels its presentation in an upper or lower extremity, the diagnosis is often missed. As a result, extensive diagnostic and therapeutic procedures may be performed in an effort to palliate the patient’s facial pain. The common denominator in all patients suffering from RSD of the face is trauma ( Fig. 14.1 ), which may take the following forms: actual injury to the soft tissues, dentition, or bones of the face; infection; cancer; arthritis; or insults to the central nervous system or cranial nerves.
Signs and Symptoms
The hallmark of RSD of the face is burning pain. The pain is frequently associated with cutaneous or mucosal allodynia and does not follow the path of either the cranial or the peripheral nerves. Trigger areas, especially in the oral mucosa, are common, as are trophic skin and mucosal changes in the area affected by RSD ( Fig. 14.2 ). Sudomotor and vasomotor changes may also be identified, but these are often less obvious than in patients suffering from RSD of the extremities. Often, patients with RSD of the face have evidence of previous dental extractions performed in an effort to achieve pain relief. These patients also frequently experience significant sleep disturbance and depression.
Testing
Although no specific test exists for RSD, a presumptive diagnosis can be made if the patient experiences significant pain relief after stellate ganglion block with local anesthetic. Given the diverse nature of the tissue injury that can cause RSD of the face, however, the clinician must assiduously search for occult disease that may mimic or coexist with RSD (see “ Differential Diagnosis ”). All patients with a presumptive diagnosis of RSD of the face should undergo magnetic resonance imaging of the brain and, if significant occipital or nuchal symptoms are present, of the cervical spine. Screening laboratory tests consisting of a complete blood count, erythrocyte sedimentation rate, and automated blood chemistry should be performed to rule out infection or other inflammatory causes of tissue injury that may serve as a nidus for RSD.