Brachial neuritis is an acute condition that tends to affect younger individuals with a slight male predominance. Patients report excruciating shoulder, back, or arm pain followed by weakness of the arm or shoulder girdle. In a third of cases, it is bilateral. The cause is idiopathic, but cases have been reported following immunizations or viral infections. On examination, the patient has weakness in various distributions of the brachial plexus. The upper trunk is the preferred site of involvement, affecting strength of proximal arm and shoulder musculature. The anterior interosseous nerve is also affected preferentially, causing inability to form a pincer with the index finger and thumb. Sensory abnormalities are found but are not as profound as the motor dysfunction. Reflexes are diminished in the affected limb.
The differential diagnosis includes multiple cervical radiculopathies, Pancoast tumors, and neoplastic or inflammatory infiltration of the plexus. The diagnosis is usually clear, since a history of pain followed by weakness that plateaus in a week or two makes other diagnoses unlikely. A chest x-ray should be performed to look for mass lesions involving the brachial plexus. CSF analysis is required if there is a suspicion of other etiologies. Spine imaging and EMG may be performed outside the ED setting.
The management of brachial plexitis is conservative, and no therapies have been shown to affect the course of the illness. The prognosis is good, with most patients experiencing full recovery in months. If careful follow-up with a neurologist can be arranged and other causes or symptoms are excluded, admission to the hospital is elective.
Lumbarplexopathy, or diabetic amyotrophy, occurs in diabetic patients and presents with back pain followed by weakness. Patients report the acute onset of ipsilateral back pain, followed within days by progressive leg weakness. Sensory findings are absent. The examination reveals decreased leg power in a variety of patterns reflecting impairment of plexus function with relatively symmetric sensation. There may be muscle wasting in affected limbs in long-standing disease. Deep tendon reflexes may be diminished on the affected side. Bowel and bladder functions are not affected.
Laboratory studies are generally not helpful in the emergency setting. In the ED, routine plain films of the lumbar spine are useful to screen for spine compression from degenerative or neoplastic disease, and MRI is usually ultimately needed. The differential diagnosis also includes the cauda equina and conus medullaris syndromes and compression from arteriovenous malformations. CT scanning of the abdomen is useful to rule out aortic aneurysm and psoas muscle masses, which also lead to asymmetric lower extremity weakness. Patients with acute weakness from lumbar plexopathy should be admitted to the hospital for testing and rehabilitation to definitely determine the cause of weakness.
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Deal With Your Pain, Lead A Wonderful Life An Live Like A 'Normal' Person. Before I really start telling you anything about me or finding out anything about you, I want you to know that I sympathize with you. Not only is it one of the most painful experiences to have backpain. Not only is it the number one excuse for employees not coming into work. But perhaps just as significantly, it is something that I suffered from for years.