(See also Overview of Esophageal and Swallowing Disorders Overview of Esophageal and Swallowing Disorders The swallowing apparatus consists of the pharynx, upper esophageal (cricopharyngeal) sphincter, the body of the esophagus, and the lower esophageal sphincter (LES). The upper third of the esophagus... read more .)
Primary esophageal causes of dysmotility include
Systemic disorders causing esophageal dysmotility include
Many generalized disorders of neuromuscular function (eg, myasthenia gravis Myasthenia Gravis Myasthenia gravis is characterized by episodic muscle weakness and easy fatigability caused by autoantibody- and cell-mediated destruction of acetylcholine receptors. It is more common among... read more , amyotrophic lateral sclerosis Amyotrophic Lateral Sclerosis (ALS) and Other Motor Neuron Diseases (MNDs) Amyotrophic lateral sclerosis and other motor neuron diseases are characterized by steady, relentless, progressive degeneration of corticospinal tracts, anterior horn cells, bulbar motor nuclei... read more , stroke Overview of Stroke Strokes are a heterogeneous group of disorders involving sudden, focal interruption of cerebral blood flow that causes neurologic deficit. Strokes can be Ischemic (80%), typically resulting... read more 
, Parkinson disease Parkinson Disease Parkinson disease is a slowly progressive, degenerative disorder characterized by resting tremor, stiffness (rigidity), slow and decreased movement (bradykinesia), and eventually gait and/or... read more ) can affect swallowing but are not typically classified as esophageal motility disorders because they largely cause oropharyngeal dysphagia and not esophageal dysphagia.
Symptoms of esophageal motility disorders depend on the cause but typically include difficulty swallowing (dysphagia), chest pain, and/or heartburn.
Evaluation of esophageal motility disorders depends on the patient's presenting symptoms and may include upper gastrointestinal endoscopy Endoscopy Flexible endoscopes equipped with video cameras can be used to view the upper gastrointestinal tract from pharynx to proximal duodenum and the lower gastrointestinal tract from anus to cecum... read more 
, barium swallow X-Ray and Other Imaging Contrast Studies of the Gastrointestinal Tract X-ray and other imaging contrast studies visualize the entire gastrointestinal tract from pharynx to rectum and are most useful for detecting mass lesions and structural abnormalities (eg, tumors... read more 
, esophageal manometry Esophageal Manometry Manometry is measurement of pressure within various parts of the gastrointestinal tract. Manometry is done by passing a catheter containing solid-state or liquid-filled pressure transducers... read more , acid- and reflux-related tests Ambulatory pH Monitoring Ambulatory 24-hour esophageal pH monitoring with or without intraluminal impedance testing is currently the most common test for quantifying gastroesophageal reflux (see the American College... read more , and/or impedance planimetry Impedance Planimetry (See also Manometry.) Impedance planimetry provides real-time assessment of luminal distensibility and geometric changes in response to applied pressure in various parts of the gastrointestinal... read more 
. Impedance planimetry is a newer technology that simultaneously measures the area across the inside of the esophagus and the pressure inside in the lumen. This procedure allows measurements of esophageal distensibility.
