What is the difference between hiatal hernia, gerd, and achalasia?

HH, GERD, achalasia: Simplistically, a sliding hiatal hernia is a common upward bulge of stomach (with acid) thru the diaphragmatic hiatus (hole in diaphragm thru which esophagus & stomach connect). Gerd is physical movement of stomach contents into the esophagus, often associated with esophageal inflammation that can progress to esophageal cancer. Achalasia is motility disorder of esophagus and its lower sphincter.

Se. Below: Herd is a symptom of hiatal hernia achalasia a a nesophogeal motility disorder when part of your stomach is in your chest the sphincter of the end of the esophagus dosent work as well to close off the esophagus-.

Big difference: Hiatal hernia is when the stomach goes up in to the chest because the hole in the diaphragm for the the esophagus stretches out. Gerd is abnormal reflux of stomach contents into the esophagus typically causing heartburn and regurgitation. Achalasia is when the esophagus doesn't work to propel food through the esophagus and in to the stomach.

?: Hiatal hernia is a hernia at the esophageal hiatus through the diaphragm. Gerd is acid reflux from the stomach into the esophagus . Achalasia is hypertrophy/ stricture at the distal esophagus. Gerd can be associated with both hiatal hernia and achalasia but more so with hiatal hernia.

Big difference: Hiatal hernia is an anatomical problem, gerd is a functional problem with the valve between the stomach and esophagus being "too loose", and achalasia is a problem whereby the esophagus doesn't function at all due to loss of nerve function. The normal valve between the esophagus and stomach then becomes stiff, making swallowing food progressively more difficult.