Mechanisms and Manifestations
In simple words, when there is excessive pressure within the lower pharynx, the weakest portion of the pharyngeal wall balloons out, forming a diverticulum which may reach several centimetres in diameter.
More precisely, while traction and pulsion mechanisms have long been deemed the main factors promoting development of a Zenker's diverticulum, current consensus considers occlusive mechanisms to be most important: uncoordinated swallowing, impaired relaxation and spasm of the cricopharyngeus muscle lead to an increase in pressure within the distal pharynx, so that its wall herniates through the point of least resistance (variously known as Killian's triangle, Laimer's triangle, and the Killian-Laimer triangle). The result is an outpouching of the posterior pharyngeal wall, just above the oesophagus, specifically just above the cricopharyngeal muscle.
While it may be asymptomatic, Zenker diverticulum often causes clinical manifestations such as dysphagia (difficulty swallowing), and sense of a lump in the neck; moreover, it may fill up with food, causing regurgitation (reappearance of ingested food in the mouth), cough (as some food may be regurgitated into the airways), halitosis (smelly breath, as stagnant food is digested by microrganisms), potential infection of the pharyngeal areas due to food stuck, and involuntary gurgling noises when swallowing. It rarely, if ever, causes any pain.
Cervical webs are seen associated in 50% of patients with this condition.
Read more about this topic: Zenker's Diverticulum