The cricoid cartilage is a ring-shaped cartilage that fully encircles the trachea (windpipe) and forms the lowest part of the larynx (voice box), and it plays a critical, well-known role in emergency medicine through a technique called cricoid pressure, used during certain intubation procedures. This guide covers its anatomy, function, and clinical significance.
This is general information, not medical advice.
Anatomy and location
The cricoid cartilage sits below the larger thyroid cartilage (the structure that forms the visible “Adam’s apple”) and is unique among the laryngeal cartilages in one important way: it’s the only one that forms a complete ring fully encircling the airway, shaped somewhat like a signet ring, which is actually where its name comes from (“cricoid” derives from the Greek word for ring-shaped). It has a narrow front (anterior) arch and a broader back (posterior) lamina. It sits at the boundary between the larynx above and the trachea below, connected to the first ring of the trachea by the cricotracheal ligament, and to the thyroid cartilage above via the cricothyroid membrane, an important anatomical landmark for certain emergency airway procedures.
Function
As the only complete cartilaginous ring in the airway, the cricoid cartilage serves a critical structural role: it maintains the shape and patency (openness) of the airway at this level, providing a stable, rigid framework that keeps this part of the airway from collapsing, unlike the softer trachea below, which is supported by incomplete, C-shaped cartilage rings. It also serves as an attachment point for several important laryngeal muscles and ligaments involved in voice production and swallowing, and it articulates with both the thyroid cartilage above and the arytenoid cartilages, which are directly involved in vocal cord movement.
The clinical significance: cricoid pressure
This is likely the most well-known practical application of this specific anatomical structure. Cricoid pressure (sometimes called the Sellick maneuver) is a technique where a clinician applies firm downward pressure on the cricoid cartilage during certain emergency airway procedures, historically used during rapid sequence intubation to help compress the esophagus (which sits directly behind the cricoid cartilage) against the spine, theoretically reducing the risk of stomach contents being regurgitated and aspirated into the lungs during the procedure. It’s worth noting that the evidence supporting cricoid pressure’s effectiveness has become more debated in recent medical literature, and its use has become somewhat less routine and more individualized in current emergency medicine practice than it once was, though the cricoid cartilage’s anatomical relevance to airway management procedures generally remains well established.
Other clinical relevance
The cricothyroid membrane, located between the thyroid and cricoid cartilages, is the key landmark for an emergency procedure called cricothyrotomy, a life-saving airway access procedure performed when a patient cannot be intubated or ventilated through the mouth or nose in a true airway emergency. The cricoid cartilage’s position as a fixed, easily palpable landmark in the neck makes it a critical reference point for this and other airway-related emergency procedures.
Frequently asked questions
What makes the cricoid cartilage different from other laryngeal cartilages?
It’s the only cartilage in the larynx that forms a complete ring fully encircling the airway, giving it a unique structural role in keeping this part of the airway open and stable.
What is cricoid pressure used for?
It’s a technique applying downward pressure on the cricoid cartilage during certain emergency intubation procedures, historically intended to reduce the risk of stomach contents being aspirated into the lungs, though its routine use has become more debated and individualized in current practice.
What is the cricothyroid membrane?
The membrane located between the thyroid and cricoid cartilages, serving as the key anatomical landmark for cricothyrotomy, an emergency airway access procedure.
Can you feel your cricoid cartilage?
Yes, it can typically be felt in the front of the neck, just below the larger thyroid cartilage (Adam’s apple), as a firm, ring-like structure.
What connects the cricoid cartilage to the trachea?
The cricotracheal ligament connects the lower border of the cricoid cartilage to the first ring of the trachea below it.