The pterygoid processes of the sphenoid bone or processus pterygoideus ossis sphenoidalis in Latin are inferior bony extensions that descend perpendicularly from the junction of the great wings and the base of the sphenoid body. Each process consists of a broad lateral pterygoid plate and a narrow medial one.
The plates are separated from below by the angular pterygoid fissure that diverges from behind and articulates with the pyramidal process of the palatine bone. Both the tensor veli palatine and medial pterygoid muscles lie between the plates at the cuneiform pterygoid fossa. The root of the pterygoid process is thick, broad, and triangular in form. It creates the posterior wall of the pterygopalatine fossa and the anterior opening of the pterygoid canal piercing it. The pterygoid canal houses the greater petrosal nerve, the deep petrosal nerve, and the pterygoid canal artery and vein.
The lateral surface of the lateral plate forms the medial wall of the infratemporal fossa, where the lower part of the lateral pterygoid is attached. The medial deep head of the pterygoid however attaches to the medial surface, at the lateral wall of the pterygoid fossa. The upper part of the anterior border bounds the pterygomaxillary fissure posteriorly, and the lower part articulates with the palatine bone. The posterior border is free. Inferiorly, it bears the palatovaginal canal formed by the sphenoidal process of the palatine bone. This canal transmits pharyngeal branches of the maxillary artery and the pterygopalatine ganglion (pharyngeal nerve).
The lower end of the medial plate of the pterygoid process continues as the pterygoid hamulus, a hook-like projection that curves laterally and has the tendon of the tensor veli palatini wound up around it. The medial plate’s upper posterior border divides to form a small, shallow, canoe-shaped scaphoid fossa, where part of the veli palatine attaches to it.
Le Fort fractures are fractures involving the midface. It is the separation of all or a portion of the midface from the skull base. In order for that to happen, the pterygoid plates of the sphenoid bone need to be displaced. This diagnosis is confirmed radiographically.
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