The lateral pterygoid muscle is a small, yet powerful muscle located in the face and neck region. It is a part of the masticatory system, which is responsible for the movement of the mandible (jaw) during chewing and other facial movements.
Structure
The lateral pterygoid muscle is a flat, triangular muscle that originates from the infratemporal surface of the lateral pterygoid plate and the pterygoid fossa of the sphenoid bone. It has two heads: an upper head and a lower head. The upper head is longer and thicker, while the lower head is shorter and thinner.
The muscle fibers of the upper head run vertically, while those of the lower head run horizontally. Both heads converge and attach to the articular tubercle of the mandible, which is a bony protuberance on the lower jaw.
Location
The lateral pterygoid muscle is located in the infratemporal fossa, which is a shallow, triangular-shaped depression located below the temporal bone and behind the mandible. It is surrounded by other muscles and structures, including the medial pterygoid muscle, the masseter muscle, the temporalis muscle, and the lateral pterygoid plate.
Function
The main function of the lateral pterygoid muscle is to move the mandible. It can elevate the mandible, which allows the jaw to open, or protract the mandible, which allows the jaw to move forward. It can also help to stabilize the mandible during chewing and other facial movements.
In addition to its role in mandibular movement, the lateral pterygoid muscle also plays a role in respiration and speech. It can assist in the expansion of the rib cage during inhalation and in the production of certain sounds during speech.
Clinical Significance
Problems with the lateral pterygoid muscle can lead to a range of facial and oral problems. Dysfunction of the muscle can cause pain and discomfort in the jaw and face, difficulty chewing and swallowing, and problems with speech. It can also cause the mandible to deviate to one side or the other, leading to misalignment of the teeth.
Treatment for problems with the lateral pterygoid muscle may include physical therapy, medications, and/or surgery. In severe cases, the muscle may need to be surgically removed or relocated to restore normal function.
