Lateral pterygoid muscle

Lateral Pterygoid Muscle

The lateral pterygoid muscle is one of the muscles located in the temporomandibular joint (TMJ) region of the skull. It plays a crucial role in the movement of the jaw and is responsible for various functions such as opening the mouth, protruding the jaw, and moving it from side to side.

Anatomy

The lateral pterygoid muscle is a paired muscle located on both sides of the skull. It originates from two distinct heads: the upper head and the lower head.

The upper head of the lateral pterygoid muscle arises from the infratemporal surface of the greater wing of the sphenoid bone. It inserts into the articular disc of the TMJ and the capsule of the joint.

The lower head of the lateral pterygoid muscle originates from the lateral surface of the lateral pterygoid plate of the sphenoid bone. It inserts into the pterygoid fovea of the mandible.

Function

The lateral pterygoid muscle has several important functions in the movement of the jaw:

1. Opening the mouth: The contraction of the lateral pterygoid muscle helps in the initial opening of the mouth by pulling the condyle of the mandible forward and downward.

2. Protruding the jaw: The lateral pterygoid muscle is responsible for protruding the jaw, allowing for actions such as biting and chewing.

3. Side-to-side movement: The lateral pterygoid muscle plays a significant role in moving the jaw from side to side, enabling actions like grinding food.

Clinical Significance

The lateral pterygoid muscle is closely associated with temporomandibular joint disorders (TMD). Dysfunction or imbalance of this muscle can lead to various symptoms, including jaw pain, clicking or popping sounds during jaw movement, limited jaw mobility, and headaches.

Treatment for TMD often involves physical therapy, pain management, and in severe cases, surgical intervention. Understanding the anatomy and function of the lateral pterygoid muscle is crucial in diagnosing and managing TMD-related issues.

See Also

• Temporomandibular joint
• Muscles of mastication
• Temporomandibular joint disorder