• Origin

Superior head: Infratemporal surface and crest of the greater wing of the sphenoid bone.
Inferior head: Lateral surface of the lateral pterygoid plate of the sphenoid bone

• Insertion

Neck of the mandible (condyloid process),
Articular disc and capsule of the temporomandibular joint (TMJ)

• Agonist(s)

- Medial pterygoid (for side-to-side movements)
- Masseter (for specific mandibular movements)
- Temporalis (assists in some movements)

• Antagonist(s)

- Temporalis (posterior fibers)
- Masseter (for mandibular elevation and retraction)

• Function

Protracts the mandible (moves it forward),
Assists in opening the mouth by depressing the mandible,
Contributes to side-to-side (lateral) movements of the jaw, essential for chewing and grinding.

TRIGGER POINT(S)

• Location

Trigger points are located deep within the muscle, usually near the condyloid process of the mandible and around the TMJ.

Due to the muscle's depth, trigger points are best accessed intraorally by a trained professional.

• Pain Referral Pattern

Pain often refers to the TMJ area, manifesting as discomfort or aching around the jaw joint, and can extend to the ear, upper cheek, and possibly to the temple.

It may also mimic symptoms of ear pain or fullness and occasionally lead to headaches.

• Potential Causes

• Excessive chewing or bruxism (teeth grinding).
 

• TMJ dysfunction.
 

• Trauma to the jaw or face.
 

• Prolonged jaw clenching due to stress or poor posture.
 

• Dental misalignment or uneven bite.

• Prevention Tips

• Avoid clenching the jaw and practice relaxation techniques.
 

• Minimize excessive chewing or hard foods that stress the jaw.
 

• Use a mouthguard at night if bruxism is present.
 

• Perform gentle jaw stretches to maintain muscle flexibility.
 

• Seek dental consultation for bite correction if necessary.