Where is the lateral pterygoid located?
Where is the lateral pterygoid located?
infratemporal fossa
Lateral pterygoid is a two-headed, fan-shaped muscle located in the infratemporal fossa of the skull. It is one of the four masticatory muscles, along with the medial pterygoid, temporalis and masseter muscles. All these muscles act upon the temporomandibular joint (TMJ) to enable chewing (mastication) and biting.
What movement does the lateral pterygoid muscle perform?
The Lateral pterygoid muscle is active during mastication and during mandibular movements such as protrusion (forward movement of the mandible), abduction (depression of the mandible), mediotrusion (movement of the mandibular condyle towards the midline), and particularly during speaking, singing, and clenching.
What is the place of attachment of the lateral pterygoid muscle?
| Lateral pterygoid muscle | |
|---|---|
| Origin | Superior head: infratemporal surface of sphenoid bone. Inferior head: lateral pterygoid plate |
| Insertion | Superior head: anterior side of the condyle. Inferior head: pterygoid fovea |
| Artery | Pterygoid branches of maxillary artery |
| Nerve | Lateral pterygoid nerve from the mandibular nerve |
Why is the lateral pterygoid called the peripheral heart?
These communications are important for spread of infections and for collateral circulation. The pterygoid muscles and other muscles of mastication pump the blood from this plexus and are considered a “peripheral heart”. Chewing or yawning increases venous return.
Can you palpate the lateral pterygoid?
The lateral pterygoid muscle is inevitably quite tender in most individuals with TMJ issues or bruxism. To palpate, place the index finger inside the mouth. Apply pressure in a cranial direction just underneath the zygomatic arch.
Which muscles are responsible for right lateral deviation of the mandible?
Muscles
| Muscles | Actions |
|---|---|
| Lateral pterygoid | Protracts mandible, depresses chin, lateral deviation of mandible |
| Medial pterygoid | Works with masseter to elevate mandible, aids in protrusion, |
| Digastric Stylohyoid Mylohyoid Geniohyoid | Depresses the mandible against resistance when infrahyoid muscles stabilize or depress hyoid bone |
What muscles do lateral deviation of the mandible?
How do soleus muscles act as peripheral hearts?
Together, the calf’s muscles and deep vein system form a complex array of valves and pumps, often referred to as the “peripheral heart,” that functions to push blood upward from the feet against gravity.
Which muscle is called peripheral heart and why?
Also, in upright posture, the soleus is responsible for pumping venous blood back into the heart from the periphery, and is often called the skeletal-muscle pump, peripheral heart or the sural (tricipital) pump. Soleus muscles have a higher proportion of slow muscle fibers than many other muscles.
Is the lateral pterygoid part of the superior head?
Lateral pterygoid muscle. Superior head: infratemporal fossa. Superior head: anterior side of the condyle. The lateral pterygoid or external pterygoid is a muscle of mastication with two heads. It lies superiorly to the medial pterygoid .
Is the temporalis tendon part of the pterygoid muscle?
Besides the lateral pterygoid muscle, the masticator space also contains the temporalis tendon, masseter and medial pterygoid muscles and the pterygoid venous plexus, along with several structures anatomically related to the lateral pterygoid muscle.
Where does the insertion of the medial pterygoid take place?
The insertion joins the masseter muscle to form a common tendinous sling which allows the medial pterygoid and masseter to be powerful elevators of the jaw. Medial pterygoid is innervated by nerve to medial pterygoid (a branch of the mandibular nerve), which also innervates tensor tympani and tensor veli palatini.
When do you pronounce La, the pterygoid muscle opens your mouth?
The mnemonic “La” and “Me” is useful to quickly recall the functions of the pterygoid muscles at any time. When you pronounce “La” – your jaw is now open, so the lateral pterygoid muscle opens the mouth.