lateral pterygoid

Examples of lateral pterygoid in the following topics:

• Chewing Muscles

  • Lateral Pterygoid - The lateral pterygoid muscle has a triangular shape with two head, superior and inferior.
  • Actions - Together, the lateral pterygoids protract the jaw, working independently to produce lateral movement.
  • It is located inferior to the lateral pterygoid.
  • Produced by the lateral pterygoid, assisted by the digastric, mylohyoid and geniohyoid muscles found in the neck.
  • Arrows indicate the location of the lateral pterygoid, highlighted with the medial pterygoid in orange.

• Dislocated Mandible

  • For the mouth to close it requires the following muscles: the masseter, temporalis, and medial pterygoid muscle.
  • For the jaw to open it requires the lateral pterygoid muscle.
  • There are four different positions of jaw dislocation: posterior, anterior, superior, and lateral.
  • The muscles that are affected during anterior jaw dislocation are the masseter and temporalis, which pull up on the mandible, and the lateral pterygoid, which relaxes the mandibular condyle.
  • Differentiate among the 4 types of jaw dislocation: posterior, anterior, superior, and lateral

• Trigeminal (V) Nerve

  • The motor component of the mandibular division (V3) of the trigeminal nerve controls the movement of eight muscles, including the four muscles of mastication: the masseter, the temporal, and the medial and lateral pterygoids.

• Cranial Bones

  • The temporal bones are situated at the base and sides of the skull, lateral to the temporal lobes of the brain.
  • The sphenoid bone is divided into several parts: the body of the bone, two greater wings, two lesser wings, and the pterygoid processes.
  • The lesser wings project laterally and form the floor of the anterior cranial fossa and the superior orbital fissure through which several key optical nerves pass.

• Hemispheric Lateralization

  • But although measurable lateral dominance occurs, most functions are present in both hemispheres.
  • While many functions are lateralized, this is only a tendency.
  • While language production is left-lateralized in up to 90% of right-handed subjects, it is more bilateral or even right-lateralized in approximately 50% of left-handers.
  • The evolutionary advantage of lateralization comes from the capacity to perform separate parallel tasks in each hemisphere of the brain.
  • In a 2011 study published in the journal of Brain Behavioral Research, lateralization of a few specific functions as opposed to overall brain lateralization was correlated with parallel tasks efficiency.

• Ventricles

  • The cavities of the cerebral hemispheres are called lateral ventricles or first and second ventricles.
  • CSF flows from the lateral ventricles via the foramina of Monro into the third ventricle, and then into the fourth ventricle via the cerebral aqueduct in the brainstem.
  • This means they can be easily blocked, causing high pressure in the lateral ventricles.
  • As the future brain stem aspect of the primitive neural tube develops, the neural canal expands dorsally and laterally, creating the fourth ventricle.  
  • Lateral and anterior views of the brain ventricles, including the third and fourth ventricle, lateral ventricles, interventricular foramen, cerebral aqueduct, and central canal.

• Abducens (VI) Nerve

  • The abducens nerve (cranial nerve VI) controls the lateral movement of the eye through innervation of the lateral rectus muscle.
  • The abducens nerve (cranial nerve VI) is a somatic efferent nerve that, in humans, controls the movement of a single muscle: the lateral rectus muscle of the eye that moves the eye horizontally.
  • It then enters the orbit through the superior orbital fissure and innervates the lateral rectus muscle of the eye.

• Muscles that Cause Movement at the Hip Joint

  • The muscles of the lateral rotator group are deeply located and as the name suggests, act to laterally rotate the thigh at the hip.
  • Actions - Lateral rotation and abduction of the thigh at the hip.
  • Actions - Lateral rotation and abduction of the thigh at the hip.
  • Actions - Lateral rotation and abduction of the thigh at the hip.
  • Actions: Extends and laterally rotates at the hip.

• Carpals, Metacarpals, and Phalanges (The Hand)

  • The carpals are often split into two rows, the proximal row containing the scaphoid, lunate, triquetrum, and pisiform, moving lateral to medial.
  • The distal row contains the trapezium, trapezoid, capitate, and hamate, moving lateral to medial.
  • They are numbered moving lateral to medial, and start with the thumb, which is metacarpal I, and end with metacarpal V, the little finger.
  • Each metacarpal consists of a base, shaft, and head, with the concave lateral and medial borders of the shaft allowing attachment of the interossei muscles.
  • The digits are named in a similar fashion to the metacarpals, moving lateral to medial, and starting at the thumb.

• Femur (The Thigh)

  • Immediately lateral to the head is the neck that connects the head with the shaft.
  • Located superiorly on the main shaft, lateral to the joining of the neck, the greater trochanter is a projection to which the abductor and lateral rotator muscles of the leg attach.
  • Two rounded regions, termed the medial and lateral condyles, articulate with the tibia at the most anterior projection of the patella.
  • Finally, the two epicondyles, the medial and lateral, lie immediately proximal to the condyles; they are also regions where key internal knee ligaments attach.