NEET MDS Lessons
Anatomy
Muscles of the Soft Palate
The Levator Veli Palatini (Levator Palati)
- Superior attachment: cartilage of the auditory tube and petrous part of temporal bone.
- Inferior attachment: palatine aponeurosis.
- Innervation: pharyngeal branch of vagus via pharyngeal plexus.
- This cylindrical muscle runs inferoanteriorly, spreading out in the soft palate, where it attaches to the superior surface of the palatine aponeurosis.
- It elevates the soft palate, drawing it superiorly and posteriorly.
- It also opens the auditory tube to equalise air pressure in the middle ear and pharynx.
The Tensor Veli Palatini (Tensor Palati)
- Superior attachment: scaphoid fossa of medial pterygoid plate, spine of sphenoid bone, and cartilage of auditory tube.
- Inferior attachment: palatine aponeurosis.
- Innervation: medial pterygoid nerve (a branch of the mandibular nerve).
- This thin, triangular muscle passes inferiorly, and hooks around the hamulus of the medial pterygoid plate.
- It then inserts into the palatine aponeurosis.
- This muscle tenses the soft palate by using the hamulus as a pulley.
- It also pulls the membranous portion of the auditory tube open to equalise air pressure of the middle ear and pharynx.
The Palatoglossus Muscle
- Superior attachment: palatine aponeurosis.
- Inferior attachment: side of tongue.
- Innervation: cranial part of accessory nerve (CN XI) through the pharyngeal branch of vagus (CN X) via the pharyngeal plexus.
- This muscle, covered by mucous membrane, forms the palatoglossal arch.
- The palatoglossus elevates the posterior part of the tongue and draws the soft palate inferiorly onto the tongue.
- Superior attachment: hard palatThe Palatopharyngeus Musclee and palatine aponeurosis.
- Inferior attachment: lateral wall of pharynx.
- Innervation: cranial part of accessory nerve (CN XI) through the pharyngeal branch of vagus (CN X) via the pharyngeal plexus.
- This thin, flat muscle is covered with mucous membrane to form the palatopharyngeal arch.
- It passes posteroinferiorly in this arch.
- This muscle tenses the soft palate and pulls the walls of the pharynx superiorly, anteriorly and medially during swallowing.
The Musculus Uvulae
- Superior attachment: posterior nasal spine and palatine aponeurosis.
- Inferior attachment: mucosa of uvula.
- Innervation: cranial part of accessory through the pharyngeal branch of vagus, via the pharyngeal plexus.
- It passes posteriorly on each side of the median plane and inserts into the mucosa of the uvula.
- When the muscle contracts, it shortens the uvula and pulls it superiorly.
Gross anatomy-study of structures that can be identified with the naked eye; usually involves the use of cadavers
- Microscopic anatomy (histology)-study of cells that compose tissues and organs; involves the use of a microscope to study the details of the species
- Developmental anatomy (embryology)-study of an individual from beginning as a single cell to birth
- Comparative anatomy -comparative study of the animal structure in regard to similar organs or regions
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| Motor Innervation | All muscles by hypoglossal nerve (CN XII) except palatoglossus muscle (by the pharyngeal plexus) | ||
| General Sensory Innervation |
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| Special Sensory Innervation |
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- This is the second cranial nerve (CN II) and is the nerve of sight.
The Temporomandibular Joint
- This articulation is a modified hinge type of synovial joint.
- The articular surfaces are: (1) the head or condyle of the mandible inferiorly and (2) the articular tubercle and the mandibular fossa of the squamous part of the temporal bone.
- An oval fibrocartilaginous articular disc divides the joint cavity into superior and inferior compartments. The disc is fused to the articular capsule surrounding the joint.
- The articular disc is more firmly bound to the mandible than to the temporal bone.
- Thus, when the head of the mandible slides anterior on the articular tubercle as the mouth is opened, the articular disc slides anteriorly against the posterior surface of the articular tubercle
The Oropharynx
- The oral part of the pharynx has a digestive function.
- It is continuous with the oral cavity through the oropharyngeal isthmus.
- The oropharynx is bounded by the soft palate superiorly, the base of the tongue inferiorly, and the palatoglossal and palatopharyngeal arches laterally.
- It extends from the soft palate to the superior border of the epiglottis.
The Palatine Tonsils
- These are usually referred to as "the tonsils".
- They are collections of lymphoid tissue the lie on each side of the oropharynx in the triangular interval between the palatine arches.
- The palatine tonsils vary in size from person to person.
- In children, the palatine tonsils tend to be large, whereas in older persons they are usual small and inconspicuous.
- The visible part of the tonsil is no guide to its actual size because much of it may be hidden by the tongue and buried in the soft palate.
The Articular Capsule
- The capsule of this joint is loose.
- The thin fibrous capsule is attached to the margins of the articular area on the temporal bone and around the neck of the mandible.