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Anatomy

The Middle Ear

 

  • This part of the ear is in a narrow cavity in the petrous part of the temporal bone.
  • It contains air, three auditory ossicles, a nerve and two small muscles.
  • The middle ear is separated from the external acoustic meatus by the tympanic membrane.
  • This cavity includes the tympanic cavity proper, the space directly internal to the tympanic membrane, and the epitympanic recess, the space superior to it.
  • The middle ear is connected anteriorly with the nasopharynx by the auditory tube.
  • Posterosuperiorly, the tympanic cavity connects with the mastoid cells through the aditus ad antrum (mastoid antrum).
  • The tympanic cavity is lined with mucous membrane that is continuous with the mucous membrane of the auditory tube, mastoid cells, and aditus ad antrum.

Contents of the Tympanic Cavity or Middle Ear

  • This cavity contains the auditory ossicles (malleus, incus and stapes); the stapedius and tensor tympani muscles; the chorda tympani nerve (a branch of the facial nerve, CN VII); and the tympanic plexus of nerves.

Veins of the Face

The Supratrochlear Vein

  • This vessel begins on the forehead from a network of veins connected to the frontal tributaries of the superficial temporal vein.
  • It descends near the medial plane with its fellow on the other side.
  • These veins diverge near the orbits, each joining a supraorbital vein to form the facial vein near the medial canthus (angle of the eye).

 

The Supraorbital Vein

  • This vessel begins near the zygomatic process of the temporal bone.
  • It joins the tributaries of the superficial and middle temporal veins.
  • It passes medially and joins the supratrochlear vein to form the facial vein near the medial canthus.

 

The Facial Vein

  • This vein provides the major venous drainage of the face.
  • It begins at the medial canthus of the eye by the union of the supraorbital and supratrochlear veins.
  • It runs inferoposteriorly through the face, posterior to the facial artery, but takes a more superficial and straighter course than the artery.
  • Inferior to the margin of the mandible, the facial vein is joined by the anterior branch of the retromandibular vein.
  • The facial veins ends by draining into the internal jugular vein.

 

The Superficial Temporal Vein

  • This vein drains the forehead and scalp and receives tributaries from the veins of the temple and face.
  • In the region of the temporomandibular joint, this vein enters the parotid gland.

 

The Retromandibular Vein

  • The union of the superficial temporal and maxillary veins forms this vessel, posterior to the neck of the mandible.
  • It descends within the parotid gland, superficial to the external carotid artery but deep to the facial nerve.
  • It divides into an anterior branch that unites with the facial vein, and a posterior branch that joins the posterior auricular vein to form the external jugular vein.

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

Muscles Around the Eyelids

  • The function of the eyelid (L. palpebrae) is to protect the eye from injury and excessive light. It also keeps the cornea moist.

The Orbicularis Oculi Muscle

  • This is the sphincter muscle of the eye.
  • Its fibres sweep in concentric circles around the orbital margin and eyelids.
  • It narrows the eye and helps the flow of tears from the lacrimal sac.
  • This muscle has 3 parts: (1) a thick orbital part for closing the eyes to protect then from light and dust; (2) a thin palpebral part for closing the eyelids lightly to keep the cornea from drying; and (3) a lacrimal part for drawing the eyelids and lacrimal punta medially.
  • When all three parts of the orbicularis oculi contract, the eyes are firmly closed and the adjacent skin becomes wrinkled.
  • The zygomatic branch of the facial nerve (CN VII) supplies it.

The Levator Palpebrae Superioris Muscle

  • This muscle raises the upper eyelid to open the palpebral fissure.
  • It is supplied by the oculomotor nerve (CN III).

Appendicular Skeleton
Upper extremity
•    Shoulder-clavicle and scapula

Clavicle
    Articulates with the manubrium at the sternal end
    Articulates with the scapula at the lateral end
    Slender S-shaped bone that extends horizontally across the upper part of the thorax
    
Scapula

    Triangular bone with the base upward and the apex downward
    Lateral aspect contains the glenoid cavity that articulates with the head of the humerus
    Spine extends across the upper part of the posterior surface; expands laterally and
    forms the acromion (forms point of shoulder) 
    Coracoid process projects anteriorly from the upper part of the neck of the scapula
    
Arm (humerus)

Consists of a shaft (diaphysis) and two ends (epiphyses)
Proximal end has a head that articulates with the glenoid fossa of the scapula
Greater and lesser tubercles lie below the head

Intertubercular groove is located between them; long tendon of the biceps attaches here
Surgical neck is located below the tubercles

    o    Radial groove runs obliquely on the posterior surface; radial nerve is located here

    o    Deltoid muscles attaches in a V-shaped area in the middle of the shaft. called the deltoid tuberosity
    
Distal end has two projections. the medial and lateral epicondyles
Capitulum-articulates with the radius
Trochlea-articulates with the ulqa

Forearm

Radius
Lateral bone of the forearm
Radial tuberosity is located below the head on the medial side
Distal end is broad for articulation with the wrist: has a styloid process on its lateral side

Ulna

    Medial side of the forearm
    Conspicuous part of the elbow joint (olecranon)
    Curved surface that articulates with the trochlea of the humerus is the trochlearnotch
    Lateral ide is concave (radial notch); articulates with the head of the radius Distal end contains the styloid process 
    Distal end contains the styloid process

Hand

Carpal bones (8)
    Aranged in two rows of four
    Scaphoid. lunate. triquetral. and pisiform  proximal row); trapezium. trapezoid.
    capitate. and hamate (distal row)
    
Metacarpal bones (5)
    Framework of the hand
    Numbered 1 to 5 beginning on the lateral side
    
Phalanges (14)
    Fingers
     Three phalanges in each finger; two phalanges in the thumb

 

  • This is the posterior curtain-like part, and has no bony support. It does, however, contain a membranous aponeurosis.
  • The soft palate, or velum palatinum (L. velum, veil), is a movable, fibromuscular fold that is attached to the posterior edge of the hard palate.
  • It extends posteroinferiorly to a curved free margin from which hangs a conical process, the uvula (L. uva, grape).
  • The soft palate separates the nasopharynx superiorly and the oropharynx inferiorly.
  • During swallowing the soft palate moves posteriorly against the wall of the pharynx, preventing the regurgitation of food into the nasal cavity.
  • Laterally, the soft palate is continuous with the wall of the pharynx and is joined to the tongue and pharynx by the palatoglossal and palatopharyngeal folds.
  • The soft palate is strengthened by the palatine aponeurosis, formed by the expanded tendon of the tensor veli palatini muscle.
  • This aponeurosis attaches to the posterior margin of the hard palate.

  • Long bones (e.g.. femur and humerus)
  • Short bones (e.g.. wrist and ankle bones)
  • Flat bones (e.g.. ribs)
  • Irregular bones (e.g.. vertebrae)

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