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Anatomy

Hip

Constitutes the pelvic girdle
United with the vertebral column
Union of three parts that is marked by a cup shaped cavity (acetabulum) Ilium
•    Prominence of the hip
•    Superior border is the crest
•    Anterosuperior spine-projection at the anterior tip of the crest
•    Corresponding projections on the posterior part are the posterosuperior and posteroinferior iliac spines
•    Greater sciatic notch-located beneath the posterior part
•    Most is a smooth concavity (iliac fossa)
•    Posteriorly it is rough and articulates with the sacrum in the formation of the sacroiliac joint

Pubic bone

Anterior part of the innominate bone
Symphysis pubic-joining of the two pubic bones at the midline
Body and two rami 
•    Body forms one fifth of the acetabulum
•    Superior ramis extends from the body to the median plane: superior border forms the pubic crest
•    Inferior ramus extends downward and meets with the ischium
•    Pubic arch is formed by the inferior rami of both pubic hones

Ischium
    Forms the lower and back part of the innominate bone
    Body
•    Forms two fifths of the accrabulum
•    Ischial tuberosiry-supports the body in a sitting position
•    Ramus-passes upward to join the inferior ramus of rhe pubis; known as rhe obturator foramen

Pelvis

Fanned by the right and left hip bones, sacrum, and coccyx

Greater pelvis

o    Bounded by the ilia and lower lumbar vertebrae
o    Gives support to the abdominal viscera

Lesser pelvis

o    Brim of the pelvis corresponds to the sacral promontory
o    Inferior outlet is bounded by the tip of the coccyx, ischial tuberosities, and inferior rami of the pubic bones

Female pelvis

o    Shows adaptations related to functions as a birth canal Wide outlet
o    Angle of the pubic arch is obtuse

Male pelvis

o    Shows adaptations that contribute to power and speed
o    Heart-shaped outlet
o    Angle of the pubic arch is acute


Thigh

Femur-longest and strongest bone of the body
Proximal end has a rounded head that articulates with the acetabulum
Constricted portion-the neck
Greater and lesser trochanters
Slightly arched shaft; is concave posteriorly
o    Linea aspera-strengthened by this prominent ridge
o    Site of attachment for several muscles
Distal end has two condyles separated on the posterior side by the intercondyloid notch

Knee cap

Patella-sesamoid bone
Embedded in the tendon of the quadriceps muscle
Articulates with the femur


Leg

Tibia-medial bone
o    Proximal end has two condyles that articulate with the femur
o    Triangular shaft

    Anterior-shin
    Posterior-soleal line
    Distal-medial malleolus that articulates with the latus to form the ankle joint
Fibula-lateral bone
o    Articulates with the lateral condyle of the tibia but does not enter the knee joint
o    Distal end projects as the lateral malleolus


Ankle, foot, and toes

Adapted for supporting weight but similar in structure to the hand

Talus

o    Occupies the uppennost and central position in the tarsus
o    Distributes the body weight from the tibia above to the other tarsal bones
Calcaneus (heel)-Iocated beneath the talus
Navicular-located in front of the talus on the medial side; articulates with three cuneifonn bones distally
Cuboid-lies along the lateral border of the navicular bone

Metatarsals
o    First, second, and third p1etatarsals lie in front of the three cuneifonn bones
o    (2) Fourth and fifth metatarsals lie in front of the cuboid bone

Phalanges

o    Distal to the metatarsals
o    (2) Two in the great toe; three in each of the other four toes .

Longitudinal arches in the foot (2)

o    Lateral-fonned by the calcaneus, talus, cuboid, and fourth and fifth metatarsal bones
o    Medial-fonned by the calcaneus, talus, navicular, cuneifonn, and first, second, and third metatarsal bones

Transverse arches-formed by the tarsal and metatarsal bones

 

  • The palate has a rich blood supply from branches of the maxillary artery.

The Frontalis Muscle

  • The frontalis muscle is part of the scalp muscle called the occipitalfrontalis.
  • The frontalis elevates the forehead, giving the face a surprised look, and produces transverse wrinkles in the forehead when one frowns.

The Sublingual Glands

  • These are the smallest of the three paired salivary glands and the most deeply situated.
  • They are almond-shaped and lie in the floor of the mouth between the mandible and the genioglossus muscle.
  • The paired glands unite to form a horseshoe-shaped glandular mass around the lingual frenulum.
  • Numerous small ducts (10 to 12) open into the floor of the mouth.
  • Sometimes one of the ducts opens into the submandibular duct.
  • The nerves the accompany the submandibular and sublingual glands are derived from the lingual and chorda tympani nerves and from the sympathetic nerves.
  • The parasympathetic secretomotor fibres are from the submandibular ganglion.

Eye 

At week 4, two depressions are evident on each of the forebrain hemispheres.  As the anterior neural fold closes, the optic pits elongate to form the optic vesicles.  The optic vesicles remain connected to the forebrain by optic stalks. 
The invagination of the optic vesicles forms a bilayered optic cup.  The bilayered cup becomes the dual layered retina (neural and pigmented layer)
Surface ectoderm forms the lens placode, which invaginates with the optic cup.
The optic stalk is deficient ventrally to contain choroids fissure to allow blood vessels into the eye (hyaloid artery).  The artery feeds the growing lens, but will its distal portion will eventually degenerate such that the adult lens receives no hyaloid vasculature.
At the 7th week, the choroids fissure closes and walls fuse as the retinal nerve get bigger.
The anterior rim of the optic vesicles forms the retina and iris.  The iris is an outgrowth of the distal edge of the retina.
Optic vesicles induces/maintains the development of the lens vesicle, which forms the definitive lens.  Following separation of the lens vesicle from the surface ectoderm, the cornea develops in the anterior 1/5th of the eye.
The lens and retina are surrounded by mesenchyme which forms a tough connective tissue, the sclera, that is continuous with the dura mater around the optic nerve.  
Iridopupillary membrane forms to separate the anterior and posterior chambers of the eye.  The membrane breaks down to allow for the pupil
Mesenchyme surrounding the forming eye forms musculature (ciliary muscles and pupillary muscles – from somitomeres 1 and 2; innervated by CN III), supportive connective tissue elements and vasculature.


Eyelids

Formed by an outgrowth of ectoderm that is fused at its midline in the 2nd trimester, but later reopen.

The Hard Palate

  • The anterior bony part of the palate is formed by the palatine process of the maxillae and the horizontal plates of the palatine bones.
  • Anteriorly and laterally, the hard palate is bounded by the alveolar processes and the gingivae.
  • Posteriorly, the hard palate is continuous with the soft palate.
  • The incisive foramen is the mouth of the incisive canal.
  • This foramen is located posterior to the maxillary central incisor teeth.
  • This foramen is the common opening for the right and left incisive canals.
  • The incisive canal and foramen transmit the nasopalatine nerve and the terminal branches of the sphenopalatine artery.
  • Medial to the third molar tooth, the greater palatine foramen pierces the lateral border of the bony palate.
  • The greater palatine vessels and nerve emerge from this foramen and run anteriorly into two grooves on the palate.
  • The lesser palatine foramen transmits the lesser palatine nerve and vessels.
  • This runs to the soft palate and adjacent structures.

  • Articulations

    Classified according to their structure, composition,and movability
    •    Fibrous joints-surfaces of bones almost in direct contact with limited movement
        o    Syndesmosis-two bones united by interosseous ligaments
        o    Sutures-serrated margins of bones united by a thin layer of fibrous tissue
        o    Gomphosis-insertion of a cone-shaped process into a socket

    •    Cartilaginous joints-no joint cavity and contiguous bones united by cartilage
        o    Synchondrosis-ends of two bones approximated by hyaline cartilage
        o    Symphyses-approximating bone surfaces connected by fibrocartilage

    •    Synovial joints-approximating bone surfaces covered with cartilage; may be separated by a disk; attached by ligaments 
        o    Hinge-permits motion in one plane only
        o    Pivot-permits rotary movement in which a ring rotates around a central axis
        o    Saddle-opposing surfaces are convexconcave. allowing great freedom of motion
        o    Ball and socket - capable of movement in an infinite number of axes; rounded head of one bone moves in a cuplike cavity of the approximating bone

    Bursae
    •    Sacs filled with synovial fluid that are present where tendons rub against bone or where skjn rubs across bone
    •    Some bursae communicate with a joint cavity 
    •    Prominent bursae found at the elbow. hip, and knee'

    Movements
    •    Gliding
        o    Simplest kind of motion in a joint
        o    Movement on a joint that does not involve any angular or rotary motions
    •    Flexion-decreases the angle formed by the union of two bones
    •    Extension-increases the angle formed by the union of two bones
    •    Abduction-occurs by moving part of the appendicular skeleton away from the median plane of the body
    •    Adduction-occurs by moving part of the appendicular skeleton toward the median plane of the body
    •    Circumduction
        o    Occurs in ball-and-socket joints
        o    Circumscribes the conic space of one bone by the other bone
    •    Rotation-turning on an axis without being displaced from that axis
     

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