posterior

Examples of posterior in the following topics:

• The Posterior Pituitary

  • The posterior pituitary (or neurohypophysis) comprises the posterior lobe of the pituitary gland and is part of the endocrine system.
  • Classification of the posterior pituitary varies, but most sources include the three regions below: Pars nervosa, also called the neural lobe or posterior lobe, constitutes the majority of the posterior pituitary and is the storage site of oxytocin and vasopressin.
  • Median eminenceL this is only occasionally included as part of the posterior pituitary.
  • However, only in mammals does the posterior pituitary have a compact shape.
  • Identify the location of the posterior pituitary and the hormones associated with it

• Posterior Muscles

  • Posterior muscles can be split into three groups depending on their physiological location.
  • Serratus Posterior Superior - The serratus posterior superior is a thin, rectangular shaped muscle lying below the rhomboid muscles.
  • Serratus Posterior Inferior - The serratus posterior inferior is broad muscle lying beneath the latissimus dorsi.
  • Highlighted in orange, the latissimus dorsi is a muscle of the posterior torso
  • Describe the location and movements of the posterior muscles of the trunk

• Cervical Plexus

  • The branches of the cervical plexus emerge from the posterior triangle at the nerve point, a point which lies midway on the posterior border of the sternocleidomastoid.
  • It innervates the scalp in the lateral area of the head posterior to the ear.
  • Transverse cervical nerve - The transverse cervical nerve (superficial cervical or cutaneous cervical) arises from the second and third cervical nerves, turns around the posterior border of the sternocleidomastoideus about its middle, and, passing obliquely forward beneath the external jugular vein to the anterior border of the muscle, it perforates the deep cervical fascia and divides beneath the platysma into ascending and descending branches, which are distributed to the antero-lateral parts of the neck.
  • They emerge beneath the posterior border of the sternocleidomastoideus, and descend in the posterior triangle of the neck beneath the platysma and deep cervical fascia
  • There are two additional branches that are formed by the posterior roots of the spinal nerves:

• Arteries of the Pelvis and Lower Limbs

  • At the most superior border of the greater sciatic foramen, the large opening to the rear of the pelvis, the internal iliac artery divides into anterior and posterior trunks.
  • The posterior trunk gives rise to arteries that supply the posterior pelvic wall and the gluteal region including the iliolumbar artery which supplies the psoas major muscle, the lateral sacral arteries and the superior gluteal artery.
  • The division of the internal iliac artery into its posterior and anterior trunks.

• Control of the Pituitary Gland by the Hypothalamus

  • The pituitary gland consists of the anterior pituitary and the posterior pituitary.
  • The pituitary gland consists of two components: the anterior pituitary (or adenohypophysis) and the posterior pituitary (or neurohypophysis), and is functionally linked to the hypothalamus by the pituitary stalk (also named the "infundibular stem", or simply the "infundibulum").
  • Whilst the pituitary gland is known as the 'master' endocrine gland, both of the lobes are under the control of the hypothalamus; the anterior pituitary receives its signals from the parvocellular neurons and the posterior pituitary receives its signals from magnocellular neurons.

• Muscles of the Humerus that Act on the Forearm

  • There are four muscles in the upper arm split into an anterior and posterior compartment.
  • The posterior compartment of the upper arm contains only one muscle.
  • The posterior compartment of the forearm is split into superficial and deep regions.
  • Brachioradialis - The brachioradialis is located in the superficial region of the forearm posterior compartment,
  • Supinator - The supinator is located in the deep region of the forearm posterior compartment.

• Glossopharyngeal (IX) Nerve

  • It receives general sensory fibers (ventral trigeminothalamic tract) from the tonsils, the pharynx, the middle ear, and the posterior 1/3 of the tongue.
  • It receives special sensory fibers (taste) from the posterior 1/3 of the tongue.
  • General sensory (general somatic afferent) - provides general sensory information from the skin of the external ear, internal surface of the tympanic membrane, upper pharynx, and the posterior 1/3 of the tongue.
  • Special sensory (special afferent) - provides taste sensation from the posterior 1/3 of the tongue.

• Muscles that Cause Movement at the Ankle

  • There are several muscles located in the posterior compartment of the leg and they are typically grouped into superficial and basal groups, the majority of which function to plantarflex the foot at the ankle.
  • Gastrocnemius- The gastrocnemius is a two headed muscle and is the most superficial of the muscles in the posterior compartment.
  • Tibialis Posterior - The tibialis posterior is the deepest lying of the muscles in the posterior compartment.
  • Posterior view of leg showing muscles and tendons involved in ankle movement.

• Patella (The Knee)

  • The posterior surface of the patella contains the medial and lateral facets which articulate with the condyles of the femur.
  • The lower posterior region of the patella has vascular canaliculi, small channels within the bone, which form the infrapatellar fat pad.

• Muscles that Cause Movement at the Knee Joint

  • Muscles which generate movement across the knee are mainly located in the thigh and can be split into anterior or posterior compartments.
  • There are three muscles in the posterior compartment of the thigh, the biceps femoris and two synergistic muscles the semitendinosus and semimembranosus, with these muscles sometimes termed the hamstring group.
  • The posterior region of the thigh displays similarity with the anterior region of the upper arm in both structure and function.
  • Attachments: Originates from the posterior of the tibia and attaches to the femur.
  • Posterior view of muscles of the lower leg, the popliteus can be seen at the top located behind the knee.