Unit 1 gross anatomy of the chest
This presentation is the property of its rightful owner.
Sponsored Links
1 / 16

Unit 1: Gross Anatomy of the Chest PowerPoint PPT Presentation


  • 106 Views
  • Uploaded on
  • Presentation posted in: General

Unit 1: Gross Anatomy of the Chest. Part III: Muscles of Ventilation Reference & Reading: Egan's p.158-163. Muscles of Ventilation. Primary Muscles Diaphragm Intercostal muscles Accessory Muscles Scalenes Sternocleomastoid Pectoralis Major Abdominals. Diaphragm.

Download Presentation

Unit 1: Gross Anatomy of the Chest

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript


Unit 1 gross anatomy of the chest

Unit 1: Gross Anatomy of the Chest

Part III: Muscles of Ventilation

Reference & Reading: Egan's p.158-163


Muscles of ventilation

Muscles of Ventilation

  • Primary Muscles

    • Diaphragm

    • Intercostal muscles

  • Accessory Muscles

    • Scalenes

    • Sternocleomastoid

    • Pectoralis Major

    • Abdominals


Diaphragm

Diaphragm

  • Rises from costal margin

  • Connects at central tendon

  • Hemidiaphragms

  • Separates thorax from abdomen


Diaphragm function

Diaphragm - Function

  • Resting Position

  • When muscle contracts, drops floor of thoracic cavity down

  • Pulls air in


Intercostal muscles

Intercostal Muscles

  • Located between each rib pair

  • External Intercostals

  • Internal Intercostals


Intercostal muscles function

Intercostal Muscles - Function

  • Active during quiet breathing

  • Elevates ribs, ↑ thoracic volume - occurs closer to exhalation

  • At increased lung volumes, ribs are lowered

  • Stabilizes chest wall during large pressure changes

    Quiet Breathing – from www.gettyimages.com


Retractions

Retractions

  • Also called intercostal retractions

  • There is increased amount of negative pressure generated

  • Clinical sign of increased WOB; look at suprasternal notch

  • Retractions on infant


Accessory muscles inspiration

Collection of chest wall muscles

Help to increase thoracic space, by assisting the primary muscles:

Includes:

Scalene

Sternocleomastoid

Pectoralis

Trapezius

Accessory Muscles - Inspiration


Scalene muscles

Scalene Muscles

  • 3 muscles

    • Anterior

    • Medial

    • Posterior

  • Arise from lower 5 cervical vertebrae & connect to 2nd rib anteriorly

  • Function:

    • Normal

    • With increased WOB


Sternocledomastoids

Sternocledomastoids

  • Rise from manubrium & medial end of clavicle

  • Insert into the skull

  • Function:

    • Primary: supports head

    • Increased WOB: raises sternum up & out


Pectoralis muscles

Pectoralis Muscles

  • Rises from clavicle & anterior surface of sternum

  • Function:

    • Primary: hugging motion

    • With increased WOB: pulls opposite of primary function


Trapezius muscles

Trapezius Muscles

  • Arise from the occipital bone in the skull & all thoracic vertebrae; insert into clavicle

  • Function:

    • Primary: shrug shoulders; raise or lower arms

    • Increased WOB: Raises rib cage


Accessory muscles exhalation

Accessory Muscles - Exhalation

  • Used to forcibly exhale (cough, sneeze, etc)

  • Muscles used are the abdominal muscles

  • Collectively compress abdominal contents to push diaphragm up

  • Includes:

    • External & internal obliques

    • Transverse abdominals

    • Rectus abdominus


Internal external oblique

Internal & External Oblique

  • External Oblique: arise from lower 8 ribs

  • Internal Oblique: Arise from iliac crest& inguinal ligament

  • Fibrous aponeurosis


Transverse abdominis

Transverse Abdominis

  • Arises from:

    • costal cartilages

    • Iliac crest

    • Part of inguinal ligament

  • Connects to a aponeurosis


Rectus abdominis

Rectus Abdominis

  • Arises from pubic bones

  • Inserts into costal cartilages 5 -7

  • Contraction ↓ distance from xiphoid to pubis


  • Login