Chest cavity, and back muscles. Respiratory muscles.

Sándor Katz M.D., Ph.D. Chest cavity - bony structures Chest cavity- bony structures Sternum Ribs

True ribs: first seven pairs connect to the sternum directly by costal cartilages.

False ribs: remaining five pairs connect to the sternum indirectly, forming costal arch. Last two pairs: floating ribs. Ribs Ribs Vertebral column General vertebral features First cervical - Atlas

1: anterior tubercle 2: anterior arch 3: fovea dentis 4: transverse process 5: transverse foramen 6: superior articular facet 7: posterior arch 8: posterior tubercle 9: vertebral foramen Second cervical vertebra - Axis

1: dens axis 2: superior articular process 3: vertebral body 4: lamina 5: vertebral arch 6: inferior articular process 7: transverse process 8: spinous process Atlas and Axis

1: dens axis 2: transverse foramen 3: spinous process 4: anterior arch 5: posterior arch 6: transverse process 7: superior articular facet Cervical vertebrae Costovertebral attachments Sacrum Intervertebral discs (Synchondroses) (A type of the continuous bony connections.) Atlanto-occipital

Ellipsoid (condylar) joint.

Ligaments: posterior and anterior atlanto-occipital membrane.

Permitted movements: flexion-extension, slight lateral flexion Atlanto-axial joint

PIVOT PART: Anterior median atlanto-axial joint: Between the dens axis (ant. articular facet) and fovea dentis of the atlas.

Posterior median atlanto-axial joint: Between the dens axis (post. articular facet) and transverse of atlas.

PLANE PART: Lateral atlanto-axial joint: Between the .

MOVEMENTS: 50% of the cervical rotation (50°) comes from the atlanto-axial joint. Flexion: 10°. Extension is really limited.

Zygapophysial (facet) joint

Cevical region: All movements are possible such as flexion, extension, lateral flexion and rotation.

Thoracic region: Lateral flexion and rotation. No flexion/extension.

Lumbar reion: Flexion and extension. Covering structures Covering structures Spinal curvatures Scoliosis (S-shaped deformity of the spine) Superficial back muscles - spinohumeral muscles

Trapezius: acromial third of clavicle, acromion, spine of scapula

Levator scapulae: superior angle of scapula

Rhomboid minor, major: medial border of scapula

Latissimus dorsi: crest of lesser tubercle

Function: Move the upper limb. Deep (axial) muscles

Erector spinae muscle (longissimus+iliocostalis)

Spinalis muscles

Functions:

Unilateral innervation: lateral flexion.

Bilateral innervation: extension. Transversospinal muscles (from transverse processes to spinous processes)

Semispinalis muscles: Cover 5-6 vertebrae.

Multifidi muscles: Cover 3-4 vertebrae.

Rotatores muscles: Cover 1-2 vertebrae.

Functions:

Unilateral innervation: lateral flexion.

Bilateral innervation: extension. Respiratory muscles

• Intercostalis muscles

• Diaphragm

• Accessory muscles Intercostalis muscles

External intercostal muscles:

Arise from the lower border of the ribs and insert on the upper border of the ribs below.

Function: Elevation of the ribs, they reinforce the intercostal space during the deep inspiration.

Internal intercostal muscles:

Arise from the ridge of the inner surface of ribs and insert on the inferior border of the ribs above.

Function: Depression of the ribs, they reinforce the intercostal space during the deep expiration. Diaphragm (inspiration)

CENTRAL TENDON Caval hiatus for the inferior vena cava - T8

MUSCULAR PART: • Sternal part Superior epigastric artery.

• Costal part

• Lumbar part: Left and right crus and both have medial and lateral parts. Esophageal hiatus for the esophagus - T12 Aortic hiatus for the aorta and thoracic duct - L1 No hiatus for the azygos and hemiazygos veins and greater and lesser splanchnic nerves - L2 Movements of the thoracic wall during breathing

A: Pump handle movement of ribs and sternum.

B: Bucket handle movement of ribs. Accessory respiratory muscles

Inspiration: scalene muscles and sternocleidomastoid.

Expiration: abdominal muscles. Thank you for your attention.

Reference: Gray’s Anatomy for Student Thieme Atlas of Anatomy