Chest cavity, vertebral column and back muscles. Respiratory muscles. Sándor Katz, M.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

Atlas and axis

Cervical vertebrae

Thoracic vertebrae

Costovertebral attachments

Lumbar vertebrae

Sacrum

Synchondrosis (A type of the continuous bony connections.)

Atlanto-occipital joint Condylar joint. Ligaments connecting the bones are: posterior atlanto-occipital membrane 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 ligament of atlas. PLANE PART: Lateral atlanto-axial joint: Between the articular processes. 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 spine)

Superficial back muscles-spinohumeral muscles Function: Move the upper limb.

Deep (axial) muscles Functions: Unilateral innervation: lateral flexion. Bilateral innervation: extension.

Transversospinal muscles (from a transverse process to a spinous process) 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: Elevate the ribs, reinforce the intercostal space in 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. Depress the ribs, reinforce the intercostal space in deep expiration.

Diaphragm (inspiration) CENTRAL PART Caval hiatus for inferior vena cava.-T8 MUSCULAR PART: Sternal part Superior epigastric artery. Costal part Lumbar part: Left/right crus and both have medial and lateral parts. Esophageal hiatus for esophagus.-T12 Aortic hiatus for aorta and thoracic duct.-L1 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 Students