W.3.1 Thorax

Suprapleural membranes

The roof of the thorax.

Vertebral bodies

The posterior boundary of the thorax.

Costal cartilages

The anterior boundary of the thorax.

Ribs 1-7

Attached to the sternum via their own costal cartilage.

Ribs 8-10

Attach to the sternum by hitchhiking with the 7th costal cartilage.

Ribs 11-12

No anterior articulation.

Typical ribs (3-10)

Have a head that articulates with the vertebrae.

Costal groove

A channel along the inferior surface of the rib.

Grooves for subclavian a. & v.

Found on atypical ribs.

Tuberosity for serratus anterior

Atypical ribs possess this tuberosity.

Single facet on head

Only found on ribs 1, 11, and 12 which articulate directly with one vertebral body.

Costochondral joint

Joint formed between the costal cartilage and the rib.

Costotransverse joint

Joint formed between rib tubercle and transverse process of the vertebra.

Potential space

The pleural cavity is an example of this.

Pleural fluid

Lining inside the pleural cavity provides surface tension.

Mediastinum

Space between the lungs that contains heart and major vessels.

Pleura

Membranes surrounding the lungs.

Visceral pleura

Sticks to parietal pleura via surface tension.

Inspiration

The phase of breathing in.

Expiration

The phase of breathing out.

Quiet respiration

A passive process involving elastic recoil.

Forced respiration

An active process involving muscle contraction.

Thoracic diaphragm

Muscle responsible for respiration.

Central tendon

Part of the diaphragm that centralizes muscle action.

Aortic hiatus

Opening in the diaphragm for the aorta.

Oesophageal hiatus

Opening in the diaphragm for the esophagus.

Caval opening

Opening in the diaphragm for the inferior vena cava.

Intercostal muscles

Muscles located between the ribs.

Elevates ribs

Function of the diaphragm during inspiration.

Passive Inspiration

Process where air is drawn into lungs without muscle contraction.

Force inspiration

Muscle activity increases thoracic volume.

Rib movements

Describe the action of ribs during breathing.

Intercostal neurovascular bundle

Contains intercostal vein, artery, and nerve.

Splanchnic lateral plate mesoderm

Forms the gut tube and is innervated by primitive gut.

Somatic lateral plate mesoderm

Forms the body wall and is associated with surface ectoderm.

Intercostal nerve

Innervates the outer edges of the diaphragm.

Demifacets

Characteristics of rib articulations with vertebrae.

Costocorporeal joint

Joint formed by the head of a rib with vertebral body.

Cap for costal cartilage

Protective feature absent in atypical ribs.

Short ribs

Ribs 11 and 12, which lack neck or tubercle.

Pleural cavity

An open space that contains the lungs.

Intra-articular ligament

Ligament present in the articulation of ribs.

Costal margin

Lower border of the rib cage.

Elevation and depression

Axis of movement for rib rotation.

Active muscle contraction

Critical for forced respiration.

Serous membranes

Thin membranes that line body cavities.

Abdominal cavity

Cavity containing digestive organs.

Pelvic cavity

Cavity containing reproductive organs.

Surface tension

Property of pleural fluid vital for lung expansion.

-C3, 4, 5: Keep the diaphragm alive

Mnemonic for diaphragm innervation.

Spinal nerves

Provide sensation and motor function to the thoracic region.

Costal articulation

The way ribs attach to vertebrae and the sternum.

Axis of rotation

Pivot point for rib movement during respiration.

Thorax anatomical overview

General reference to the structure encompassing ribs and respiratory system.