Anatomy of the Thoracic Wall - Joints of the Thoracic Cage

Anatomy must be giving you a tough time. Isn’t it?
This video on the anatomy of the chest wall is definitely going to change your perspective on anatomy. You will be learning it in the easiest way possible.
▬ Thoracic Cage ▬▬▬▬▬▬▬▬▬▬
The thorax is the region between your neck and the abdomen, what you call your chest. The thoracic wall forms the boundary of the thoracic cavity. And, the skeleton of the thoracic wall, forms an osseocartilaginous cage-like unit, called the thoracic cage.
It is made up of the Sternum, ribs, costal cartilage, intercostal spaces, and vertebral column.
Thorax communicates with the root of the neck, through the superior thoracic aperture, and with the abdomen, through a large opening called the inferior thoracic aperture.
Now, the thorax is separated from the abdominal cavity, by the muscular diaphragm.
▬ Sternum ▬▬▬▬▬▬▬▬▬▬
Sternum Lies at the midline of the anterior chest wall. It is also called breastbone.
The sternum has an upper manubrium, the body of the sternum in the middle, and a xiphoid process at the bottom. At the superior border of the manubrium, a concave notch is formed, called a suprasternal notch. At the superolateral corner of the manubrium, lies the clavicular notch which holds the clavicle.
▬ Ribs and Costal Cartilages ▬▬▬▬▬▬▬▬▬▬
Ribs are the elongated, flattened, arched bones that extend from the thoracic vertebrae towards
the anterior thorax. There are 12 pairs of ribs normally. They are classified as:
👉 True Ribs
That articulate directly with the sternum (1st-7th pairs of ribs)
👉 False Ribs
That connects to the sternum via individual costal cartilages, which join together and attach collectively to the 7th costal cartilage. (8th-10th pairs of ribs)
👉 Floating Ribs
They have no anterior attachment for their costal cartilages (11th and 12th pairs of ribs).
A typical rib has a head, neck, tubercle, body, angle, and costal groove. 3rd to 9th ribs are typical ribs, while 1st, 2nd, 10th, 11th, and 12th are atypical ribs.
Costal Cartilages are bars of hyaline cartilage, which connect the upper seven ribs, directly to the lateral edge of the sternum, and connect the 8th, 9th, and 10th ribs to the cartilage, immediately above. Whereas, the cartilages of the 11th, and 12th ribs, end in the abdominal musculature.
▬ Joints of the Thoracic Cage ▬▬▬▬▬▬▬▬▬▬
Joints that link the various parts of the thoracic cage include manubriosternal joint, xiphisternal joint, sternocostal joint, costochondral joint, interchondral joint, costotransverse joint, and costovertebral joint. You can grab their details through the video.
▬ Thoracic Vertebrae ▬▬▬▬▬▬▬▬▬▬
There are 12 thoracic vertebrae in total. Only the thoracic vertebrae carry ribs, and these vertebrae have unique structures for that purpose. That includes a heart-shaped vertebral body, Demi-facets on the sides of each vertebral body, Coastal facets on the transverse processes, and long, spinous processes that slant inferiorly.
▬ Intercostal Muscles ▬▬▬▬▬▬▬▬▬▬
There are some narrow, and elongated spaces, that separate the adjacent ribs. These are 11 in number and are known as the intercostal spaces. Each space contains a neurovascular bundle and three layers of intercostal muscles. These are:
🟡 External intercostal muscles
🟡 Internal intercostal muscles
🟡 Innermost intercostal muscles
You can learn about the arteries, veins, lymphatics, and nerves of the thoracic wall in the video.
▬ Diaphragm ▬▬▬▬▬▬▬▬▬▬
The diaphragm is a thin musculotendinous structure. The diaphragm separates the thoracic and abdominal cavities and acts as a partition between them. The structures cross the diaphragm by passing through the holes present in it, known as hiatus.
There are 3 main openings in the diaphragm:
🟠 Caval Opening - transmits inferior vena cava and right phrenic nerve.
🟠 Esophageal Opening - transmits esophagus, Vagi left gastric vessels, and some lymphatics.
🟠 Aortic Hiatus - transmits the aorta, thoracic duct, and the azygos vein.
Arteries supplying the diaphragm are Superior phrenic arteries, inferior phrenic arteries, and the branches of internal thoracic arteries. While the veins of the diaphragm drain into the brachiocephalic veins in the neck, the azygos system of veins, or the abdominal veins.
The diaphragm is innervated by the phrenic nerves, composed of fibers from cervical nerves C3, C4, and C5.
This was just an overview of the video, you are going to find many more details about this in the video, with fun mnemonics to ease your learning.