Ribs and Vertebrae Flashcards
What does a typical rib consist of?
Head, neck and body
Describe the head of a rib
- Wedge shaped - 2 articular facets separated by wedge of bone
What do the 2 articular facets on the head of the rib articulate with?
- One facet articulates with the vertebra above - The other articulates with the numerically corresponding vertebra E.g. The head of rib 2 articulates with the inferior demi facet of T1 and superior demi facet of T2
Describe the body/shaft of a rib
- Flat and curved - Internal surface has groove for neuromuscular supply of thorax (protecting vessels and nerves from damage) E.g. the shaft of rib 2 articulates with the costal facets of T2
Describe the neck of a rib
- No bony prominences - Connects head with body
What is present where the neck of the rib meets the body?
A roughened tubercle with a facet for articulation with the transverse process of the corresponding vertebrae
How is rib 1 atypical?
Has only 1 facet on its head for articulation with corresponding vertebrae (as there isn’t a thoracic vertebra above it) i.e. head articulates only with T1
Flat upper surface of rib may present groove for sublcavian artery and lower trubk of brachial plexus
Tubercle for sclaneus anterior muscle
What is the superior surface of rib 1 marked by?
2 grooves that make way for subclavian vessels
How is rib 2 atypical?
- Has 2 articular facets (as normal) - Has roughened area on upper surface from which serratus anterior muscle originates
i. e. presents tuberosity for serratus anterior muscle
How is rib 10 atypical?
Has only 1 facet for articulation with its numerically corresponding vertebra
How are ribs 11 and 12 atypical?
- Have no neck - Only contain 1 facet for articulation with their corresponding vertebrae
What joints does each rib form with the vertebrae of the spine?
- Costotransverse joint 2. Costovertebral joint
Where is the costotransverse joint?
Between the tubercle of the rib (where the neck of the rib meets the body), and the transverse costal facet of the corresponding vertebra
Where is the costovertebral joint?
Between the head of the rib, superior costal facet of the corresponding rib, and inferior costal facet of the vertebra above
Describe the function of the vertebral body of a thoracic vertebra?
- Vertebral body forms the anterior part of each rib - Is the weight-bearing component
Why do vertebrae in the lower portion of the column have larger bodies than those in upper portion?
To support increased weight
What does the combination of the vertebral arch and vertebral body form?
An enclosed hole –> the vertebral foramen
What do all the foramina of all vertebrae line up to form?
The vertebral canal which encloses the spinal cord
Where are the transverse processes?
Each vertebra has 2 transverse processes which extend laterally and posteriorly from the vertebral body (off right and left side)
What do the transverse processes articulate with?
Point of articulation with ribs –> there is a costal facet for articulation with the shaft of a single rib
What is the spinous process?
Each vertebra has a single spinous process, centred posteriorly at the point of the arch
What are the lamina?
Connect the transverse and spinous processes
What does each thoracic vertebra have on each side of the vertebral body?
2 demi facets –> superiorly and inferiorly placed on either side of its vertebral body These articulate with the heads of 2 different ribs
Where are the costal facets found?
On the transverse process (present on T1-T10 only)
What do the costal facets articulate with?
The tubercles of the ribs
What do spinous processes offer?
Increased protection to the spinal cord
How are the heads of the ribs joined to the vertebrae?
- 1st and last 3 ribs have a single synovial joint with the corresponding vertebrae
- The remaining ribs have two synovial joints: one with the corresponding vertebra and one with the immediate avoe
These joints are formed by the heads of the ribs with the body of the vertebrae
How are the tubercles of each rib joined to the vertebrae?
The tubercle of each rib articulates with the transverse process of the corresponding vertebrae through a synovial joint (The tubercles are absent on the eleventh and twelfth ribs and therefore no such joints occur for these ribs)
What is found on the superior surface of rib 1?
Marked by 2 grooves –> make way for subclavian vessels
What does the tubercle of the rib articulate with?
Transverse process of corresponding vertebrae
