Tuesday, April 15, 2008

sheet no. 24

Ribs:

- 12 pairs.

- Flat bones with spongy tissue, binding the vertebra
posterior to the sternum anterior, via costal cartilage.

- they are classified into: ( the international classification)

1. True ribs: the ribs connecting directly to the sternum,(ribs 1-7).

2. False ribs: those connecting indirectly to the sternum, (ribs 8-12).

{8, 9, and 10}: connecting indirectly, but {11, and 12}: are called floating ribs; only connecting to abdominal muscles.

- 2nd classification, depending on major parts of the rib, where they are classified into:

typical and atypical ribs.

* Typical ribs:

Each typical rib has the following parts:

1. Head: with 2 facets: superior and inferior, where the inferior facet articulates with vertebra of the same number, because the head is articulating with 2 sequential vertebrae.

2. Neck: constricted part, related to vital structures, especially sympathetic trunk.

*** If the neck of the rib is fractured, the sympathetic part of the nervous system is affected.

3. Tubercles: they are 2 in number:

- Articular, inferior: articulates with transverse process of the vertebra of the same number.

- Non articular, superior: for a ligament (acting as a spring between intercostal spaces,binding ribs together for recoil).

4. Costal angle: where the rib changes its direction.It gives origin to serratus anterior muscle.

5. Body (shaft), which has:

Anterior surface, posterior surface/ superior,smooth rounded border, and inferior sharp border.
*At the inferior border there is costal groove, lodging (transmitting) intercostal VAN (vein, artery, nerve).

* Atypical ribs:

- They are: 1, 2, 11, & 12.

- They have missed parts.

~ The 1st rib:

. The shortest, the widest, and the most curved of ribs.

. Has:

1. Anterior border, posterior border.

2. Superior surface, inferior surface.

3. NO, but no, costal groove.

*Related Structures to the Superior Surface (from anterior to posterior) are the following:

1) Subclavian Vein.

2) Subclavian Artery.

3) Lower trunk of the brachial plexus. {if injured, causes paralysis of Ulnar nerve.}à[claw hand]

*those structures may be injured if clavicle or first rib are fractured.

Thoracic Vertebra:

Each vertebra has 2 parts:

- Body, anterior à for weight bearing-act as a shock absorber.

- Vertebral arch, posterior à for protection of spinal cord.

Note:

Nervous system in the body is divided into:

1. Somatic nervous system (voluntary); central and peripheral.

2. Autonomic nervous system (involuntary);sympathetic {wasting} and parasympathetic {conservative}.

* The sympathetic trunk is located on both sides of the vertebral column, anterior to the neck of ribs.Extending from base of skull to coccyx. Its function is: coding the spinal nerve to be sympathetic.


Sawsan Tabaza ...

I'd like to dedicate this sheet to my friends:

Sondos alkhtib (la telqa2eyyan!!!), Ruba Almohtaseb (You mute,, you not succeed!), and Lama Jamal (eltamneh sabteh :p ,, Allah yeft7 3laiky ya rb!!!).and to all my colleages .....

No comments: