Sheet number six !!

The Upper limb consists of:
1- Forearm.
2- Upper arm.
3- Hand.


Forearm :
-Bones of the forearm are two in number: Radius and Ulna.

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1) Radius:
- Lateral bone.
- Long bone.
- Bowing laterally.
- Has 3 parts:
1- Proximal end.
2- Shaft.
3- Distal end.

1- Proximal end: has the following parts:
A- Head: disc-shaped, articulates with Capitulum.
B- Neck: narrow part, good clinical landmark marking the site of division of Brachial artery into Radial and Ulnar arteries.
C- Radial tuberosity: insertion site for biceps muscle.
2- Shaft: it’s bowing lateral at its summit located bronator tuberosity.
3- Distal end: has the following parts:
A- Styloid process.
B- Inferior articuler surface that articulates with Scaphoid and Lunate directly.
C- Anterior surface of the distal end: it’s the common side to feel the pulse of Radial artery.


2- Ulna:
- Medial bone.
- Long bone.
- Subcutaneous.
- Wrench-like: with a cavity to hold Trochlea.
- Has the following parts:
A) Proximal end.
B) Shaft.
C) Distal end.

A) Proximal end:
- It’s like the mouth with two teeth.
- It has the following parts:
1) Trochlear fossa: to articulate with Trochlea.
2) Olecranon process: insertion site for triceps.
3) Coronoid process.
4) Tuberosity of Ulna: insertion for Brachialis muscle.

B) Shaft:
- Subcutaneous.
C) Distal end: has the following parts:
1) Styloid process of Ulna.
2) Inferior articular surface that articulates Triquetrum and Pisiform indirectly, separated by atricular disc which acts as a shock absorber when we fall on out stretched hand.



Upper Arm:
- Extending between shoulder and elbow.
- Covered by the following layers:
1) Skin.
2) Superficial fascia that contains:
a- Cephalic vein.
b- Baselic vein.
c- Large amount of fat.
3) Deep fascia: forms a cylinder around the structures in the upper arm and gives two partitions to the Humerus:
a- Lateral intermuscular septum.
b- Medial intermuscular septum.
separating the deep condense into anterior compartment and posterior compartment. Each of these compartments has its own muscles, own nerve supply, own arterial supply and own common action.

Anterior compartment:
- Contains 3 muscles:
1-Biceps muscle.
2- Brachialis muscle.
3- Coracobrachialis muscle.
- Nerve supply: musculocutaneous nerve (MCN).
- Arterial supply: Brachial artery.
- Common action: flexion of elbow.


Biceps:
- Origin: 2 heads:
a) Short from Coracoid process.
b) Long from Supraglenoid tubercle of Scapula.
- Insertion: Radial tuberosity.
- Action: - prime supinator of elbow.
- assist in flexion of elbow.
- adduct and flex the shoulder joint
- Nerve supply: musculocutaneous nerve (MCN).

Brachialis:
- Deep to biceps.
- Origin: Brachium.
- Insertion: Ulnar tuberosity.
- Nerve supply: musculocutaneous nerve (MCN).
- Action: prime flexor of the elbow.

Coracobrachialis:
- Named according to origin and insertion.
-Origin: Coracoid process of Scapula.
- Insertion: midshaft of Humerus.
- Nerve supply: musculocutaneous nerve (MCN).
- Action: Assists in flexion and adduction of the shoulder.

NOTE:
# The muscles which are attached to Coracoid process are:
- Pectoralis minor.
- Coracobrachialis.
- Biceps.
# Coracoid process receives muscle innervated by the following nerves:
- Pecto. minor: medial pectoral nerve.
- Coraco & short head: musculocutaneous nerve (MCN).

T H E E N D



A7la ta7eya for all my friends, specially:
Wa2el Towqan, Far7an, 3bdelra7man 3attili, Fadi Halasa, Ayoub 3ennabi, Soso 3abdeen, A7mad 3abed, 7amza Jassar, Bashar Alrama7i, Bashar Sharma, Summer, Muna, 5aled 7ajir, Martin Kakish, Hammam Ryalat, Mohammed Shawaf, 3esa 3akeel, Elham El8dah, Batool El3toom, 3’aleb 5erfan, Dina 3ammari (Dair), 3omar Radayda, Abu Haneye, Bilal Abu Dhaim, 3amer 7ajjaj, Bandar,Ma2mon Sha3ban, Momani, Ayman D3ja, M. Abu 5alaf(docor saydali), Amr Elfar (Engineering), Moh 5alil (Mo2ta uni.), Laith Bdour(JUST), Amr El7amad (Somayya uni.), 3koor (Sumayya uni.), Tsonami(a7la salam min 3attili ;-) and for all JUBILIANS. I HOPE I MENTIONED THEM ALL…..

Best Wishes
A7mad El3esa