Brachial Plexus

Anatomie

The brachial plexus is a vital network of nerves that innervates the upper limb. 

1. Origin:

   – Arises from the anterior rami (nerve roots) of spinal nerves C5-T1.

   – These roots merge and split into trunks, which further divide into divisions.

 

2. Trunks:

   – Three trunks: superior, middle, and inferior.

   – Located in the neck and extend into the axilla (armpit).

 

3. Divisions:

   – Each trunk splits into anterior and posterior divisions.

   – These divisions contribute to the formation of cords.

 

4. Cords:

   – Three cords: lateral, medial, and posterior.

   – Named based on their relation to the axillary artery.

 

5. Terminal Branches:

   – Responsible for motor and sensory innervation of the upper limb:

     – Musculocutaneous, axillary, radial, median, and ulnar nerves.

 

6. Supraclavicular Branches:

   – Preterminal branches leaving the plexus at various points.

 

Causes of Damage:

• • Trauma: Forceful movements that stretch or compress the nerves (e.g., sports injuries, falls, vehicle accidents).
  • Birth-related: Newborns may sustain injury during delivery.
  • Inflammation, tumors, or radiation exposure can also affect the brachial plexus.

     

 

Symptoms of Brachial Plexus Injury:

• • • Pain, tingling, or numbness in the arm.
    • Weakness oder paralysis.
    • Loss of sensation.
    • Diminished reflexes.
    • Inability to use certain muscles.

       

 

Diagnostic Tests:

• Electromyography (EMG): Measures muscle electrical activity.
• Nerve conduction studies (NCS): Assesses nerve conduction speed.
• Magnetic resonance imaging (MRI): Provides detailed images of the brachial plexus.

 

 

References:

(1) Brachial plexus: Anatomy, branches and mnemonics | Kenhub. https://www.kenhub.com/en/library/anatomy/brachial-plexus.

(2) Brachial plexus | Radiology Reference Article | Radiopaedia.org. https://radiopaedia.org/articles/brachial-plexus.

(3) Anatomy 101: Brachial Plexus | The Hand Society. https://www.assh.org/handcare/blog/anatomy-101-brachial-plexus.

(4) Brachial plexus: Video, Anatomy, Definition & Function | Osmosis. https://www.osmosis.org/learn/Brachial_plexus.