Upper Limb: Compartments & Regions Flashcards
Describe the regions & sub-regions of the upper-limb
What are the (4) muscles of the Anterior & Lateral chest that are involved in arm movement?
Anterior Chest;
- Pectoralis Major
- Pectoralis Minor
- Subclavius
Lateral Chest;
- Serratus Anterior
What is the action of the Pectoralis Major?
Origin & Insertion?
Pectoralis Major:
Action:
- Adducts/ Medially Rotates Arm
- Aids in flexion & Extension of Humerus
Origin:
- Clavicle
- Sternum
- Costal Cartilages of upper Ribs
Insertion:
- Lip of intertubercular Sulcus (Lateral to the insertion of Latissmus Dorsi & Teres Major)
What is the action of the Pectoralis Minor?
Origin & Insertion?
Pectoralis Minor:
Action:
- Stabilizes the Scapula
Origin:
- Ribs near Costal Cartilage
Insertion:
- Coracoid Process
What is the action of the Subclavius?
Origin & Insertion?
Subclavius:
Action:
- Anchors & Depresses the Clavicle
Origin:
- First Rib
Insertion:
- Clavicle
What is the action of the Serratus Anterior?
Origin & Insertion?
Serratus Anterior:
Action:
- Protracts Scapula & Holds it against the thoracic wall
Origin:
- Lateral Surface of ribs
Insertion:
- Medial Border of Scapula
Describe, in general, the action, innervation, and blood supply of the Anterior Arm.
Which muscles are included?
What is the exception in innervation?
Anterior arm:
Action: Flexors of the Elbow & Shoulder, & Supination of the Forearm
Blood Supply: Brachial a.
Innervation: Musculocutaneous n. (& small amount of Radial n.)
* The Brachialis muscle receives a small contribution of innervation from the Radial n.
Muscles:
- Biceps Brachii
- Coracobrachialis
- Brachialis
What is the action of the Biceps Brachii?
Origin & Insertion?
The Biceps Brachii Flexes & Supinates the Forearm
Origin:
- Coracoid process (Short Head)
- Supraglenoid Tubercle (Long Head)
Insertion:
- Radial Tuberosity
- Bicipital Aponeurosis
What is the action of the Coracobrachialis?
Origin & Insertion?
The Coracobrachialis Flexes & Adducts the arm (weak)
Origin: Coracoid Process
Insertion: Midshaft of the Humerus
What is the action of the Brachialis?
Origin & Insertion?
The Brachialis flexes the Forearm
Origin: Distal Humeral Shaft
Insertion: Coronoid Process of the Ulna
*The Brachialis m. receives innervation from primarily the Musculocutaneous n., but also a small contribution from the Radial n.
What is the common Flexor Origin of the Forearm?
What about the common Extensor Origin?
Describe, in general, the action, innervation, and blood supply of the Anterior Forearm.
Muscles of the Anterior Forearm are primarily Flexors and Pronators.
Blood Supply: Radial & Ulnar aa.
Innvervation: Median & Ulnar nn.
What are the muscles of the anterior forearm?
(Lateral -> Medial)
Superficial:
- Pronator Teres (PT)
- Flexor Carpi Radialis (FCR)
- Palmaris Longus* (PL)
- Flexor Carpi Ulnaris (FCU)
Intermediate:
- Flexor Digitorum Superficialis (FDS)
Deep:
- Flexor Pollicis Longus (FPL)
- Flexor Digitorum Profundus (FDP)
- Pronator Quadratus (PQ)
What are the Superficial Anterior Forearm muscles?
Which has a differing innervation and what is it?
Which is variable?
- Pronator Teres (PT)
- Flexor Carpi Radialis (FCR)
- Palmaris Longus* (PL)
- Flexor Carpi Ulnaris (FCU)
The Flexor Carpi Ulnaris is innervated by the Ulnar n. instead of the Median n., like the rest of the superficial layer.
The Palmaris Longus is variable, as it is not present in 10-20% of the population.
Which muscle is considered the Intermediate Anterior Forearm?
The Flexor Digitorum Superficialis (FDS)
What are the muscles of the Deep Anterior Forearm?
Which has differing innervation and what is it?
Deep Anterior Forearm:
- Flexor Digitorum Profundus (FDP)
- Flexor Pollicis Longus (FPL)
- Pronator Quadratus (PQ)
Medial portion of the FDP m. is innervated by the Ulnaris n. while the Lateral portion remains consistent with the rest of the compartment (Median n.)
How do the Flexor Digitorum Superficialis & Profundus differ?
Both insert past the PIP joint, thus aids in flexion at the PIP
FDS inserts at the shafts of the MIDDLE Phalanges
FDP inserts at the shafts of the DISTAL phalanges
- Only muscle that crosses the DIP joint
What is the Cubital Fossa?
What are it’s boundaries?
The Cubital Fossa is a triangular depression on the anterior surface of the Elbow.
It’s boundaries are made up by;
- Superficial: Line from medial to lateral Epicondyle
- Lateral: Brachioradialis m.
- Medial: Pronator Teres m.
What are the contents of the Cubital Fossa?
Which vein lies superficial to the Cubital Fossa?
Contents;
- End of Brachial a.
- Tendon of Biceps Brachii
- Median n.
- Radial n.
Superficial Vein:
- Median Cubital Vein
What are the contents which pass through the Carpal Tunnel?
Tendons of;
- FDS
- FDP
- FPL
& The Median n.
