Unit Four: Into to The Extremities & Brachial Plexus Flashcards
What is a tubercle?
A small rounded projection or process.
What is a tuberosity?
A large rounded projection that may be roughened.
What is a trochanter?
Very large, irregularly shaped process.
What is an epicondyle?
A raised area on or above a condyle.
What is a spine?
A sharp, slender projection.
What is a process?
A bony prominence.
What is a crest?
A narrow prominent ridge of bone.
What is a line?
A narrow ridge of bone.
What determines the range of motion of a muscle?
The length of the muscle fibers.
What determines the force of a muscle?
The cross-section area of the muscle.
Does a large muscle cross-section provides more or less force?
More force.
What is a condyle?
A rounded articular projection.
What is the head?
A bony expansion carried on a narrow neck.
What is the facet?
A smooth, near flat articular surface.
What is a foramen?
A round or oval opening through a bone.
What is the notch?
The indentation at the edge of a bone.
What is the fossa?
The shallow basin-like depression.
Can muscles only pull?
They can only pull.
How can synergists help the prime mover? (3)
- Contribute to movement. 2. Stabilize. 3. Cancel out unwanted motion.
Where do muscles with the opposite action lie?
On the opposite sides of a joint.
What divides limb muscles?
Compartments.
What are compartments?
Dense, fibrous connective tissue.
What do muscles in the same compartment have in common?
They have similar actions and act as synergists.
How many nerves are compartments often innervated by?
1.
What is more proximal, the attachment site or the insertion?
The attachment site.
What is the brachial plexus formed by?
The anterior rami (roots) of the spinal nerves C5-T1.
What does the brachial plexus travel within?
The axilla (armpit).
What are rami also called?
Roots.
What do roots unite to form?
Trunks.
What do portions of each trunk divide into?
Anterior and posterior divisions.
What do the anterior and posterior divisions unite to form?
Three cords: Posterior. Medial. Lateral.
What emerges from cords?
5 terminal branches.
What are the five terminal branches?
- Axillary. 2. Median. 3. Musculocutaneous. 4. Radial. 5. Ulnar.
What are the posterior divisions posterior to?
The auxillary artery.
What do the anterior division fibers innervate?
The anterior arm, forearm, and hand.
What do the posterior division fibers innervate?
The posterior arm, forearm, and hand.
What do nerve supplied by the proximal rami fibers (C5-C6) innervate?
Proximal muscles.
What do nerves supplied by the intermediate rami fibers (C6-C8) innervate?
Muscles that act at the elbow and wrist.
What do muscles supplied by the inferior rami fibers (C8-T1) innervate?
Distal (hand) muscles.
What action do muscles innervate by C5 have?
Shoulder abduction.
What action do muscles innervated by C6 have?
Elbow flexion.
What action do muscles innervated by C7 have?
Elbow extension.
What actions do muscles innervated by C8 have? (2)
- Grip. 2. Finger adduction and abduction.
What action do muscles innervated by T1 have?
None.
What muscles does the axillary nerve innervate? (2)
- Deltoid. 2. Teres minor.
What kind of joint is the sternoclavicular joint?
A synovial joint.
A dislocation near the sternoclavicular joint may cause a problem with what arteries and structure? (3)
The subclavian artery, trachea, and neck vasculature.
Is the scapulothoracic joint a true joint?
No.
What helps deepen the shoulder joint?
The glenoid labrum.
What ligament stabilizes the lateral elbow?
The radial collateral ligament.
What ligament stabilizes the medial elbow?
The ulnar collateral ligament.
What kind of joint is the elbow joint?
A hinge joint composed of humeroulnar and radioulnar joints.
What ligament holds the radius in place and keeps it close to the ulnar?
Annular ligament.
What ligament allows for supination and pronation?
Annular ligament.
Where does pronation and supination occur?
At the head of the radius.
What movements does the humeroulnar joint allow for? (3)
- Flexion. 2. Extension. 3. Circumduction.
What movements do the radioulnar joint allow for? (2)
- Pronation. 2. Supination.
Name the proximal carpal bones from medial to lateral (4).
- Scaphoid. 2. Lunate. 3. Triquetrum. 4. Pisiform.
Name the distal carpal bones from medial to lateral (4).
- Trapezium. 2. Trapezoid. 3. Capitate. 4. Hamate.
List the general bones of the hand from proximal to distal (3).
- Carpals. 2. Metacarpals. 3. Phalanges.
