Upper Limb Flashcards
1
Q
Brachial Plexus
A
- Network of nerve fibres that supply the skin and musculature of the upper limb.
- Location: Begins in the root of the neck, passes through the axilla, and enters the upper arm.
- Roots: C5-T1. Roots of the brachial plexus are formed by the anterior divisions of the spinal nerves.
2
Q
Dorsal Scapular Nerve
A
- Arises from brachial plexus
- Nerve Roots: C4-C5
- Location: Pierces middle scakene muscles and continues deep to levator scapulae and rhomboids
- Motor: Innervates rhomboid muscles (pulls scapula towards spine) and levator scapulae muscles (elevates scapula).
3
Q
Supra Scapular Nerve
A
- Arises from brachual plexus
- Nerve root: C5-C6
- Location: Wraps around scapula
- Motor Function: Supraspinatus and infrapinatus muscle
- Sensory function: Acromioclavicular joint and glenohumeral joint.
4
Q
Axillary Nerve
A
- Peripheral nerve of upper
- Nerve root: C5-C6
- Location: Formed with axilla region. It is a direct continuation of the posterior cord of the brachial plexus. It lies posteriorly to the axillary artery and anteriorly to the subscapularis muscle. It descends to inferior border of subscapularis muscle and then exits the axilla posteriorly via the quadrangular space. Axillary nerve terminates by dividing into 2 branches - posterior and terminal branch and anterior and terminal branch.
- Motor Function: Innervates teres minor and deltoid muscle
- Sensory Function: Sensory component is from the posterior termial branch were it continues as the upper lateral cutaneous nerve of the arm. It innervates skin of regimental badge area.
5
Q
Musculocutaneous nerve
A
- A major peripheral nerve of the upper limb.
- Nerve Root: C5-C7
- Location: Arises from lateral cord of brachial plexus. It then leaves the axilla and goes through the coracobrachalis muscle near its point of insertion on the humerus. it moves down the arm anterior to the brachialis muscle but deep to the biceps brachii.
- Motor Function: Innervates muscles in anterior compartment of the arm - biceps brachii, brachialis, coracobrachials.
- Sensory Function: Musculocutaneous nerve gives rise to laterla cutaneous nerve of forearm. Innervates the skin of the lateral aspect of the forearm.
6
Q
Long Thoracic Nerve
A
- Nerve root: C5-C7
- Location: DEscends through cervioaxillary canal behind the brachial plexus. Rests on outer surface of serratus anterior.
- Motor Function: Serratus anterior muscle.
7
Q
Anterior Thoracic Nerve
A
- Lateral - arises from brachial plexus
- Nerve Root: C5-C7
- Location: Passes across axillary artery and vein, pierces clavipectoral fossa, and is distributed to surface of pectoralis major muscle.
- Motor Function: Pectoralis Major
- Medial - arises from brachia plexus
- Nerve root: C6-C8
- Location: Passes behind axillary artery, curves forward between axillary artery and vein. Enters deep surface of pectoralis minor.
- Motor Function: Pectoralis major and pectoralis minor
8
Q
Median Nerve
A
- A major peripheral nerve of the upper limb
- Nerve Root: C6-T1
- Location: Derived from medial and lateral cords of the brachial plexus.
- After originating from brachial plexus in axilla the median nerve travels down the arm, initially lateral to brachial artery. Halfway down the arm, the nerve crosses over the brachial artery and becomes medially situated. It enters the anterior compartment of the forearm via cubital fossa, and gives rise to two major branches in the forearm:
- Anterior interosseous nerve -supplies deep muscles of anterior foreamr
- Palmar cutaneous nerve - innervates the skin of the lateral palm
- After originating from brachial plexus in axilla the median nerve travels down the arm, initially lateral to brachial artery. Halfway down the arm, the nerve crosses over the brachial artery and becomes medially situated. It enters the anterior compartment of the forearm via cubital fossa, and gives rise to two major branches in the forearm:
- Motor Function: Innervates majority of muscles in anterior forearm and some intrinsic hand muscles.
- Sensory Function:
- Palmar cutaneous branch: Innervates lateral aspect of the palm (does not pass through carpal tunnel).
- Palmar digital cutaneous branch: Innervates the palmar surface and fingertips of lateral 3.5 digits.
9
Q
Radial Nerve
A
- A major peripheral nerve of the upper limb
- Nerve Root: C5-T1
- Location: Arises in axilla, posteriorly to axillary artery. It exists axilla inferiorly and supplies braches into long and medial heads of the triceps brachii. Then travels down the arm in radial groove. Radial nerve enters forearm by moving anteriorly over laterla epicondyle of the humerus through the cubital fossa. It terminates by dividing into 2 braches - deep branch (motor) and superficial branch (sensory).
- Motor Function: Innervates muscles located in posterior upper arm and posterior forearm.
- Sensroy Function: There are 4 branches of the radial nerve provdie cutaneous innervation to the skin of the upper limb.
- Lower lateral cutaneous nerve of arm - Innervates lateral aspect of the upper arm, below deltoid.
- Posterior cutaneous nerve of arm - Innervates posterior surface upper arm
- Posterior cutaneous nerve of forearm - Innervates the strip of skin down the middle of the posterior forearm.
- Superifical branch - Terminal division of the radial nerve. It innervates the dorsal surface of the lateral 3.5 digits and associated palm area.
10
Q
Ulnar Nerve
A
- A major peripheral nerve of upper limb
- Nerve root: C8-T1
- Location: Derived from brachial plexus. it descends down medial side of the upper arm. At elbow it passes posterior to medial epicondyle of the humerus entering the foreamr. In the forearm it pierces 2 heads of flexor carpi ulnaris and travels along side of ulna. 3 branches arise in the forearm
- Muscular branch - innervates some muscles in anterior forearm
- Palmar cutaneous branch - Innervates skin in medial half of the palm.
- Dorsal cutaneous branch - Innervates skin of medial 1.5 fingers and associated palm area.
- Motor function: Innervates muscles in anterior compartment of forearm and hand
- Sensory function: 3 branches of ulnar nerve are responsible for cutaneous innervation
- Palmar cutaneous branch - innervates skin of medial half of palm.
- Dorsal cutaneous branch - Innervates skin of medial 1.5 fingers and dorsal hand area.
- Superficial branch - innervates the palmar surface of the medial 1.5 fingers.
11
Q
Bones in children vs. adults
A
- Main difference is that bones in children contain physis.
- Physis - trasulent, cartilaginous disc separating epiphysis from metaphysis. Responsible for long bone growth. Adds to risk of growth disturbance as it is weaker than bone.
12
Q
Parts of the Physis
A
- Zone of provisional calcification - Chondrocytes undergo apoptosis. Cartilagenous matric begins to calcify.
- Hypertrophic zone - Weakest zone. Lackes both collagen and calcified tissue. Chondrocytes stop mitosis and begin to hypertrophy.
- Proliferative zone - Chondrocytes undergo mitosis. Most metabolically active. Under influence of GH.
- Zone of reserve - Quiescent chondrocytes found.
13
Q
Pediatic vs. Adult Fractures
A
- Childrens bone have a stronger, more active periosterum covering the surface - allows for more radpid healing (Better O2 and nutrient supply to the bone).
- Increase potential for remodeling (depends on location) - There is risk of growth arrest/progressive deformity with a physeal injury.
- Bones in children are more likely to bend than break completely because they are softer and the periosteum is stronger and thicker - giver potential for incomplete fracture
- Greenstick fracture - A bend on one side and partia fracture on the other
- Torus/buckle fracture - One side of the bone bends, without breaking the other side.
14
Q
Salter-Harris Classification of Physeal Injuries
A
15
Q
Stages of fracture repair
A
20
Q
Compartments of the arm
A
21
Q
Compartments of Forearm
A
22
Q
Fracture description
A
