DENT111 Anatomy: Upper Limb Muscles and Deltoid

DENT111 Anatomy

• Large muscles are detailed but smaller ones are not, shown as functions only
• Shoulder and arm muscles are detailed

Upper Limb Muscles

• Carpal tunnel syndrome is related to the median nerve

Shoulder and Arm Muscles

• A diagram of the main muscles of the shoulder and upper limb is presented, with front and back views.
• Specific muscles are labeled (e.g., Trapezius, Pectoralis major, Deltoid, Biceps, Triceps, etc.)
• Anatomical details of each muscle's location are shown for posterior view.
• Other descriptive anatomical parts (e.g., acromion, greater tubercle of humerus, deltoid muscle, etc.) are highlighted

Deltoid (M. Deltoideus)

• Has three parts: clavicularis, acromialis, spinalis
• Involved in abduction of the glenohumeral joint (up to 15 degrees)

Abductior of the glenohumeral joint

• glenohumeral joint detailed
• glenoid cavity
• head of humerus

Deltoid (M. Deltoideus)

• All fibers abduct the shoulder (glenohumeral joint)
• Anterior fibers flex, medially rotate, and horizontally adduct the shoulder
• Posterior fibers extend, laterally rotate, and horizontally abduct the shoulder

Trapezius

• Has three parts: pars superior, pars media, pars inferior
• Triangular shape
• Facilitates abduction of the arm above 90 degrees

Trapezius

• The trapezius muscle does not attach to the humerus.
• Origins (descending, transverse, and ascending parts) are detailed, identifying the relevant vertebrae.
• Insertions, innervations, and actions are specified for each part of the muscle.

Latissimus Dorsi

• The only upper limb muscle that's attached to the lumbar area.
• Extends, adducts, and medially rotates the shoulder

Teres Major

• The muscle's function in extending the shoulder, adducting it, and medially rotating it
• Location on the lateral side of the inferior angle and lower half of the scapula's lateral border
• Insertion point is the crest of the lesser tubercle of the humerus

Rotator Cuff Muscles

• Muscles include: Supraspinatus, Teres Minor, Infraspinatus, and Subscapularis.
• Subheadings describe functions of each.

Supraspinatus

• Function includes abduction of the shoulder, stabilizing the head of the humerus in the glenoid cavity
• Originating point is the supraspinous fossa of the scapula
• Insertion point is the greater tubercle of the humerus, and innervation from the suprascapular nerve

Teres Minor

• Functions include laterally rotating, adducting, extending, and horizontally abducting the shoulder and stabilizing the head of the humerus in the glenoid cavity.
• Originates from the superior half of the lateral border of the scapula
• Inserts into the greater tubercle of the humerus
• Innervation comes from axillary nerve

Infraspinatus

• Function includes laterally rotating, adducting, extending, and horizontally abducting the shoulder and stabilizes the head of the humerus in the glenoid cavity
• Originates from the infraspinatus fossa of the scapula
• Inserts into the greater tubercle of the humerus, and suprascapular nerve innervates it

Subscapularis

• Function is to medially rotate the shoulder and stabilize the humerus in the glenoid cavity
• Originates from the subscapular fossa of the scapula
• Inserts into the lesser tubercle of the humerus

Rhomboid Major and Minor

• Function is to retract scapula and rotate the glenoid cavity downward
• Origin from the vertebrae T2 to T5
• Insertion is the medial border, inferior angle and root of spine of scapula

Levator Scapulae

• Function including elevating the scapula, downward rotation, lateral flexion of neck, and rotation on the same side.
• Originating points are the transverse processes of the 1st-4th cervical vertebrae
• Insertion point is the upper portion of the medial border and superior angle of the scapula
• Innervation provided by dorsal scapular and cervical nerves

Serratus Anterior

• Function includes abduction of scapula (if scapula is fixed), depressing scapula, holding the medial border against the rib cage, and acting in forced inhalation

Pectoralis Major

• Function is adduction of shoulder, horizontally adduction of shoulder and medial rotation. Elevating thorax in forced inhalation, flexing and extending shoulder, and horizontally adducting.
• Origin is from the medial half of clavicle, sternum, and costal cartilage of ribs 1-6.
• Insertion is crest of greater tubercle of humerus

Pectoralis Minor

• Function is depressing scapula, abducting scapula, and tilting the scapula anteriorly if fixed, as well as assisting in forced inhalation.
• Origin is from the 3rd, 4th, and 5th ribs.
• Insertion is at the coracoid process of scapula

Subclavius

• Function is drawing the clavicle inferiorly and anteriorly and elevating the 1st rib, stabilizing the sternoclavicular joint.
• Origin is from the 1st rib and cartilage
• Insertion is the inferior lateral clavicle

Biceps Brachii

• Function is flexing the elbow and forearm, as well as flexing the shoulder
• Origin is the coracoid process (short head) and supraglenoid tubercle (long head) of scapula
• Insertion is the tuberosity of radius

Triceps Brachii

• Function is extending the elbow and extending and adducting the shoulder.
• Long head insertion: infraglenoid tubercle of scapula
• Short Head: lateral surface of proximal humerus
• Medical head: posterior surface of distal humerus
• Insertion point is the olecranon process of ulna

Coracobrachialis

• Function is flexing and adducting the shoulder.
• Origin is the coracoid process of the scapula
• Insertion is medial surface of mid-humeral shaft

Forearm and Arm Muscles

• Biceps brachii, Brachialis, Brachioradialis, Pronator teres, Palmaris longus, Flexor carpi ulnaris, and Supinator are listed.

Brachialis

• Function is flexing the elbow
• Origin is the distal half of the anterior surface of humerus
• Insertion is the tuberosity and coronoid process of ulna

Brachioradialis

• Function is flexing the elbow, assisting in pronation and supination of the forearm.
• Origin is the lateral supracondylar ridge of humerus
• Insertion is the styloid process of radius

Extensors of the Wrist and Fingers

• Extensor tendons of the wrist and finger muscles are illustrated and described, including extensor expansion tendons.

Extensor Carpi Radialis Longus and Brevis

• Function in extending and abducting the wrist, assisting in flexing the elbow.
• Origin is the lateral supracondylar ridge of humerus
• Insertion is base of 2nd (longus) and 3rd (brevis) metacarpals

Extensor Carpi Ulnaris

• Function is extending and adducting the wrist.
• Origin is the lateral epicondyle of the humerus
• Insertion is the base of the 5th metacarpal

Extensor Digitorum

• Function is extending the 2nd-5th fingers and assisting in extending the wrist.
• Origin is the lateral epicondyle of the humerus
• Insertion is the middle and distal phalanges of the 2nd-5th fingers

Anconeus

• Function is assisting in forearm extension, stabilizing the elbow joint.
• Origin is the lateral epicondyle of the humerus
• Insertion is the lateral surface of the olecranon

Extensor Indicis

• No description provided

Flexors of the Wrist and Fingers

• Pronator teres, flexor carpi radialis, Palmaris longus, and flexor carpi ulnaris are pictured.

Flexor Carpi Radialis

• Function is flexing and abducting the wrist, flexing the elbow.
• Common flexor tendon from medial epicondyle of humerus.
• Insertion is the base of 2nd and 3rd metacarpals

Palmaris Longus

• Function is tensed palmar fascia, flexing the wrist and elbow.
• Origin is the common flexor tendon from medial epicondyle
• Insertion is the flexor retinaculum and palmar aponeurosis

Flexor Carpi Ulnaris

• Function is flexing and adducting the wrist, assisting in flexing the elbow.
• Origin is the median epicondyle of humerus.
• Ulnar head insertion is posterior surface of the proximal half of ulnar shaft.
• Pisiform insertion is at the base of the fifth metacarpal.

Flexor Digitorum Superficialis

• Function in flexing the second through fifth fingers and flexing the wrist.
• Origin is from the medial epicondyle of the humerus, ulnar collateral ligament, coronoid process, and radius shaft
• Insertion is into the sides of the middle phalanges of the 2nd-5th fingers

Flexor Digitorum Profundus

• Function is flexing the second-fifth fingers, and assists in flexing the wrist.
• Origin from medial anterior ulnar surface
• Insertion point is into the bases of the distal phalanges of the 2nd-5th fingers.

Pronator Teres

• Function is pronating the forearm and assisting in flexing the elbow.
• Origin is from the medial epicondyle, common flexor tendon.
• Insertion is into the middle of the radius' lateral surface.

Pronator Quadratus

• Function is pronating the forearm.
• Origin is the medial anterior surface of distal ulna.
• Insertion is into the lateral anterior surface of distal radius.

Supinator

• Function is supinating the forearm
• Origin is from the radial collateral ligament, annular ligament, and the supinator crest of ulna
• Insertion is into the lateral surface of proximal radius shaft

Muscles of the Thumb and Hand

• A depiction and description of numerous muscles of the thumb and hand are shown.

Long Muscles of the Thumb

• No description provided

Abductor Pollicis Longus

• No description provided

Extensor Pollicis Longus and Brevis

• Extend the thumb, with longus extending the wrist

Flexor Pollicis Longus

• No description provided

Short Muscles of the Thumb

• No description provided

Abductor Pollicis Brevis

• Abduct the thumb

Flexor Pollicis Brevis

• Flexes the thumb

Opponens Pollicis

• Opposes the thumb

Adductor Pollicis

• Function is to adduct the thumb

Muscles of the Hand

• Numerous musculature drawings of the hand are shown and referenced.

Lumbricals of the Hand

• Four muscles are shown

Palmar Interossei

• No description provided

Dorsal Interossei

• Function in abducting fingers and acting on metacarpophalangeal joints

Abductor Digiti Minimi

• No description provided

Flexor Digiti Minimi Brevis

• Flexes the 5th finger

Opponens Digiti Minimi

• Opposes the 5th finger

Other Structures: Bursa

• Detailed image of bursae and associated ligaments of the shoulder region.

References

• Details about several anatomical reference texts are provided.

This quiz covers the anatomy of the upper limb muscles, focusing on the deltoid and its components. It includes detailed illustrations and the functions of important muscles like the trapezius, biceps, and triceps. Additionally, the relevance of carpal tunnel syndrome to the median nerve is discussed.