Exercise 15 Muscles of the Shoulder Arm Forearm and Hand

Page 1: Overview

  • Exercise 15 Muscles of the Shoulder, Arm, Forearm, and Hand.

Page 2: Views

  • Dorsal, Medial, Ventral views of the Shoulder, Arm, Forearm, and Hand Models.

Page 3: Anatomical Position

  • Dorsal, Medial, Ventral, Lateral views of Shoulder, Arm, Forearm, and Hand in Anatomical position.

Page 4: Muscles Acting on the Shoulder

  • Focus on Anterior Thoracic Group of muscles.

Page 5: Anterior Shoulder Muscles

  • Superficial Muscles:

    • Trapezius

    • Deltoid (cut)

    • Subclavius

    • Pectoralis Minor

    • Pectoralis Major (cut)

    • Deltoid (cut)

    • Teres Major

    • Serratus Anterior

    • Latissimus Dorsi

  • Deep Muscles:

    • Biceps Brachii (Long and Short Head)

    • Coracobrachialis

    • Anterior view of major shoulder muscles.

Page 9: Anterior Shoulder Muscle Table

  • Pectoralis Minor:

    • Action: Protracts and depresses scapula.

    • Origin: Ribs 3-5.

    • Insertion: Coracoid process of the scapula.

    • Innervation: Medial and lateral pectoral nerves.

  • Serratus Anterior:

    • Action: Rotates and stabilizes scapula during arm movements.

    • Origin: Ribs 1-8.

    • Insertion: Medial border of scapula.

    • Innervation: Long thoracic nerve.

  • Trapezius:

    • Origin: Superior nuchal line, nuchal ligament, spinous processes (C7-T3 or T4).

    • Action: Elevates, retracts, and depresses scapula.

    • Innervation: Accessory Nerve (Cranial Nerve XI).

    • Fiber Functions:

      • Superior: Elevate scapula.

      • Middle: Retract scapula.

      • Inferior: Depress scapula.

  • Levator Scapulae:

    • Origin: Transverse processes of C1-C4.

    • Insertion: Superior angle of scapula.

    • Function: Elevates scapula.

  • Rhomboids (Major and Minor):

    • Origin: Spinous processes T2-T5 (major) and C7-T1 (minor).

    • Insertion: Medial border of scapula.

    • Innervation: Posterior scapular nerve.

Page 10: Pectoralis Minor

  • Focused details on Pectoralis Minor's origins and insertions.

Page 12: Serratus Anterior

  • Detailed examination of Serratus Anterior's origin and insertions.

Page 16: Posterior Thoracic Group of Muscles

  • Superficial Group:

    • Trapezius

    • Levator Scapulae

    • Rhomboid muscles (Minor and Major)

    • Supraspinatus

    • Infraspinatus

  • Deep Group:

    • Teres minor and major

    • Latissimus dorsi

    • Other posterior muscles.

Page 18: Muscle Summary

  • Overview of Levator Scapulae, Deltoid, and Rhomboids (Major and Minor).

Page 22: Trapezius Origin and Insertion

  • Detailed overview of Trapezius muscle structures.

Page 28: Muscles Acting on the Arm

  • Overview of major arm muscles, including the Deltoid, Pectoralis Major, and others.

Page 31: Muscles Acting on the Arm Table

  • Pectoralis Major:

    • Action: Flexes, adducts, and medially rotates the humerus.

    • Origin: Medial clavicle and costal cartilages of ribs 2-6.

    • Insertion: Lateral intertubercular sulcus of humerus.

    • Innervation: Medial and lateral pectoral nerves.

  • Latissimus Dorsi:

    • Action: Adducts and medially rotates the humerus.

    • Origin: Vertebrae T7-L5, lower ribs, iliac crest.

    • Insertion: Intertubercular sulcus of the humerus.

    • Innervation: Thoracodorsal nerve (C6-C8).

    • Deltoid Functions:

      • Anterior fibers: Flex and medially rotate arm.

      • Middle fibers: Abduct arm.

      • Posterior fibers: Extend and laterally rotate arm.

Page 42: Latissimus Dorsi

  • Further examination of Latissimus Dorsi muscle structure.

Page 46: Muscle Atrophy

  • Muscle loss of 20-40% and its causes, emphasizing physical activity's importance.

Page 116: Muscles Acting on the Wrist and Hand

  • Overview of various wrist and hand muscles.

Page 117: Flexor and Extensor Overview

  • Functional grouping of muscles by actions at the wrist and hand.

Page 142: Intrinsic Muscles of the Hand

  • Overview of intrinsic muscles including Thenar, Hypothenar, Lumbricals, interosseous groups.

Page 146: Intrinsic Muscles Table

  • Summary of major functions, origins, and innervation.

  • Adductor Pollicis:

    • Draws thumb toward palm.

  • Hypothenar and Thenar Groups:

    • Functions related to the movement and positioning of fingers and thumb.

More detailed notes

Muscles of the Shoulder, Arm, Forearm, and Hand

Overview

This note covers the muscles of the shoulder, arm, forearm, and hand, detailing their actions, origins, insertions, and innervations.

Views

  • Dorsal View: Displays muscles as they appear from the back.

  • Medial View: Shows the inner side of the shoulder and arm.

  • Ventral View: Illustrates the muscles from the front perspective.

Anatomical Position

In the anatomical position, the body is upright, facing forward, with arms at the sides and palms facing forward. This position is crucial for anatomical terminology and descriptions.

  • Dorsal, Medial, Ventral, Lateral Views: Depict the shoulder, arm, forearm, and hand in this standardized position.

Muscles Acting on the Shoulder

Emphasizes the Anterior Thoracic Group of muscles:

  1. Pectoralis Major: Performs flexion, adduction, and medial rotation of the humerus.

  2. Pectoralis Minor: Protracts and depresses scapula.

  3. Serratus Anterior: Important for stabilizing and rotating the scapula during arm movements.

Anterior Shoulder Muscles

Superficial Muscles:

  • Trapezius: Elevates, retracts, and depresses the scapula.

  • Deltoid: Abducts, flexes, and extends the arm (with deeper layers visible after incision).

  • Subclavius: Stabilizes and depresses the clavicle.

  • Pectoralis Minor: Tag along with the Pectoralis Major, contributing to scapular movement.

  • Teres Major: Assists in adducting and medially rotating the arm.

  • Serratus Anterior: Key in arm elevation and stabilizing the scapula.

  • Latissimus Dorsi: Extends, adducts, and medially rotates the humerus.

Deep Muscles:

  • Biceps Brachii (Long and Short Head): Flexes elbow and supinates forearm.

  • Coracobrachialis: Flexes and adducts the arm.

Muscle Actions and Innervations

  1. Pectoralis Minor:

    • Action: Protracts and depresses scapula.

    • Origin: Ribs 3-5.

    • Insertion: Coracoid process of scapula.

    • Innervation: Medial and lateral pectoral nerves.

  2. Serratus Anterior:

    • Action: Rotates and stabilizes scapula during arm movements.

    • Origin: Ribs 1-8.

    • Insertion: Medial border of scapula.

    • Innervation: Long thoracic nerve.

  3. Trapezius:

    • Origin: Superior nuchal line, nuchal ligament, spinous processes (C7-T3 or T4).

    • Action: Elevates, retracts, and depresses scapula.

    • Innervation: Accessory Nerve (Cranial Nerve XI).

  4. Levator Scapulae:

    • Origin: Transverse processes of C1-C4.

    • Insertion: Superior angle of scapula.

    • Function: Elevates scapula.

  5. Rhomboids (Major and Minor):

    • Origin: Spinous processes (T2-T5 for Major and C7-T1 for Minor).

    • Insertion: Medial border of scapula.

    • Innervation: Posterior scapular nerve.

Posterior Thoracic Group of Muscles

Superficial Group:

  • Trapezius

  • Levator Scapulae

  • Rhomboid Muscles (Major and Minor)

  • Supraspinatus: Initiates arm abduction.

  • Infraspinatus: Laterally rotates the arm.

Deep Group:

  • Teres Minor: Assists in lateral rotation of the arm.

  • Latissimus Dorsi: A powerful extensor of the arm.

Muscle Summary

Provides an overview of the functions of the Levator Scapulae, Deltoid, and Rhomboids (Major and Minor), including specific actions in shoulder movements.

Trapezius Origin and Insertion

Detailed information on the Trapezius muscle's structure, actions, and functional significance in shoulder girdle movement.

Muscles Acting on the Arm

Covers major arm muscles: Deltoid, Pectoralis Major, and Latissimus Dorsi with an emphasis on their respective actions, origins, insertions, and innervations.

  • Deltoid Functions:

    • Anterior fibers: Flex and medially rotate arm.

    • Middle fibers: Abduct arm.

    • Posterior fibers: Extend and laterally rotate arm.

Muscle Atrophy

Discusses the muscle loss of 20-40%, its causes (like disuse or injury), and emphasizes the importance of physical activity in maintaining muscle mass.

Muscles Acting on the Wrist and Hand

Overview includes flexor and extensor muscles responsible for wrist and hand movements, crucial for fine motor skills.

Intrinsic Muscles of the Hand

Overview of key intrinsic muscle groups including Thenar, Hypothenar, Lumbricals, and Interosseous Groups with detail on their functions.

  • Adductor Pollicis: Draws the thumb toward the palm, essential for grip.

  • Hypothenar and Thenar Groups: Responsible for the fine movements and positioning of fingers and thumb.