Pectoral Region Anatomy Lecture - Helwan National University - PDF

Faculty of Medicine Academic Year: 2024-2025 Year: 1 Semester: 2 Module: Locomotor system (lcs) 105 The Pectoral Region By: Dr. Eman Ahmed El Sawaf Department: Lecturer Of Anatomy And Embryology 2/6/2025 22  Objec...

Faculty of Medicine Academic Year: 2024-2025 Year: 1 Semester: 2 Module: Locomotor system (lcs) 105 The Pectoral Region By: Dr. Eman Ahmed El Sawaf Department: Lecturer Of Anatomy And Embryology 2/6/2025 22  Objectives By the end of this lecture student should be able to: Explain the anatomy of the pectoral region (Fascia – Muscles). 2/6/2025 LCS - 105 33  CONTENTS - Definition. - Contents: Superficial fascia. Deep fascia. Muscles: (Pectoralis major - Pectoralis minor - Subclavius). (origin - insertion - nerve supply - action). 2/6/2025 LCS - 105 4  Introduction Regions Of The Upper Limb Bones Of The Upper Limb 2/6/2025 LCS - 105 55  Definition Of The Pectoral Region It is the front of the upper part of the chest. 2/6/2025 LCS - 105 6  Contents (Layers) Of The Pectoral Region 1- Skin. 2-Superficial fascia (encloses the mammary glands and cutaneous vessels and nerves). 3-Deep fascia & Muscles. 2/6/2025 LCS - 105 7  Muscles Of The Pectoral Region - Pectoralis major. - Pectoralis minor. - Subclavius. - Origin. - Insertion. - Nerve supply. - Muscle action. 2/6/2025 LCS - 105 8  Muscles Of The Pectoral Region Pectoralis major 2/6/2025 LCS - 105 9  Muscles Of The Pectoral Region Pectoralis minor 2/6/2025 LCS - 105 10  Muscles Of The Pectoral Region Subclavius 2/6/2025 LCS - 105 11  Interactive Question Q- Mention the layers of the pectoral region. Q- Enumerate the muscles of the pectoral region. 2/6/2025 LCS- 105 12 12  Pectoralis Major Muscle The largest and the most superficial. 2/6/2025 LCS - 105 13  Pectoralis Major Muscle Origin 2/6/2025 LCS - 105 14  Pectoralis Major Muscle Origin Clavicular head: Anterior surface of medial half of clavicle. Sternocostal head: -Anterior surface of sternum. -Upper seven costal cartilages. 2/6/2025 LCS - 105 15  Pectoralis Major Muscle Insertion 2/6/2025 LCS - 105 16  Pectoralis Major Muscle Insertion Lateral lip of the bicipital groove (intertubercular sulcus ) of the humerus. 2/6/2025 LCS - 105 17  Pectoralis Major Muscle Origin Clavicular head: Anterior surface of medial half of Insertion clavicle. Lateral lip of Sternocostal head: the bicipital -Anterior surface groove of the of sternum. humerus. -Upper seven costal cartilages. 2/6/2025 LCS - 105 18  Pectoralis Major Muscle Nerve Supply Lateral pectoral nerve Pectoralis major Medial pectoral nerve 2/6/2025 LCS - 105 19  Pectoralis Major Muscle Muscle action The 2 heads acting together: Flexion, adduction and medial rotation of the arm at the shoulder joint. 2/6/2025 LCS - 105 20  Pectoralis Major Muscle Muscle action The 2 heads acting together: Flexion, adduction and medial rotation of the arm at the shoulder joint. 2/6/2025 LCS - 105 21  Pectoralis Minor Muscle -Small triangular muscle. -Lies deep to the pectoralis major. 2/6/2025 LCS - 105 22  Pectoralis Minor Muscle Insertion Origin 2/6/2025 LCS - 105 23  Pectoralis Minor Muscle Insertion Coracoid process of scapula (medial border and upper surface). Origin Ribs from 3 to 5 (anterior surfaces and superior borders). 2/6/2025 LCS - 105 24  Pectoralis Minor Muscle Insertion Coracoid process Origin of scapula Ribs from 3 to 5 (medial border and (anterior surfaces upper surface). and superior borders). 2/6/2025 LCS - 105 25  Pectoralis Minor Muscle Nerve Supply Medial pectoral nerve Pectoralis Minor 2/6/2025 LCS - 105 26  Pectoralis Minor Muscle Protracts the scapula Action Depresses the scapula (Drawing it anteriorly). (tip of the shoulder) (Drawing it inferiorly). 2/6/2025 LCS - 105 27  Pectoralis Minor Muscle Action Protracts and depresses the scapula. 2/6/2025 LCS - 105 28  Subclavius Muscle Small muscle lies deep to the pectoralis major muscle. 2/6/2025 LCS - 105 29  Subclavius Muscle Insertion Origin 2/6/2025 LCS - 105 30  Subclavius Muscle Insertion Subclavius groove. Origin From the first rib (at the junction between the rib and its costal cartilage). 2/6/2025 LCS - 105 31  Subclavius Muscle Insertion Subclavius groove. Origin From the first rib (at the junction between the rib and its costal cartilage). 2/6/2025 LCS - 105 32  Subclavius Muscle Nerve Supply Nerve to subclavius 2/6/2025 LCS - 105 33  Subclavius Muscle Action -Stabilizes the sternoclavicular Sterno joint. clavicular joint. -Depresses the clavicle. 2/6/2025 LCS - 105 34  Interactive Question Complete the following -The most superficial muscle in the pectoral region is ……….. -The pectoralis major is inserted into the ………………… -The pectoralis minor ………. and …………... the scapula. - The subclavius muscle is supplied by ………………….. 2/6/2025 LCS- 105 35 35  Deep fascia Pectoral fascia It is a thin lamina of connective tissue covering the surface of pectoralis major muscle. 2/6/2025 LCS - 105 36  Deep fascia Clavipectoral fascia -It is a thick sheet of connective tissue. - It connects the clavicle to the floor of the axilla (Suspensory Clavipectoral ligament of axilla). fascia Axilla 2/6/2025 LCS - 105 37  Deep fascia Clavipectoral fascia It encloses the subclavius (1) and pectoralis minor (2) muscles and covers the gap between them. 2/6/2025 LCS - 105 38  Deep fascia Clavipectoral fascia It is thickened at its upper border to form the costo-coracoid Costo-coracoid ligament (from the first ligament rib to the coracoid process). 2/6/2025 LCS - 105 39  Deep fascia Structures piercing the clavipectoral fascia Cephalic vein Thoraco - acromial artery Lateral pectoral nerve Lymphatics 2/6/2025 LCS - 105 40  Summary Pectoral region Superficial fascia Pectoral fascia Clavipectoral fascia Muscles 2/6/2025 LCS - 105 41 41  Summary Pectoralis major Pectoralis minor Subclavius Origin Clavicular head: - Ribs from 3 to 5 (anterior - From the first rib - Anterior surface of medial half of surfaces and superior borders). (at the junction between clavicle. the rib and its costal Sternocostal head: cartilage). - Anterior surface of sternum. - Upper seven costal cartilages. Insertion - Lateral lip of the bicipital groove of the - Coracoid process -Subclavius groove. humerus. of scapula (medial border and upper surface). Nerve - Lateral & Medial pectoral nerves. Medial pectoral nerve. - Nerve to subclavius. supply Muscle The 2 heads acting together: - Protracts the scapula. -Stabilizes the action - Flex, adduct and medially rotate the arm - Depresses the scapula. sternoclavicular joint. at the shoulder joint. (tip of the shoulder) -Depresses the clavicle. 2/6/2025 LCS - 105 42 42  Interactive Question MCQ Q-What is the nerve supply of pectoralis minor muscle? a. Medial pectoral. b. Lateral pectoral. c. Radial. d. Ulnar. Q-Which one of the following is the site of origin of subclavius muscle? a. Coracoid process. b. Sternum. c. First rib. d. Second rib. 2/6/2025 LCS- 105 43 43  References Gray's Anatomy for Students, 3rd Ed. With STUDENT CONSULT Online Access Drake, Vogl & Mitchell 2014. ISBN: 978-0-7020-5131-9 2/6/2025 LCS - 105 44 44  Thank You 2/6/2025 LCS - 105 45