Anatomy of Upper Limb Axilla & Its Contents PDF

Anatomy of Upper Limb Axilla & Its Contents By Dr. Hassan Mohammed Rizk (Ph.D.) Associate Professor of Human Anatomy and Embryology  Three Important Regions in Upper Limb UPPER LIMB Axilla and Its Contents By Dr. Hassan Rezk...

Anatomy of Upper Limb Axilla & Its Contents By Dr. Hassan Mohammed Rizk (Ph.D.) Associate Professor of Human Anatomy and Embryology  Three Important Regions in Upper Limb UPPER LIMB Axilla and Its Contents By Dr. Hassan Rezk August 29, 2024 2  Objectives: by the end of this lecture the student must understand the following knowledge: UPPER LIMB 1) Identify and demonstrate the Apex, Base & Walls (anterior, posterior, medial & lateral) of axilla. 2) Enumerate and demonstrate the contents of axilla. Axilla and Its Contents By Dr. Hassan Rezk August 29, 2024 3  Case Study UPPER LIMB Right Mastectomy Axilla and Its Contents By Dr. Hassan Rezk August 29, 2024 4  Introduction to Axilla (Axillary Fossa) (Armpit) UPPER LIMB The axilla is the gateway to the upper limb. Providing an area of transition between the neck and the arm. Axilla and Its Contents By Dr. Hassan Rezk August 29, 2024 5 UPPER LIMB Axilla and Its Contents By Dr. Hassan Rezk August 29, 2024 6 UPPER LIMB Axilla and Its Contents By Dr. Hassan Rezk August 29, 2024 7 UPPER LIMB Introduction to Axilla (Axillary Fossa) (Armpit) Axilla is Formed by the following: 1. Clavicle. 2. scapula,. 3. upper thoracic wall. 4. Humerus. 5. Related muscles. Axilla is an irregular 4-sided pyramidal space with: 1. Four sides (walls): Anterior, posterior, medial & lateral. 2. Inlet (Apex). 3. Floor (base) Axilla and Its Contents By Dr. Hassan Rezk August 29, 2024 8 UPPER LIMB Axilla Axilla and Its Contents By Dr. Hassan Rezk August 29, 2024 9  Objective # ( 1 ) Apex (Inlet) (Cervico-axillary Canal) The margins of the inlet are completely formed by bone: UPPER LIMB 1) Medial margin: is the lateral border of rib I. 2) Anterior margin: is the posterior surface of the clavicle. 3) Posterior margin: is the superior border of the scapula. Major vessels and nerves pass between the neck and the axilla by crossing over the lateral border of rib I and through the axillary inlet. 1) Subclavian artery. Superior View Of Right Axilla 2) Axillary vein. 3) Trunks of the brachial plexus. Axilla and Its Contents By Dr. Hassan Rezk August 29, 2024 10  Objective # ( 2 ) Base (Outlet) (Floor) UPPER LIMB The floor of the axilla is formed by: S P A 1) Fascia. I 2) Skin. Floor extends between anterior and posterior axillary folds. Axilla Anterior axillary fold: is formed by lower margin of pectoralis major muscle. Posterior axillary fold: is formed by teres major and latissimus dorsi muscles. Parasagittal View Of Right Axilla Axilla and Its Contents By Dr. Hassan Rezk August 29, 2024 11 UPPER LIMB Axilla Parasagittal View Of Right Axilla Axilla and Its Contents By Dr. Hassan Rezk August 29, 2024 12  Objective # ( 3 ) Anterior (Pectoral) Wall Clavipectoral fascia S The anterior wall of the axilla is formed by: P A UPPER LIMB 1) Skin. I 2) Superficial fascia. 3) Deep fascia. 4) Pectoralis major muscle. Axilla 5) Pectoralis minor. 6) Subclavius muscles. Parasagittal 7) Clavipectoral fascia View Of Right Axilla Axilla and Its Contents By Dr. Hassan Rezk August 29, 2024 13  Clavipectoral Fascia UPPER LIMB ▪ It is a thick sheet of connective tissue that connects the clavicle to the floor of the axilla (axillary fascia). ▪ It encloses the subclavius and pectoralis minor muscles and fills the gap between them. ▪ Structures passing through the clavipectoral: ▪ Structures that pass between the subclavius and pectoralis minor muscles include: 1. Cephalic vein. 2. Thoraco-acromial artery. 3. Lateral pectoral nerve. ▪ Structure leaves the axilla by passing through the fascia inferior to pectoralis minor muscle: Lateral thoracic artery. ▪ Structure leaves the axilla by penetrating directly through the pectoralis minor muscle: Medial pectoral nerve. Axilla and Its Contents By Dr. Hassan Rezk August 29, 2024 14  Clavipectoral fascia UPPER LIMB Lateral thoracic artery Axilla Anterior View Of Right Axilla Axillary fascia Parasagittal View Of Right Axilla Axilla and Its Contents By Dr. Hassan Rezk August 29, 2024 15  S Objective # ( 4 ) Posterior (Scapular) Wall P A I The posterior wall of the axilla is formed by: UPPER LIMB 1) Costal surface of the scapula. 2) Subscapularis muscle. 3) Distal parts of the latissimus dorsi 4) Teres major. Axilla 5) Proximal part of the long head of the triceps brachii. Long head of triceps brachii This wall contains the Gateway to the Parasagittal View Of Right Axilla posterior scapular region. Axilla and Its Contents By Dr. Hassan Rezk August 29, 2024 16  Objective # ( 5 ) Medial (Costal) Wall UPPER LIMB The medial wall of the axilla consists of 1) upper thoracic wall (the ribs and related intercostal tissues). 2) serratus anterior. 3) Long thoracic nerve. Anterior Side View Of Right Axilla View Of 4) Intercostobrachial nerve Right Axilla Axilla and Its Contents By Dr. Hassan Rezk August 29, 2024 17  Intercostobrachial nerve UPPER LIMB ▪ The only major structure that passes directly through the medial wall and into the axilla. ▪ This nerve is the lateral cutaneous branch of the second intercostal nerve (anterior ramus of T2). ▪ supplies skin on the upper posteromedial side of the arm, which is part of the T2 dermatome. Axilla and Its Contents By Dr. Hassan Rezk August 29, 2024 18  Objective # ( 6 ) Lateral (Humeral) Wall The lateral wall of the axilla is narrow and formed by UPPER LIMB 1) Intertubercular sulcus of the humerus. 2) Pectoralis major muscle of the anterior wall attaches to the lateral lip of the intertubercular sulcus. 3) Latissimus dorsi and teres major muscles of the posterior wall attaches to the floor and medial lip of the intertubercular sulcus. Anterior View Of Right Axilla Axilla and Its Contents By Dr. Hassan Rezk August 29, 2024 19  Objective # ( 7 ) Contents of Axilla (1) Axillary Fat (is the largest content) UPPER LIMB (2) Axillary tail (process) of mammary gland. (3) Axillary artery and its branches. M2-Respiration & Circulation (4) Axillary vein & its tributaries. M2-Respiration & Circulation (5) Axillary Lymph nodes. (6 groups) M1-Respiration & Circulation (6) Cords & Branches of Brachial plexus. M2-Cognition & Action Axilla and Its Contents By Dr. Hassan Rezk August 29, 2024 20 UPPER LIMB Axilla and Its Contents By Dr. Hassan Rezk August 29, 2024 21 UPPER LIMB Axilla and Its Contents By Dr. Hassan Rezk August 29, 2024 22 UPPER LIMB Axilla and Its Contents By Dr. Hassan Rezk August 29, 2024 23 UPPER LIMB Axilla and Its Contents By Dr. Hassan Rezk August 29, 2024 24  Clinical Correlation Thoracic outlet syndrome (TOS) ▪ Definition: compression of neurovascular structures (brachial plexus or the subclavian artery or vein) as they pass from the lower neck to the armpit. UPPER LIMB ▪ Causes: include trauma, tumors (Pancoast tumor), or the presence of a cervical rib. ▪ Clinical picture differs according to the structure compressed: 1) Neurogenic TOS: is the most common type and involves the compression of the brachial plexus leading to neck pain and numbness and tingling in the fingers. 2) Arterial TOS: involves compression of the subclavian artery and presents with pain, pallor coldness, and pulselessness in the affected arm, especially during overhead activities. Radial pulse intensity decreases when the patient's right arm is abducted and externally rotated. 3) Venous TOS: results in pain, cyanosis and swelling of the arm. ▪ Imaging techniques such as duplex sonography, X-ray, MRI, or electrodiagnostic testing are used to detect the cause of TOS. ▪ Surgical resection of the causal structures might become necessary in the case of progressive neurologic dysfunction or acute vascular insufficiency. Axilla and Its Contents By Dr. Hassan Rezk August 29, 2024 25 UPPER LIMB Axilla and Its Contents By Dr. Hassan Rezk August 29, 2024 26  Case Scenario A 31-year-old man comes to the physician because of a 1-month history of pain in his right arm and numbness and tingling in his right hand. One month ago, he quit his job as a UPPER LIMB painter because the symptoms worsened whenever he tried to reach above his head. He has no history of serious illness and takes no medications. He does not smoke and drinks two beers daily. Vital signs are within normal limits. Physical examination shows decreased sensation to fine touch in the 4th and 5th fingers of his right hand. Radial pulse intensity decreases when the patient's right arm is abducted and externally rotated. Which of the following is the most likely cause of this patient's symptoms? A. Carpal tunnel syndrome B. Cervical rib C. Polymyositis D. Upper trunk compression E. Cervical disc protrusion Axilla and Its Contents By Dr. Hassan Rezk August 29, 2024 27  Reference UPPER LIMB Gray's anatomy for students, 3rd edition. ISBN: 978-0-7020-5131-9 Copyright© 2015, 2010, 2005 by Churchill Livingstone, an imprint of Elsevier Inc. Chapter 7, pages 18 - 24 Axilla and Its Contents By Dr. Hassan Rezk August 29, 2024 28 UPPER LIMB Axilla and Its Contents By Dr. Hassan Rezk August 29, 2024 29