Introduction to Anatomy & Gross Anatomy-1 PDF

Introduction to Anatomy & Gross Anatomy of the Upper Limbs Course code: ANA 201 / 221 Session: 2019/2020 Dr Abayomi T.A & Dr Adegoke A.A Department of Anatomy, Faculty of Health Sciences, College of Health Sciences, Osun State University  Course Description History of Anatomy, Anatomi...

Introduction to Anatomy & Gross Anatomy of the Upper Limbs Course code: ANA 201 / 221 Session: 2019/2020 Dr Abayomi T.A & Dr Adegoke A.A Department of Anatomy, Faculty of Health Sciences, College of Health Sciences, Osun State University  Course Description History of Anatomy, Anatomical Terminology, General Organization of the Body Systems. Osteology of the upper limb, Pectoral region and mammary gland, shoulder girdle, axillae, brachial plexus, the arm, the elbow and the cubital fossa, anterior compartment of the forearm, posterior compartment of the forearm, the wrist and the hand, blood supply and lymph drainage of the upper limb, surface and radiological anatomy of the upper limb, nerve injuries of the upper limb.  Course objectives To understand the History and basic concepts of Anatomy To understand the general organisation of the human body To understand the osteology and muscular compartments of the upper limbs To understand the blood supply, innervation, lymphatics and dermatomes of the upper limbs To understand the joints associated with the upper limbs.  Course Schedule S/N Topic Week Format Lecturer 1 Introduction to Anatomy, History and anatomical terminologies Week 1 L ATA 2. General organization of body systems Week 2 L ATA 3. The Pectoral girdle (bones Week 3 L/P ATA and associated joints. Shoulder joint 4. Osteology of the upper limbs Week 4 AAA 5. Pectoral region- anterior and posterior thoracoappendicular muscles of the upper limbs Week 5 L/P AAA scapulohumeral muscles. The Anatomy of Breast-Blood supply, Venous drainage and lymph drainage 6. The Axilla and its content – axillary artery,axillary veins, axillary lymph nodes Week 6 L/P AAA 7. Brachial Plexus and brachial plexus injury Week 7 L/P ATA 8. CAT Week 7 9. Arm (Muscles, vascular supply and innervations) Week 8 L/P ATA 10. Elbow (joint and superior radio-ulna joint. Cubital fossa Week 9 L/P ATA 11 Forearm (Muscles, vascular supply and innervations). Week 10 L/P AAA 12. Wrist and Hand Week 11 L/P AAA 13 The blood supply and Anastomoses of the upper limb-Scapula, humerus, elbow and hand. Week 12 L/P AAA 14 Venous and lymphatic drainage of Upper Limb. Dermatomes of the Upper Limb Week 13 L/P AAA 15 Revision Week 13 L/P  Week 1: Introduction to Anatomy, History and anatomical terminologies Definition Anatomy is the study of the structure of the body. Human Anatomy studies the shape and structure of the human body, its origin, regularities of development in relation to its function and external environment. Conventional divisions Topographical or gross anatomy – surface, or ‘living', anatomy, – neuroanatomy, – endoscopic and imaging anatomy Microscopic anatomy or histology and Embryology (the study of the embryo and fetus).  Gross or macroscopic anatomy is the study of structures of the body that can be seen without using a microscopic. Microscopic anatomy, also called histology, is the study of cells and tissues using a microscope. Embryology is the study of the embryo and fetus.  Anatomy forms the basis for the practice of medicine. Anatomy leads the physician toward an understanding of a patient's disease The ability to interpret a clinical observation correctly is therefore the endpoint of a sound anatomical understanding.  Brief History of Anatomy The overall history of human anatomy can be divided into the following periods;  Greek period Greek period in the history of human anatomy started somewhere near 400 BC. The most famous anatomists of this period were Hippocrates and Herophilus. Hippocrates was regarded as the father of medicine and he was one of the founders of anatomy. Herophilus (about 304 B.C.), is known as father of anatomy and he was one of the first very few people to dissect human body. Herophilus did some great differentiations in the field of anatomy for example he differentiated cerebrum from cerebellum, nerves from tendons, arteries from veins etc.  Roman period Because human dissections were outlawed by the Romans, Claudius Galen (A.D. 130-201) wrote an anatomy textbook based on his dissections of the Barbary ape, a primate similar to man. His teachings were followed for nearly 15 centuries considering them as infallible authorities of anatomy. Though the text was helpful it had many inaccuracies.  Fourteenth century The most prominent scientist of this period was Mondino de Liuzzi. He was an Italian and had the post of professor of anatomy in Balogna. His famous book “Anthomia” was treated as the authorized anatomical text for over a century because he taught anatomy by dissection for which his book was a guide.  Fifteenth century During this century, Leonardo da Vinci (1452- 1519), the genius of Renaissance lived He was a painter, engineer, philosopher, and scientist in various fields of science, including anatomy. Da Vinci was the originator of cross sectional anatomy. The most admirable and important work done by him in the field of anatomy was the collection of drawings of the things he observed. These drawings were made with extreme perfection. He made a total of 500 diagrams in his 60 notebooks.  Sixteenth century The major advancements in the anatomy that occurred during the Renaissance were in large part due to the artistic and scientific ability of Andreas Vesalius (1514-1565). He is regarded as the “Founder of Modern Anatomy” because he made the world realize that anatomy can only be taught through dissection. Vesalius studied the structure of the human body systematically for the first time. He corrected the erroneous concepts of Galen and fought against his authority  Seventeenth century In this century lived the famous English anatomist William Harvey (1578-1657). He discovered the circulation of blood through human body and published in the book titled “Anatomical exercise on the motion of blood and heart in animals:” He also published a book on embryology.  Eighteenth and Nineteenth century In these two centuries major steps were taken in learning procedure for anatomy. Dissection was made compulsory for medical students. Warburton Anatomy Act was passed in England under which the unclaimed bodies were made available for dissection. The use of formalin as a fixative started in this period and techniques of endoscopy were also discovered. Prominent anatomists of this century included Cuvier, Meckel and Henry Gray (Author of Gray’s Anatomy).  ANATOMICAL TERMINOLOGY The names of all the consisting parts and organs of the human body were established at three Congresses in Basel, Jena and Paris. In 1895 the Basel Nomina Anatomica or BNA was introduced. In 1935 it was greatly changed at the Congress of Anatomists in Jena. In 1955 the IV-th International Federal Congress of Anatomists in Paris established new universal anatomical terms, the so-called Paris Nomina Anatomica, or PNA.  The Anatomical position The anatomical position is the standard reference position of the body used to describe the location of structures In the anatomical position, – the body is erect, – face looking forward – the feet are parallel to one another and flat on the floor, and – the arms are at the sides of the body with the palms of the hands turned forward.  Body regions and body cavities The human body is divided into regions and specific areas that are identified on the surface. The major body regions – head – neck – trunk Thorax Abdomen Pelvis & Perineum – upper extremity, and – lower extremity  Anatomical planes Three major groups of planes pass through the body in the anatomical position. Coronal planes are oriented vertically and divide the body into anterior and posterior parts. Sagittal planes also are oriented vertically, but are at right angles to the coronal planes and divide the body into right and left parts. The plane that passes through the center of the body dividing it into equal right and left halves is termed the median sagittal plane. Transverse, horizontal, or axial planes divide the body into superior and inferior parts. N/B Planes are imaginary flat surfaces that are used to divide the body or organs into definite areas  Planes of reference and axes  The axes of the human body The sagittal axis pierces the body from front to back. The frontal axis passes from the right side to the left. The vertical axis passes along the body of a man having vertical position. The longitudinal axis as well passes along the human body, but the position of the man does not matter; as well this axis passes along the limbs, organs etc. NB: The axes do not divide the human body into parts.  Terms to describe location Anterior (or ventral) and posterior (or dorsal) describe the position of structures relative to the "front" and "back" of the body. For example, the nose is an anterior (ventral) structure whereas the vertebral column is a posterior (dorsal) structure. Also, the nose is anterior to the ears and the vertebral column is posterior to the sternum. Medial and lateral describe the position of structures relative to the median sagittal plane and the sides of the body. For example, the thumb is lateral to the little finger. The nose is in the median sagittal plane and is medial to the eyes, which are in turn medial to the ears. Superior and inferior describe structures in reference to the vertical axis of the body. For example, the head is superior to the shoulders and the knee joint is inferior to the hip joint.  Proximal and distal are used with reference to being closer to or farther from a structure's origin, particularly in the limbs. For example, the hand is distal to the elbow joint. The glenohumeral joint is proximal to the elbow joint. These terms are also used to describe the relative positions of branches along the course of linear structures, such as airways, vessels, and nerves. For example, distal branches occur farther away toward the ends of the system, whereas proximal branches occur closer to and toward the origin of the system. Cranial (toward the head) and caudal (toward the tail) are sometimes used instead of superior and inferior, respectively. Rostral is used, particularly in the head, to describe the position of a structure with reference to the nose. For example, the forebrain is rostral to the hindbrain. Superficial and deep: These terms are used to describe the relative positions of two structures with respect to the surface of the body. For example, the sternum is superficial to the heart, and the stomach is deep to the abdominal wall.  Conventional vertical lines of the thorax On the both sides of the thorax on its anterior, lateral and posterior walls can be traced some vertical conventional lines. The anterior median line which passes through the middle side of the sternum. The posterior median line passes along the spinous processes of the thoracic vertebrae. The sternal line passes along the lateral border of the sternum. The medioclavicular line passes through the middle of the clavicle. The parasternal line passes on the middle distance between the sternal and medioclavicular lines. The anterior axillary line descends along the thorax from the anterior end of the anterior axillary fold. The middle axillary line comes downwards from the highest point of the axillary fossa. The posterior axillary line descends from the posterior end of the posterior axillary fold. The scapular line passes through the inferior angle of the scapula. The vertebral line comes downwards through the costo-transverse joints. The paravertebral line is situated on the middle distance between the vertebral and scapular lines. Week 2: General organization of body systems Cell Tissue Organs System Man  The cell Is the basic structural and functional units of the human body. There are many different types of cells (e.g., muscle, nerve, blood, etc). The human body consists of more than 75 trillion cells, each capable of growth, metabolism, response to stimuli, and, with some exceptions, reproduction. Although there are some 200 different types of cells in the body, these come together to form four basic tissues in the body.  Tissue Tissue is a group of cells that perform a specific function The four basic types of tissues in the human body – epithelial – muscle – nervous and – connective tissues  The epithelial tissue: cover the body’s surface and line the internal organs, body cavities, and passageways The muscular tissue: are capable of contraction and form the body’s musculature Nervous tissue: conduct electrical impulses and make up the nervous system Connective tissue: are composed of widely spaced cells and large amounts of intercellular matrix and which bind together various body structures  Organs an organ consists of 2 or more tissues that perform a particular function (e.g., heart, liver, stomach etc)  System Is an association of organs that have a common function The body systems are basically a collection of different organs that work together to perform specific functions in the body. 11 major systems in the human body, including digestive, nervous, endocrine, circulatory, respiratory, urinary, reproductive, muscular, lymphatic, skeletal, and integumentary.  Cardiovascular system Cardio –heart; vascular - vessels It consists of the heart (which pumps blood throughout the body) and blood vessels (which are a closed network of tubes that transport the blood). The three blood vessels are; – arteries, which transport blood away from the heart; – veins, which transport blood toward the heart; – Capillaries. These connect the arteries and veins, are the smallest of the blood vessels, and are where oxygen, nutrients, and wastes are exchanged within the tissues  Arteries are usually further subdivided into three classes, – Large elastic arteries contains large amount of elastc fibres in tunica media e.g are the aorta, the brachiocephalic trunk – Medium smooth arteries. Its tunica media contains mostly smooth muscle fibers. E.g femoral, axillary, and radial arteries artery, – Small arteries and arterioles empties into the cappilaries Veins are also subdivided into three, – Large veins. Thickest layer is the tunica externa e.g superior vena cava, the inferior vena cava, and the portal vein – Small and medium veins e.g superficial veins in the upper and lower limbs and deeper veins of the leg and forearm – Venules drain the capillaries  The nervous system Controls both voluntary action (like conscious movement) and involuntary actions (like breathing), and sends signals to different parts of the body Is divided based on structure and on function Structurally, it is divided into – the central nervous system (CNS) that comprise of the brain and spinal cord – the peripheral nervous system (PNS) is composed of all nervous structures outside the CNS that connect the CNS to the body Functionally, it is divided into – somatic part innervates structures (skin and most skeletal muscle) derived from somites in the embryo, and is mainly involved with receiving and responding to information from the external environment – visceral parts innervates organ systems in the body and other visceral elements, such as smooth muscle and glands, in peripheral regions of the body. It is concerned mainly with detecting and responding to information from the internal environment.  Skeletal system The skeleton can be divided into two subgroups, – the axial skeleton and – the appendicular skeleton. The axial skeleton consists of the bones of the skull (cranium), vertebral column, ribs, and sternum, whereas the appendicular skeleton consists of the bones of the upper and lower limbs. The skeletal system consists of cartilage and bone.  Cartilage is an avascular form of connective tissue consisting of extracellular fibers embedded in a matrix that contains cells localized in small cavities Consist of three types hyaline-most common; matrix contains a moderate amount of collagen fibers (e.g., articular surfaces of bones); elastic:-matrix contains collagen fibers along with a large number of elastic fibers (e.g., external ear); Fibrocartilage: matrix contains a limited number of cells and ground substance amidst a substantial amount of collagen fibers (e.g., intervertebral discs).  Bone is a calcified, living, connective tissue that forms the majority of the skeleton. Bones are vascular and are innervated. It consists of an intercellular calcified matrix, which also contains collagen fibers, and several types of cells within the matrix There are two types of bone, compact and spongy (trabecular or cancellous). Compact bone is dense bone that forms the outer shell of all bones and surrounds spongy bone. Spongy bone consists of spicules of bone enclosing cavities containing blood-forming cells (marrow). Classification of bones is by shape. Long bones are tubular (e.g., humerus in upper limb; femur in lower limb). Short bones are cuboidal (e.g., bones of the wrist and ankle). Flat bones consist of two compact bone plates separated by spongy bone (e.g., skull). Irregular bones are bones with various shapes (e.g., bones of the face). Sesamoid bones are round or oval bones that develop in tendons.  Digestive system consists of a series of connected organs that together, allow the body to break down and absorb food, and remove waste. It includes the mouth, esophagus, stomach, small intestine, large intestine, rectum, and anus. The liver and pancreas also play a role in the digestive system because they produce digestive juices.  Endocrine system consists of eight major glands that secrete hormones into the blood. These hormones, in turn, travel to different tissues and regulate various bodily functions, such as metabolism, growth and sexual function  Immune system is the body's defense against bacteria, viruses and other pathogens that may be harmful. It includes lymph nodes, the spleen, bone marrow, lymphocytes (including B-cells and T- cells), the thymus and leukocytes, which are white blood cells.  Muscular system The body's muscular system consists of about 650 muscles that aid in movement, blood flow and other bodily functions. There are three types of muscle: – skeletal muscle which is connected to bone and helps with voluntary movement – smooth muscle which is found inside organs and helps to move substances through organs – cardiac muscle which is found in the heart and helps pump blood.  Reproductive system The reproductive system allows humans to reproduce. The male reproductive system includes the penis and the testes, which produce sperm. The female reproductive system consists of the vagina, the uterus and the ovaries, which produce eggs.  Integumentary system The skin, or integumentary system, is the body's largest organ. It protects us from the outside world, and is our first defense against bacteria, viruses and other pathogens. Our skin also helps regulate body temperature and eliminate waste through perspiration. In addition to skin, the integumentary system includes hair and nails.  The urinary system Helps eliminate a waste product called urea from the body, which is produced when certain foods are broken down. The whole system includes two kidneys, two ureters, the bladder, two sphincter muscles and the urethra. Urine produced by the kidneys travels down the ureters to the bladder, and exits the body through the urethra.  Week 3: The Pectoral girdle (bones and associated joints. Shoulder joint The pectoral girdle (Shoulder girdle) serves as the point of attachment for the upper limbs. It is comprised of two bones, the clavicle and scapula. The bone that articulates with the pectoral girdle is called the humerus.  Clavicle The clavicle is a slender bone with an ‘S’ shape. Facing forward, the medial aspect is convex, and the lateral aspect concave. It extends between the sternum and the acromion of the scapula and can be palpated along its length. It can be divided into – a sternal end, – a shaft and – an acromial end.  The sternal end – contains a large facet – for articulation with the manubrium of the sternum at the sternoclavicular joint. – The inferior surface of the sternal end is marked by a rough oval depression for the costoclavicular ligament (a ligament of the SC joint).  The shaft of the clavicle acts as a point of origin and attachment for several muscles – deltoid, – trapezius, – subclavius, – pectoralis major, – sternocleidomastoid and sternohyoid  The acromial (lateral) end has a small facet for articulation with the acromion of the scapula at the acromioclavicular joint. It also gives attachment for two ligaments: – Conoid tubercle – attachment point of the conoid ligament, the medial part of the coracoclavicular ligament. – Trapezoid line – attachment point of the trapezoid ligament, the lateral part of the coracoclavicular ligament.  Clinical correlates The typical site of fracture is the middle third The medial and lateral thirds are rarely fractured. The acromial end of the clavicle tends to dislocate at the acromioclavicular joint with trauma  Scapula The scapula is a large, flat, triangular bone which lies on the posterolateral aspect of the chest wall, covering parts of the second to seventh ribs It has – three angles (lateral, superior, and inferior); – three borders (superior, lateral, and medial); – two surfaces (costal and posterior); and – three processes (acromion, spine, and coracoid process).  Angles The lateral angle of the scapula is marked by a shallow, glenoid cavity, which articulates with the head of the humerus to form the glenohumeral joint. The inferior angle lies over the seventh rib, or over the seventh intercostal space The superior angle is placed at the junction of the superior and medial borders.  Borders The lateral border of the scapula is strong and thick for muscle attachment, whereas The medial border and much of the superior border is thin and sharp. The superior border is marked on its lateral end by: – the coracoid process, a hook-like structure that projects anterolaterally and is positioned directly inferior to the lateral part of the clavicle; and – the small but distinct suprascapular notch, which lies immediately medial to the root of the coracoid process.  Surfaces The lateral surface of the scapula faces the humerus. It is the site of the glenohumeral joint, and of various muscle attachments. It is characterised by a shallow cavity, Glenoid fossa which articulates with the humerus to form the glenohumeral joint. A less distinct supraglenoid tubercle is located superior to the glenoid cavity and is the site of attachment for the long head of the biceps brachii muscle. A large triangular-shaped roughening (the infraglenoid tubercle) inferior to the glenoid cavity is the site of attachment for the long head of the triceps brachii muscle  The posterior surface of the scapula faces outwards. It is a site of attachment for the majority of the rotator cuff muscles of the shoulder. It is divided into a small, superior supraspinous fossa and a much larger, inferior infraspinous fossa by a prominent spine that runs transversely across the dorsal surface. The infraspinatus originates from the infraspinous fossa while the supraspinatus muscle originates from the supraspinous fossa.  The acromion, is an anterolateral projection of the spine, and it arches over the glenohumeral joint and articulates, via a small oval facet on its distal end, with the clavicle The region between the lateral angle of the scapula and the attachment of the spine to the posterior surface of the scapula is the greater scapular notch (spinoglenoid notch).  The costal surface of the scapula is characterized by a shallow concave subscapular fossa which provide attachment for the subscapularis The costal surface, together with the subscapularis move freely over the underlying thoracic wall  Joints The three joints in the shoulder complex are the – sternoclavicular, – acromioclavicular, and – glenohumeral joints The sternoclavicular joint and the acromioclavicular joint link the two bones of the pectoral girdle to each other and to the trunk. The glenohumeral joint is the articulation between the humerus of the arm and the scapula.  Sternoclavicular joint The sternoclavicular joint occurs between – the proximal end of the clavicle and – the clavicular notch of the manubrium of sternum together with a small part of the first costal cartilage. It is synovial and saddle-shaped. The articular cavity is completely separated into two compartments by an articular disc  Ligaments of SC The sternoclavicular joint is surrounded by a joint capsule and reinforced by four ligaments: – the anterior and posterior sternoclavicular ligaments are anterior and posterior, respectively, to the joint; – an interclavicular ligament links the ends of the two clavicles to each other and to the superior surface of the manubrium of sternum; – the costoclavicular ligament is positioned laterally to the joint and links the proximal end of the clavicle to the first rib and related costal cartilage.  Neurovasculature of SC joint Blood supply – internal thoracic arteries – suprascapular arteries The nerve supply – branches of the medial supraclavicular nerve – the nerve to the subclavius  Acromioclavicular joint Is a small synovial joint between an oval facet on the medial surface of the acromion and a similar facet on the acromial end of the clavicle Allows movement in the anteroposterior and vertical planes together with some axial rotation.  Ligaments of AC Joint The acromioclavicular joint is reinforced by: a small acromioclavicular ligament superior to the joint and passing between adjacent regions of the clavicle and acromion; and a much larger coracoclavicular ligament, which comprises – an anterior trapezoid ligament (which attaches to the trapezoid line on the clavicle) and – a posterior conoid ligament (which attaches to the related conoid tubercle).  Neurovasculature of AC Joint Blood supply – suprascapular arteries – thoracoacromial arteries Nerve supply – lateral pectoral – axillary nerves – subcutaneous lateral supraclavicular nerve (because of the subcutaneous location of the joint)  Glenohumeral joint is a synovial ball and socket articulation between the head of the humerus and the glenoid cavity of the scapula Joint is stabilized by the rotator cuff muscles (the supraspinatus, infraspinatus, teres minor, and subscapularis muscles), the long head of the biceps brachii muscle, related bony processes, and extracapsular ligaments. Movements at the joint include flexion, extension, abduction, adduction, medial rotation, lateral rotation, and circumduction  Glenoid labrum The articular surfaces of the glenohumeral joint is covered by hyaline cartilage The glenoid cavity is deepened and expanded peripherally by a fibrocartilaginous collar called the glenoid labrum, which attaches to the margin of the fossa. Superiorly, this labrum is continuous with the tendon of the long head of the biceps brachii muscle  Neurovascular supply of GH joint Vascular supply – branches of the anterior and posterior circumflex humeral – suprascapular arteries. Innervation is via branches from – the posterior cord of the brachial plexus, and – the suprascapular, axillary, and lateral pectoral nerves.  Glenohumeral ligaments consists of three bands, which runs with the joint capsule from the glenoid fossa to the anatomical neck of the humerus. They act to stabilize the anterior aspect of the joint. They are the – superior, – middle and – inferior glenohumeral ligaments.  The superior glenohumeral ligament passes from the supraglenoid tubercle, just anterior to the origin of the long head of biceps, to the humerus near the proximal tip of the lesser tubercle on the medial ridge of the intertuberculous groove, the fovea capitis The middle glenohumeral ligament arises from a wide attachment below the superior glenohumeral ligament, along the anterior glenoid margin as far as the inferior third of the rim, and passes obliquely inferolaterally, enlarging as it does, to attach to the lesser tubercle deep to the tendon of subscapularis, with which it blends. It provides anterior stability at 45° and 60° abduction The inferior glenohumeral ligament arises from the anterior, middle and posterior margins of the glenoid labrum, below the epiphysial line, and passes anteroinferiorly to the inferior and medial aspects of the neck of the humerus. The anterior band of the inferior glenohumeral ligament is thought to be the primary static anterior stabilizer of the abducted and externally rotated glenohumeral joint.  Coracohumeral ligament- attaches the base of the coracoid process to the greater tubercle of the humerus. It supports the superior part of the joint capsule Transverse humeral ligament- Spans the distance between the two tubercles of the humerus. It holds the tendon of the long head of the biceps in the intertubercular groove  Joint Capsule of GH joint Consist of loose fibrous membrane or sheath which encloses the structures of the joint. Is attached medially to the margin of the glenoid cavity and lateraly to the anatomical neck of the humerus. The fibrous layer of the joint capsule encloses the proximal attachment of the long head of the biceps brachii to the supraglenoid tubercle of scapula within the joint.  The inferior part of the joint capsule, the only part not reinforced by the rotator cuff muscles, is its weakest area. This part of the capsule is lax and lies in folds when the arm is adducted; however, it becomes taut when the arm is abducted.  The synovial membrane – lines the internal surface of the fibrous layer of the joint capsule and attaches to the margins of the articular surfaces. – It is loose inferiorly. This redundant region of synovial membrane and related fibrous membrane accommodates abduction of the arm. – forms a tubular shealth for the tendon of the long head of the biceps brachii, where it lies in the intertubercular groove of the humerus. – It produces synovial fluid to reduce friction between the articular surfaces  Bursa is a synovial fluid filled sac which acts as a cushion between tendons and other joint structures. Clinically important bursae are: Subacromial – located inferiorly to the deltoid and acromion, and superorly to the supraspinatus tendon and joint capsule of GH joint. – It supports the deltoid and supraspinatus muscles  Subscapular – located between the subscapularis tendon and the neck of the scapula. – It reduces wear and tear on the tendon during movement of the shoulder joint. Other bursae in this region are located: – Between the acromion and skin; – Between the coracoid process and the joint capsule Week 4: Osteology of the upper limbs.  Bones of the shoulder girdle: Clavicle and Scapula Bones of the arm: Humerus Bones of the Fore arm -ulna -radius Bones of the hand -carpal(8) -metacarpal(5) -phalanges(14) Clavicle Ventral view Dorsal view  Radius (arm) The shorter of the two long bones of the forearm, extending from the elbow to the wrist; it is the bone on the thumb side of The arm The radius rotates around the ulna, permitting The hand to rotate and be flexible. A projection just above the thumb side of the wrist marks the end of the radius.  Week 5: Pectoral Region. Breast PECTORAL REGION- Anterior and posterior thoracoappendicular muscles of the upper limbs scapulohumeral muscles. The Anatomy of Breast-Blood supply, Venous drainage and lymph drainage  Anterior and posterior thoraco(axio)appendicular muscles of the upper limbs scapulohumeral muscles Anterior Thoracoappendicular muscles Four anterior axioappendicular (thoracoappendicular or pectoral) muscles move the pectoral girdle: pectoralis major, pectoralis minor, subclavius, and serratus anterior. Posterior Thoracoappendicular muscles Superficial posterior axioappendicular (extrinsic shoulder) muscles: trapezius and latissimus dorsi. Deep posterior axioappendicular (extrinsic shoulder) muscles: levator scapulae and rhomboids. Scapulohumeral (intrinsic shoulder) muscles Scapulohumeral (Intrinsic Shoulder) Muscles The six scapulohumeral muscles (the deltoid, teres major, supraspinatus, infraspinatus, subscapularis, and teres minor) are relatively short muscles that pass from the scapula to the humerus and act on the glenohumeral joint.  Anterior Thoracoappendicular muscles MUSCLE ORIGIN INSERTION INNERVATION ACTION Clavicular Lateral and Adducts and head: anterior medial medially surface of pectoral rotates medial half of nerves; humerus; clavicle. clavicular draws Sternocostal Lateral lip of head (C5 and scapula Pectoralis head: anterior intertubercular C6), anteriorly and surface of groove of sternocostal inferiorly major sternum, humerus head (C7, Acting alone: superior C8, and T1) clavicular six costal head flexes cartilages, and humerus and aponeurosis of stemocostal external head oblique muscle extends it. 10/02/2014 3  Pectoralis major muscle 10/02/2014 4  MUSCLE ORIGIN INSERTION INNERVATION ACTION Medial border Medial pectoral Stabilizes and superior nerve scapula by surface of (C8 and T1) drawing it Pectoralis 3rd to 5th ribs coracoid process inferiorly and near of scapula anteriorly minor their costal against thoracic cartilages wall 10/02/2014 5  Pectoralis minor 10/02/2014 6  MUSCLE ORIGIN INSERTION INNERVATION ACTION Junction of 1st Inferior surface Nerve to Anchors and rib and of middle subclavius depresses its costal third of clavicle (C5 and C6) clavicle cartilage Subclavius External Anterior surface Long thoracic Protracts surfaces of of medial nerve scapula and Serratus lateral border of (C5, 66, and 07) holds anterior parts of 1st to scapula it against 8th ribs thoracic wall; rotates 10/02/2014 7  Serratus anterior and subclavius 10/02/2014 8 10/02/2014 9  Posterior Thoracoappendicular muscles The two most superficial muscles of the shoulder are the trapezius and deltoid muscles. Together, they provide the characteristic contour of the shoulder: Trapezius attaches the scapula and clavicle the trunk; Deltoid attaches the scapula and clavicle to the humerus. 10/02/2014 11 10/02/2014 12  Both trapezius and deltoid are attached to opposing surfaces and margins of the spine of the scapula, acromion, and clavicle. The scapula, acromion, and clavicle can be palpated between the attachments of trapezius and deltoid. 10/02/2014 13  Deep to trapezius the scapula is attached to the vertebral column by three muscles-levator scapulae, rhomboid minor and rhomboid major. These three muscles work with trapezius (and with muscles found anteriorly) to position the scapula on the trunk. 10/02/2014 14 MUSCLE ORIGIN INSERTION INNERVATION ACTION 1. Superior 1. Powerful nuchal line, 2. elevator of the external 1. Superior Motor spinal scapula; 2. occipital edge of the part of rotates the protuberance, crest of the accessory scapula during Trapezius 3. medial spine of the nerve (CN XI). abduction of margin of the scapula, 2. Sensory humerus above ligamentum acromion, 3. (proprioception horizontal; 3. nuchae, 4. posterior ) anterior rami middle fibers spinous border of of C3 and C4 retract scapula; processes of lateral one- 4. lower fibers CVII to TXII and third of clavicle depress 5. the related scapula supraspinous ligaments 10/02/2014 15 10/02/2014 16 MUSCLE ORIGIN INSERTION INNERVATION ACTION Major abductor of arm 1. Inferior edge (abducts arm Deltoid of the crest of beyond initial the spine of Deltoid 15° done by the scapula, 2. tuberosity of Axillary nerve supraspinatus); lateral margin humerus [C5,C6] clavicular fibers of the assist in flexing acromion, 3. the arm; anterior border posterior fibers of lateral one- assist in third of clavicle extending the arm 10/02/2014 17 MUSCLE ORIGIN INSERTION INNERVATION ACTION Transverse Posterior Branches Elevates the processes of CI surface of directly from scapula and CII medial border anterior rami of vertebrae and of scapula from C3 and C4 Levator posterior superior angle spinal nerves tubercles of to root of spine and by scapulae transverse of the scapula branches [C5] processes of from the dorsal CIII and CIV scapular nerve vertebrae 10/02/2014 18 MUSCLE ORIGIN INSERTION INNERVATION ACTION Lower end of Posterior ligamentum surface of Dorsal Rhomboi nuchae and medial border scapular Elevates and spinous of scapula at nerve [C4,C5] retracts the d minor processes of the root of scapula CVII and TI the spine of vertebrae the scapula 10/02/2014 19 MUSCLE ORIGIN INSERTION INNERVATION ACTION Posterior Spinous surface of Elevates and processes of TII- medial border Dorsal scapular retracts the Rhomboid TV vertebrae of scapula from nerve [C4,C5] scapula major and intervening the root of the supraspinous spine of the ligaments scapula to the inferior angle 10/02/2014 20 Scapulohumeral Muscles Muscles of Scapular region 1. Deltoideus Origin: lateral 1/3 of clavicle, acromion, spine of scapula Insertion: deltoid tuberosity of humerus Action: abduct arm to 90 c, medial & lateral rotate arm Nerve : axillary n. 2. TERES MINOR Origin: superior 2/3 lateral border, dorsal surface of scapular Insertion: inferior facet of greater tubercle of humerus Action: lateral rotation of arm Nerve: axillary nerve 3. SUBSCAPULARIS Origin: subscapular fossa Insertion: lesser tubercle of humerus Action: medially rotate arm Nerve: upper & lower subscapular nerves (C5,6) 4. TERES MAJOR Origin: inferior 1/3 lateral border of scapular Insertion: medial lip of bicipital groove Action: adduction & medial rotation of arm Nerve: lower subscapular nerve (branch of posterior cord) 5. SUPRASPINATUS Origin: supraspinus fossa Insertion: superior facet of greater tubercle of humerus Action: abduction of arm Nerve: suprascapular nerve 6. INFRASPINATUS Origin: infraspinus fossa Insertion: middle facet of greater tubercle of humerus Action: abduct & lateral rotate arm Nerve: suprascapular nerve Spaces of the scapular region  QUADRANGULAR SPACE Borders – medial: long head of triceps – lateral: humeral shaft – superior: teres minor – inferior: teres major Contents – axillary nerve passes through the quadrilateral space on its path to innervate the teres minor and deltoid and provide sensation to the lateral arm posterior humeral circumflex artery  TRIANGULAR SPACE Borders – inferior: teres major – lateral: long head of triceps – superior: lower border of teres minor Contents scapular circumflex artery  TRIANGULAR INTERVAL Borders – superior: teres major – lateral: lateral head of the triceps or the humerus – medial: long head of the triceps Contents – profunda brachii artery radial nerve  Clinical Relevance 1. Chest wall – heart /lung sound 2.Clavipectoral fascia - protection of the vessels and nerves underneath -limit spreading of the abscess from upper limb to the neck 3. Fracture of clavicle - common site is at 1/3 from the lateral 4. Breast cancer - structural abnormality - lymphatic drainage & metastasis - mastectomy -Blood supply to the pectoral region 1. Axillary artery 2. Perforating branches of the internal thoracic a. 1. Axillary artery : divided into 3 parts First part : Supreme thoracic a. Second part : 1.Thoraco-acromial trunk Acromial branch Pectoral branch Clavicular branch Deltoid branch 2. Lateral thoracic a. Third part : give branches to supply head of humerus and scapular regions Venous drainage at the pectoral region 1. Deep veins - axillary v. internal thoracic v. and lateral thoracic v.  TRIANGULAR INTERVAL Borders – superior: teres major – lateral: lateral head of the triceps or the humerus – medial: long head of the triceps Contents – profunda brachii artery radial nerve  Clinical Relevance 1. Chest wall – heart /lung sound 2.Clavipectoral fascia - protection of the vessels and nerves underneath -limit spreading of the abscess from upper limb to the neck 3. Fracture of clavicle - common site is at 1/3 from the lateral 4. Breast cancer - structural abnormality - lymphatic drainage & metastasis - mastectomy -Blood supply to the pectoral region 1. Axillary artery 2. Perforating branches of the internal thoracic a. 1. Axillary artery : divided into 3 parts First part : Supreme thoracic a. Second part : 1.Thoraco-acromial trunk Acromial branch Pectoral branch Clavicular branch Deltoid branch 2. Lateral thoracic a. Third part : give branches to supply head of humerus and scapular regions Venous drainage at the pectoral region 1. Deep veins - axillary v. internal thoracic v. and lateral thoracic v.  Anatomy of The Breast Breast is a derivative of skin Breast : nipple, areolar, mammary gland (F) 1. Surface Anatomy (position) : Nipple – 4-5” from the midline, intercostal space 4 Breast – between rib 2-7 2. Components : - subcutaneous fat, mammary gland - Lactiferous duct - Cooper’s ligament (suspensory ligament) - Retinaculum cutis fascia  The majority of the breast is in the superficial fascia, except the tail part (Tail of Spence) extends upward laterally into deep fascia at the lower border of pectoralis major. 2/3 of the gland lies on pectoralis major 1/3 of the gland lies on serratus anterior  Lymphatic drainage of the breast 1. Superficial - around the mammary gland, lymphatic network is highly anastomosed / drainage is parallel the venous drainage. 2. Deep - lymph nodes are formed along the lymphatic vessels. A. from lateral side of the breast, drains into the anterior group of the axillary lymph node (the pectoral node). B. from medial side of the breast, drains into the parasternal node (the internal thoracic node)  Week 6: The Axilla and its content The Axilla is a pyramid-shaped space between the upper part of the arm and the side of the chest through which major neurovascular structures pass between neck & thorax and upper limbs. Axilla has an apex, a base and four walls. Boundaries of the Axilla  Apex: C 1 L  Is directed upwards into A R the root of the neck. I B  is bounded, by 3 bones: V I Clavicle anteriorly. C L E Upper border of the scapula posteriorly. Outer border of the first rib medially. It is called cervico- axillary canal.  Base:  Formed by skin stretching between the anterior and posterior walls.  is bounded: In front by the anterior axillary fold (formed by the lower border of the Pectoralis major muscle). Behind by the posterior axillary fold (formed by the tendons of latissimus dorsi and teres major muscle). Medially by upper 4 to 5 ribs & the chest wall.  Anterior wall:  Is formed by Clavipectoral fascia Pectoralis major Pectoralis minor Subclavius Clavipectoral fascia: Pectoralis minor Pectoralis major  Posterior wall: Is formed by: Subscapularis. Latissimus dorsi. Teres major muscles.  The medial wall:  Is formed by: Serratus anterior Upper 4-5 ribs & Intercostal muscles.  The lateral wall:  Is formed by: Coracobrachi- alis. Biceps brachii. Intertubercular groove of the humerus.  Contents of The Axillary a. & v. Axilla Cords and braches of brachial plexus. Axillary artery and its branches. Axillary vein and its tributaries. Axillary lymph nodes. Axillary fat. Brachial Loose connective plexus tissue. The neurovascular bundle is enclosed in connective tissue sheath, called ‘axillary sheath’ Axillary artery : divided into 3 parts First part : Supreme thoracic a. Second part : 1.Thoraco-acromial trunk Acromial branch Pectoral branch Clavicular branch Deltoid branch 2. Lateral thoracic a. Third part : give branches to supply head of humerus and scapular regions -subscapular artery -ant. Circumflex humeral aretry -pot. Circumflex humeral artery AXILLARY VEIN It accompanies axillary arterythrough the axilla. Formed at the lower border of the teres majorby joining together of the venae commitantes of brachial artery and basilic vein Ends at outer border of the first rib by becoming the subclavian vein It receives cephalic vein and veins accompanying branches of axillary artery It lies medial to axillary arteryseparated bymedial cord of brachial plexus, medial pectoral nerve, ulnar and and medial cutaneous nerve of forearm. Axillary lymph nodes These are divided into following five groups -lateral group(along axillary vein) Anterior or pectoral group(along lower border of pectoralis major) Posterior or subscapular group(along the course of subscapular vessels) Central group(in fat central to axilla) Apical group(it lies near apex of axilla)  Applied anatomy Paralysis of root and cords of BP Breast cancer Referred heart pain Retromammary bursa Anaesthetics in upper limb surgery Week 7: Brachial Plexus and brachial plexus injury The brachial plexus is a somatic plexus formed by the anterior rami of C5 to C8, and most of the anterior ramus of T1. It originates in the neck, passes laterally and inferiorly over rib I, to enter the axilla. The parts of the brachial plexus, from medial to lateral, are roots, trunks, divisions, and cords. All major nerves that innervate the upper limb originate from the brachial plexus, mostly from the cords.  Parts of Brachial Plexus The parts of the brachial plexus, from medial to lateral, are: – Roots – Trunks – Divisions – Cords  Roots The roots of the brachial plexus are the anterior rami of C5 to C8, and most of T1. Close to their origin, the roots receive gray rami communicantes from the sympathetic trunk The roots and trunks passes between the anterior scalene and middle scalene muscles to enter the posterior triangle of the neck To lie superior and posterior to the subclavian artery.  Trunks The brachial plexus consist of three trunks which originate from the roots, pass laterally over rib I, and enter the axilla The superior trunk is formed by the union of C5 and C6 roots The middle trunk is a continuation of the C7 root The inferior trunk is formed by the union of the C8 and T1 roots. The inferior trunk lies on rib I posterior to the subclavian artery; the middle and superior trunks are more superior in position.  Divisions Each of the three trunks of the brachial plexus divides into an anterior and a posterior division The three anterior divisions forms part of BP that gives rise to peripheral nerves associated with the anterior compartments of the arm and forearm; The three posterior divisions gives rise to nerves associated with the posterior compartments of the arm and forearm No peripheral nerves originate directly from the divisions of the brachial plexus  Cords The three cords of the BP originate from the divisions and are related to the second part of the axillary artery Lateral cord – is formed from the union of the anterior divisions of the upper and middle trunks – Has contributions from C5 to C7 – it lies lateral to the second part of the axillary artery Medial cord – is the continuation of the anterior division of the inferior trunk- it contains contributions from C8 and T1 – is medial to the second part of the axillary artery Posterior cord – formed as the union of all three posterior divisions – it contains contributions from all roots of the brachial plexus (C5 to T1). – occurs posterior to the second part of the axillary artery  Most of the major peripheral nerves of the upper limb originate from the cords of the brachial plexus. Generally, nerves associated with the anterior compartments of the upper limb arise from the medial and lateral cords and nerves associated with the posterior compartments originate from the posterior cord.  Branches Branches of the roots In addition to small segmental branches from C5 to C8 to muscles of the neck and a contribution of C5 to the phrenic nerve, the roots of the brachial plexus give rise to two branches; The dorsal scapular nerve: – originates from the C5 root of the brachial plexus; – passes posteriorly towards the medial border of the scapula and – innervates the rhomboid major and minor muscles from their deep surfaces The long thoracic nerve: – originates from the anterior rami of C5 to C7; – passes vertically down the medial wall of the axilla to supply the serratus anterior muscle – lies on the superficial aspect of the serratus anterior muscle. Branches of the trunks The suprascapular nerve (C5 and C6): – originates from the superior trunk of the brachial plexus; – enters the posterior scapular region – innervates the supraspinatus and infraspinatus muscles; and – is accompanied in the lateral parts of the neck and in the posterior scapular region by the suprascapular artery. The nerve to subclavius muscle (C5 and C6) is a small nerve that: – originates from the superior trunk of the brachial plexus; – passes anteroinferiorly over the subclavian artery and vein – innervates the subclavius muscle Branches of the lateral cord : consist of three branches Lateral pectoral nerve – is the most proximal of the branches from the lateral cord. – It penetrate the clavipectoral fascia – and innervates the pectoralis major muscle. Musculocutaneous nerve – is a large terminal branch of the lateral cord. – It passes laterally to penetrate the coracobrachialis muscle and pass between the biceps brachii and brachialis muscles in the arm – innervates all three flexor muscles in the anterior compartment of the arm, terminating as the lateral cutaneous nerve of forearm. Lateral root of median nerve – is the largest terminal branch of the lateral cord – passes medially to join a similar branch from the medial cord to form the median nerve Branches of the medial cord. It consist of five branches. Medial pectoral nerve – is the most proximal branch. It receives a communicating branch from the lateral pectoral nerve – Branches of the nerve penetrate and supply the pectoralis minor muscle as well as the pectoralis major muscle. Medial cutaneous nerve of arm (medial brachial cutaneous nerve) – In the axilla, the nerve communicates with the intercostobrachial nerve of T2. – innervate the upper part of the medial surface of the arm and floor of the axilla.  Medial cutaneous nerve of forearm (medial antebrachial cutaneous nerve) – originates just distal to the origin of the medial cutaneous nerve of arm. – It innervates skin over the medial surface of the forearm down to the wrist. Medial root of median nerve – passes laterally to join with a similar root from the lateral cord to form the median nerve anterior to the third part of the axillary artery. Ulnar nerve – is a large terminal branch of the medial cord. – passes through the arm and forearm into the hand where it innervates all intrinsic muscles of the hand (except for the three thenar muscles and the two lateral lumbrical muscles). – In the forearm, branches of the ulnar nerve innervate the flexor carpi ulnaris muscle and the medial half of the flexor digitorum profundus muscle. – The ulnar nerve innervates skin over the palmar surface of the little finger, medial half of the ring finger, and associated palm and wrist, and the skin over the dorsal surface of the medial part of the hand Median nerve The median nerve is formed anterior to the third part of the axillary artery by the union of lateral and medial roots originating from the lateral and medial cords of the brachial plexus. It passes through the arm (anterior to the brachial artery) into the forearm where branches innervate most of the muscles in the anterior compartment of the forearm (except for the flexor carpi ulnaris muscle and the medial half of the flexor digitorum profundus muscle, which are innervated by the ulnar nerve). The median nerve continues into the hand to innervate: – the three thenar muscles associated with the thumb; – the two lateral lumbrical muscles associated with movement of the index and middle fingers; and – the skin over the palmar surface of the lateral three and one-half digits and over the lateral side of the palm and middle of the wrist. The musculocutaneous nerve, the lateral root of the median nerve, the median nerve, the medial root of the median nerve, and the ulnar nerve form an M over the third part of the axillary artery Branches of the posterior cord. It consist of five nerves Superior subscapular nerve innervates the subscapularis muscle Thoracodorsal nerve innervates the latissimus dorsi muscle muscle Inferior subscapular nerve innervates the subscapularis and teres major muscle Axillary nerve innervates the deltoid and teres minor muscles. Radial nerve – is the largest terminal branch of the posterior cord – It passes out of the axilla and into the posterior compartment of the arm – It is accompanied through the triangular interval by the profunda brachii artery, which originates from the brachial artery in the anterior compartment of the arm. – The radial nerve and its branches innervate: all muscles in the posterior compartments of the arm and forearm; and the skin on the posterior aspect of the arm and forearm, the lower lateral surface of the arm, and the dorsal lateral surface of the hand.  WEEK 8 MID SEMESTER CONTINOUS ASSESSMENT TEST  Week 9: Arm Introduction The arm is the region of the upper limb between the shoulder and the elbow It is divided into two compartments (anterior and posterior) by medial and lateral intermuscular septa.  Anterior compartment The anterior compartment – Has three muscles (biceps brachii, brachialis and coracobrachialis muscles (BBC)) – are innervated predominantly by the musculocutaneous nerve – Arterial supply to the anterior compartment of the upper arm is via muscular branches of the brachial artery. – predominantly flex the elbow joint;  Biceps brachii Origin: The biceps brachii muscle has two heads: – the short head of the muscle originates from the coracoid process the scapula in conjunction with the coracobrachialis; – the long head originates as a tendon from the supraglenoid tubercle of the scapula Insertion: Both heads insert distally into the radial tuberosity and the fascia of the forearm via the bicipital aponeurosis (roof of the cubital fossa).  Action: – powerful flexor of the forearm at the elbow joint; – it is also the most powerful supinator of the forearm when the elbow joint is flexed Innervation: Musculocutaneous nerve. A tap on the tendon of biceps brachii at the elbow is used to test predominantly spinal cord segment C6  Coracobrachialis muscle Attachments: – Originates from the coracoid process of the scapula. – passes through the axilla, and – attaches the medial side of the humeral shaft, at the level of the deltoid tubercle. Action: Flexion of the arm at the shoulder, and weak adduction. Innervation: Musculocutaneous nerve.  Brachialis The muscle lies deep to the biceps brachii, is found more distally than the other muscles of the arm. It forms the floor of the cubital fossa. Attachments: Originates from the medial and lateral surfaces of the humeral shaft and inserts into the ulna tuberosity, just distal to the elbow joint. Action: Flexion at the elbow. Innervation: Musculocutaneous nerve, with contributions from the radial nerve.  Posterior compartment The posterior compartment – contains one muscle (triceps brachii muscle) – innervated by the radial nerve – extend the joint The posterior compartment of the upper arm – contains the triceps brachii muscle, which has three heads. – The medial head lies deeper than the other two, which cover it. Arterial supply to the posterior compartment of the upper arm is via the profunda brachii artery.  Triceps brachial Attachments: – Long head – originates from the infraglenoid tubercle. – Lateral head – originates from the humerus, superior to the radial grove. – Medial head – originates from the humerus, inferior to the radial groove. Distally, the heads converge onto one tendon and insert into the olecranon of the ulna. Action: Extension of the arm at the elbow. Innervation: Radial nerve. A tap on the triceps tendon tests spinal segment C7. Week 10: Elbow and Cubital fossa ELBOW  Introduction The elbow is the joint connecting the proper arm to the forearm. It is marked on the upper limb by the medial and lateral epicondyles, and the olecranon process. Structurally, the joint is classified as a synovial joint, and functionally as a hinge joint.  Articular surfaces It consists of three separate articulations: 1. Trochlear notch of the ulna and the trochlea of the humerus (Humeroulnar joint) 2. Head of the radius and the capitulum of the humerus (Humeroradial joint) (Humeroulnar joint and Humeroradial joint are involved in hinge-like flexion and extension of the forearm on the arm and, together, are the principal articulations of the elbow joint) 3. Head of the radius and the radial notch of the ulna, which forms the proximal radio-ulnar joint. (pronation and supination of the forearm). The articular surfaces of the bones are covered with hyaline cartilage  Joint capsule of elbow joint The fibrous membrane of the joint capsule overlies the synovial membrane Surrounds the elbow joint. It is attached to the humerus at the margins of the lateral and medial ends of the articular surfaces of the capitulum and trochlea. Anteriorly and posteriorly it is carried superiorly, proximal to the coronoid and olecranon fossa The fibrous membrane of the joint capsule is thickened medially and laterally to form collateral ligaments, which support the flexion and extension movements of the elbow joint The synovial membrane Lines the internal surface of the fibrous layer of the capsule and the intracapsular non-articular parts of the humerus. It is also continuous inferiorly with the synovial membrane of the proximal radioulnar joint. The joint capsule is weak anteriorly and posteriorly but is strengthened on each side by collateral ligaments  The synovial membrane is separated from the fibrous membrane of the joint capsule by pads of fat in regions overlying the coronoid fossa, the olecranon fossa, and the radial fossa. These fat pads accommodate the related bony processes during extension and flexion of the elbow  Ligaments of the elbow joint The major ligaments of the elbow joint include: Radial collateral ligament Medial collateral ligament Annular ligament  Radial collateral ligament This lateral, fan-like radial collateral ligament extends from the lateral epicondyle of the humerus and blends distally with the anular ligament of the radius Resists varus stress Maintains relationship between humeral and radial head  Ulnar collateral ligament The medial, triangular ulnar collateral ligament extends from the medial epicondyle of the humerus to the coronoid process and olecranon of the ulna It consists of three bands: (1) the anterior cord-like band is the strongest, (2) the posterior fan-like band is the weakest, and (3) the slender oblique band deepens the socket for the trochlea of the humerus  Anular ligament Anular ligament of the radius encircles and holds the head of the radius in the radial notch of the ulna, forming the proximal radioulnar joint and permitting pronation and supination of the forearm. Permits rotation of radius/ulna Attaches to anterior & posterior rims of the radial notch of the ulna Serves as attachment to radial collateral ligament Proximally blends with the elbow capsules  Vascular supply and innervation Vascular supply to the elbow joint is through an anastomotic network of vessels derived from collateral and recurrent branches of the brachial, profunda brachii, radial, and ulnar arteries. Innervation is predominantly by branches of the radial and musculocutaneous nerves, but there may be some innervation by branches of the ulnar and median nerves.  CUBITAL FOSSA The cubital fossa is an important area of transition between the arm and the forearm. It is a triangular depression located anterior to the elbow joint It is the site of venepuncture Boundary  Floor and Roof The floor of the cubital fossa is formed by the brachialis and supinator muscles of the arm and forearm, respectively The roof of the cubital fossa is formed by the continuity of brachial and antebrachial (deep) fascia reinforced by the bicipital aponeurosis, subcutaneous tissue, and skin. Contents of cubital fossa Deep contents: Lateral to medial Radial nerve, deep between the muscles forming lateral boundary of the fossa. Biceps brachii tendon Terminal part of the brachial artery and the commencement of its terminal branches, the radial and ulnar arteries. Median nerve. Superficial contents: the median cubital vein, lying anterior to the brachial artery, and the medial and lateral antebrachial cutaneous nerves, related to the basilic and cephalic veins. Note: The ulnar nerve does not pass through the cubital fossa. Instead, it passes posterior to the medial epicondyle  Week 11: Forearm Bones of the forearm The radius proximally articulates with the Humerus humerus at the elbow joint. Distally it articulates with the scaphoid and lunate Head bones of the carpus, and with the ulna at Tuberosity the distal radioulnar joint. of radius Interosseous Ulna The ulna is the more medial of the two bones. Its proximal end articulates with membrane the humerus at the elbow joint. Distally it Radius articulates with the radius. It is excluded from the wrist joint by the articular disc. Head The interosseous membrane bind the radius and the ulna together. Fig 1. Anterior view of bones of the forearm.  Superficial muscles of the anterior compartment. The superficial muscles of the anterior 1 compartment include pronator teres, flexor carpi radialis, palmaris longus, and flexor carpi ulnaris. 2 Also included in this group is flexor digitorum superficialis. The superficial group of muscles all Brach have the same origin, which is attached to the 3 medial epicondyle of the humerus. io- radial is 1. Pronator teres 4 2. Flexor carpi radialis 3. Flexor carpi ulnaris 4. Flexor digitorum superficialis 5. Palmaris longus Fig 2. Showing superficial muscles of the posterior compartment.  Pronator Teres The pronator teres has two heads, the humeral head and the ulnar head. The median nerve enters the Pronat forearm between the two heads. or teres Origin :- Humeral head- Medial epicondyle of the humerus. Ulnar head- Medial border of the coronoid process of the ulna. Radi Insertion :- us Lateral aspect of the shaft of the radius. Nerve supply :- Median nerve, C6 and C7. Action :- Pronation of the forearm. Flexion of the forearm. Fig 3. Pronator teres.  Flexor carpi radialis, palmaris longus, and flexor carpi ulnaris Flexor carpi radialis Origin:- Medial epicondyle of the humerus. Insertion:- Base of the second and third metacarpal bones. Nerve supply:- Median nerve, C6 and C7. Palma Action:- Flexes the hand at the wrist joint. Abducts the hand at the wrist joint. ris Prona longu Palmaris longus tor sFlex Origin:- Medial epicondyle of the humerus. teres or Insertion:- Flexor retinaculum and palmar aponeurosis. Nerve supply:- Median nerve, C7 and C8 Flexor carp Action:- Flexes the hand at wrist joint. carpi i Flexor carpi ulnaris. radiali ulna Origin:- s ris Humeral head- Medial epicondyle of the humerus. Ulnar head- Medial aspect of the olecranon process of the ulna and the posterior border of the ulna. Insertion:- Pisiform bone, hook of the hamate, and base of the fifth metacarpal bone. Nerve supply:- The ulnar nerve, C7, C8, and T1. Action:- Flexes the hand at wrist joint. Fig 4. Flexor carpi radialis and ulnaris and palmaris longus Adducts the hand at wrist joint  Flexor digitorum superficialis. Origin:- Humeroulnar head: Medial epicondyle of the humerus and the medial margin of the coronoid process of the ulna. Radial head: Rising from the oblique line on the anterior surface of the shaft of the radius. Flexor Insertion:- The muscle belly gives rise to four tendons digitoru distally. Each of the tendon attaches to the sides of the middle phalanx of the four medial finger. m superfici Nerve supply:- Median nerve, C8 and T1. alis. Action:- Flexes the middle phalanx of fingers. Flexes the proximal phalanx of fingers (weak). Flexes the wrist. Fig 5. Flexor digitorum superficialis.  Deep Muscles of the anterior compartment. Brachi o- The deep muscles of the forearm comprise radiali of the flexor pollicis longus, flexor s (cut) digitorum profundus and pronator quadratus. 1 21 1. Flexor digitorum profundus. Tendon 2. Flexor pollicis longus. of carpi 3.Pronator Quadratus flexor radialis (cut) Fig 6. Deep muscles of the anterior compartment.  Flexor digitorum profundus and flexor pollicis longus Flexor pollicis longus Origin:- Middle of the anterior surface of the shaft of the radius and from the adjoining part of the interosseous membrane. Insertion:- The tendon passes distally through the carpal tunnel and attaches to the distal phalanx of the thumb. Flexor Nerve supply:- The anterior interosseous branch of the median nerve. Flexor digitoru Action:- Flexes the phalanges of the thumb. pollici m Flexor digitorum profundus s profun Origin:- Upper three-quarters of the anteriomedial shaft Pronato longu dus of the ulna. Insertion:- The muscle divides into four tendons just prior rs to traversing the carpal tunnel. They attach to the quadrat distal phalanx of the four fingers. Nerve supply:- The medial part is supplied by the ulnar us nerve, the lateral portion is supplied by the anterior interosseous branch of the median nerve, C8 and T1. Action:- Flexes the finger. Exclusive flexor of the distal phalanx. Weak flexor of the wrist. Fig 7. Flexor digitorum profundus and flexor pollicis longus.  Pronator Quadratus Flexor pollici Flexor Origin:- Lower quarter of the s digitorum anterior surface of the shaft of longu profundus the ulna. s Pronato r Insertion:- Lower quarter of the quadrat anterior surface of the shaft of Flexo us the radius. r carpi Nerve supply:- The anterior radia Flexor interosseous branch of the lis carpi median nerve. (cut) ulnaris (cut) Action:- Pronates the forearm. Fig 8. Pronator quadratus.  Arteries and Nerves of the anterior compartment. Ulnar artery:- Larger than the radial artery. It passes between the arch formed by the radial and ulnar attachment of the flexor digitorum superficialis and descends through the anterior compartment. It enters the palm of the hand in front of the flexor retinaculum, and promptly divides in superficial and deep palmer branches. Brach Branches- Muscular branches- to the muscles of the anterior ial Medi compartment. artery Recurrent branches- to the anastomosis around the an wrist joint nerv Branches to the anastomosis around the wrist joint Common interosseous artery- arises in the upper part e of the ulnar artery and then divides in the Uln anterior and posterior interosseous arteries. ar Anterior interosseous artery:- arises from the Radi nerv common interosseous artery and descends in al e the anterior compartment to eventually join the anastomosis around the wrist joint. It nerv Uln supplies the deep flexor muscles, and gives off nutrient branches to the the radius and e ar ulna. arte ry Fig 9. Arteries and nerves of the anterior compartment.  Arteries and Nerves of the anterior compartment. Radi Brach Posterior interosseous artery- arises from the common interosseous artery and and enters the al ial posterior compartment. nerv artery Medi e Superfi Radial artery:- It begins in the cubital fossa when the an brachial artery divides into the radial and ulna artery. cial Uln nerv It passes distally, travels under the brachioradialis, resting on the deep flexor muscles. The artery briefly radial ar e travels on the lateral side of the radius, before nerve Uln nerv travelling over the anterior surface of the radius. The artery then winds around the lateral aspect of the Radi ar e wrist, before entering the palm of the hand to form Medi arte the deep palmer arch. al arter ryan Branches- Muscular branches: to the neighbouring muscles. nerv y Branches to the anastomosis around the wrist and elbow e joint. Superficial palmer joint: arises just above the wrist, frequently joins the ulnar artery to give rise to the superficial palmer arch. Fig 10. Arteries and nerves of the anterior compartment.  Nerves of the anterior compartment Median Nerve The median nerve leaves the cubital fossa in between the two heads of the pronator teres. It descends between the superficial and deep flexor muscles. At the wrist it lies superficially, before entering the palm behind the flexor retinaculum. Branches:- Muscular branch:- all the superficial muscles of the anterior compartment except flexor carpi ulnaris. Articular branches: to the elbow joint Anterior interosseous nerve: arises from the median nerve as it emerges from the two heads of the pronator teres. (see below) Palmer cutaneous Branch: Distributed to the skin over the lateral part of the palm. Anterior interosseous nerve It arises from the median nerve (see above) and then descends down the anterior surface of the interosseous membrane. Branches- Muscular branches: all the muscles of deep flexion in the anterior compartment except the medial part of digitorum profundus.  Superficial muscles of the posterior compartment. The superficial muscles of the posterior compartment are mainly concerned with the extension at wrist joint and of the digit. The muscles in this group comprise of the Extensor carpi radialis brevis, extensor digitorum, extensor digiti minimi, extensor carpi ulnaris, Ancone and the two more lateral lying brachioradialis and extensor carpi radialis longus. us 3 2 NB- The anconeus also lies in the posterior compartment but is functionally 1 very different to the rest of the muscles in this group. Its action are to aid the triceps in extension at the elbow joint. 2 1. Extensor carpi radialis longus 2. Extensor digitorum 3. Extensor carpi ulnaris 4. Extensor digiti minimi 5.Brachioradialis 4 6.Extensor carpi radialis brevis. Fig 11. Superficial muscles of the posterior compartment.  Extensor carpi radialis longus and brevis, and extensor carpi ulnaris Extensor carpi radialis longus Origin:- From the lower third of the lateral supracondylar ridge of the humerus. Insertion:- Posterior surface of the base of the second metacarpal bone. Nerve supply:- Radial nerve, C6 and C7. Extensor Action:- Extends and abducts the hand at the wrist joint. carpi Extensor carpi radialis brevis Extensor radialis Origin:- From the common tendon attached to the lateral epicondyle carpi longus of the humerus. Extenso radialis Insertion:- Posterior surface of the base of the third metacarpal bone. r carpi brevis Nerve supply:- Posterior interosseous nerve, C7 and C8. ulnaris Action:- Extends and abducts the hand at the wrist joint. Extensor carpi ulnaris Origin:- From the common tendon attached to the lateral epicondyle of the humerus. Insertion:- Posterior surface of the base of the fifth metacarpal bone. Nerve supply:- Posterior interosseous nerve, C7 and C8 Action:- Extends and adducts the hand at wrist joint. Fig 12. Extensor carpi radialis brevis and longus and extensor carpi ulnaris.  Extensor digitorum and extensor digiti minimi Extensor digitorum Origin:- From the common tendon attached to the lateral epicondyle of the humerus. Insertion:- The muscle divides into four tendons which pass to the fingers and form the dorsal expansion. On the dorsum of the hand these are interconnected by fibrous tissue. Near the proximal interphalangeal joint of each finger the expansions divide into the central part, which inserts into base of the middle phalanx, and the two lateral parts, which insert into the base of the distal phalanx. Extens Nerve supply:- Posterior interosseous nerve, C7 and C8 Action:- Mainly it extends the metacarpophalangeal joint, but or it also assists in extending the proximal and distal digitor interphalangeal joint and the arm. Extenso um Extensor digiti minimi r digiti Origin:- From the common tendon attached to the lateral minimi epicondyle of the humerus. Insertion:- Via two tendons to the dorsal expansion for the little finger. Nerve supply:- Posterior interosseous nerve, C7 and C8 Action:- Assists in the extension of the little finger. Fig 13. Extensor digitorum and extensor digiti minimi.  Brachioradialis Flexor Origin:- From the upper twp thirds of carpi the lateral supracondylar ridge of radialis the humerus. Brachio -adialis Insertion:- Base of the styloid process of the radius. Extensor carpi radialis longus Nerve supply:- Radial nerve, C5 and C6. Extensor carpi radialis brevis Action:- It flexes the forearm (despite being being served by an ‘extensor’ nerve), assists in rotating or restoring the arm into midprone position, depending on the initial position. Deep muscles in the posterior compartment. 1 2 1. Supinator. 2. Abductor pollicis longus. 3 4 3. Extensor pollicis longus. 5 4. Extensor indicis. 5. Extensor pollicis brevis. Extensor pollicis longus and brevis, and abductor pollicis longus Abductor pollicis longus Origin:- Middle of the posterior surface of the shaft of the ulna and radius. Insertion:- Posterior surface of the base of the first metacarpal bone. Nerve supply:- The posterior interosseous nerve, C7 and C8. Action:- Abducts and extends the thumb. Extensor pollicis longus Origin:- From the posterior surface of the ulna. Insertion:- Posterior surface of the base of the distal phalanx of the thumb. Abductor Nerve supply:- The posterior interosseous nerve, C7 and C8. pollicis Action:- Extends the thumb. longus. Extensor Extensor pollicis brevis pollicis Origin:- Posterior surface of the radius. Insertion:- Posterior surface of the proximal phalanx of the thumb longus Nerve supply:- The posterior interosseous nerve, C7 and C8. Extensor Action:- Extends the thumb. pollicis brevis Ana