Anatomy Lecture 2 for SPBU-GM Students PDF

By the end of this lecture, you should be able to: Types of bones Structure of long bone 1. Classify bones according to shape, structure and General features of bones development 2. De...

By the end of this lecture, you should be able to: Types of bones Structure of long bone 1. Classify bones according to shape, structure and General features of bones development 2. Describe structure of long bone , growth and blood supply. Dr. Shereen Adel Professor of Anatomy & Embryology Types of bones according to structure: Bone: Compact bone: ▪ Hard, calcified , highly vascular connective hard ,dense like ivory tissue. forming surface of bones. ▪ It consists of bone cells, intercellular matrix made of collagen fibers, Cancellous bone: inorganic salts and it consists of Trabeculea minerals with spaces like a sponge. It is present inside bone.  Types of bone according to development: Cartilaginous Ossification : Bones ossify from specialized Starts from a cartilage model like long bones, mesenchymal cells by either : vertebral column. Starts in intra uterine life Membranous Ossification: 8th week by appearance of bone develop directly from primary centre of ossification membrane of connective tissue in middle of shaft the part - skull bones for protection of ossified is called diaphysis. underlying brain, - shaft of clavicle - facial bones After birth secondary center of ossifications appear in ends of long bones this part is called epiphysis leaving a plate of cartilage for elongation of bones. Complete fusion occurs at puberty in girls earlier than boys Types of bone according to shape: Types of bone according to shape: Flat bones : shallow Long bones : formed of shaft Two plates of compact with (diaphysis) and 2 ends ( epiphysis) spongy bone and bone marrow like bones of arm and thigh in between as scapula , sternum and bones of vault of skull for protection. Short bones: cuboidal as carpal Irregular bones: irregular in and tarsal bones made of spongy shape, as vertebrae and hip bone surrounded by compact bone bone Types of bone according to shape: Types of bones : Pneumatic bones: Bones containing air filled spaces and lined by mucus 1- Long bones membrane as maxilla Humerus - femur Lighten weight, Resonance of voice Air conditioning. 2- Short bones Carpal - tarsal bones Sesamoid bones: Bony nodules embedded in tendons as patella in tendon of quadriceps. 3- Flat bones Scapula Protect tendon from excessive wear 4- Irregular bones Vertebra 5- Sesamoid bones Patella 6- Pneumatic bones Maxilla  Parts or structure of long bone A long bone has two parts: the diaphysis and the epiphysis. The diaphysis is the tubular shaft that runs between the proximal and distal ends of the bone. The hollow region in the diaphysis is called the medullary cavity, which is filled with yellow marrow. The walls of the diaphysis are composed of dense and hard compact bone. When the bone stops The epiphysis is filled with growing in early adulthood spongy bone. Each epiphysis (approximately 18–21 years), the cartilage is meets the diaphysis at the replaced by osseous tissue metaphysis, the narrow area and the epiphyseal plate that contains the epiphyseal becomes an epiphyseal line. plate (growth plate), a layer of hyaline (transparent) cartilage in a growing bone. the epiphyses are covered with articular cartilage. the bone is covered with a fibrous membrane called the periosteum. Arterial supply of bone: Periosteum It consists of fibrous vascular A typical long bone has layer and inner cellular three main sources: covering surface of bones. the nutrient artery, Absent in articular surface & the metaphyseal and sesamoid bones epiphyseal arteries, and the periosteal arteries. Functions: The nutrient artery is 1. Give attachment to muscles, tendons & ligaments the main blood vessel 2. Source of blood supply that enters the 3. Growth of bone in width 4. Healing of fractured bones diaphysis via the nutrient foramen. External Features of Bone : External Features of Bone : 1- Elevations : 1- Elevations : Crest - projecting line - Line - crest Line: linear elevation - Tubercle – tuberosity - trochanter - Process - spine External Features of Bone : External Features of Bone : 1- Elevations : 1- Elevations : Trochanter - A large rough (elevation) prominence. Spinous Process - A raised, sharp elevation of bone Tuberosity - A medium rough (elevation) (pointed) prominence. Process; - A raised, elevation of bone (not pointed) Tubercle - Asmall rough (elevation) prminence. External Features of Bone : 2 - Depressions : 1- Depressions : Fossa - A shallow depression in the bone surface. Fossa Groove - elongated depression in the bone surface Notch - A depression in a bone border Groove or sulcus Notch  External Features of Bone : 3 - Perforations : 3- Perforations: - Foramen – canal - fissure Fissure - An open slit (de roofed canal) 4 – Articular Surfaces : Foramen - A hole - Head – condyle – trochlea - facet External Features of Bone : 4- Articular surfaces: Head - A rounded, prominent bone that forms part of a joint. Neck - The segment between the head and the shaft of a bone. Condyle - Refers to a large articular prominence Epicondyle - A prominence that sits atop of a condyle (non articular). Facet - A smooth, flat surface that forms a joint  Assignment Describe structure of long bone & its blood supply. Introduction to Craniology Norma Frontalis Frontal bone Nasal bone Mandible  Supraorbital foramen (or notch) Infraorbital foramen mental foramen Norma Verticalis Frontal bone Bregma Parietal Parietal bone bone Sagittal suture Lambda Occipital bone  Anterior Fontanelle Posterior Fontanelle Norma Occipitalis Sagittal suture Parietal Parietal bone bone Lambda Lambdoid suture Occipital bone External occipital Crest External occipital protuberance Norma Lateralis Frontal Parietal bone bone Temporal Bone Zygomatic bone  Sup. Temporal line Inf. Temporal line Pterion Asterion Pterion: Is an H-shaped suture where 4 bones meet; the frontal, parietal, temporal and greater wing of sphenoid. It is the ossified anterolateral fontanelle at the age of 3 months. The center of the pterion lies 4 cm above the mid-point of the zygomatic arch and 3.5 cm behind the frontozygomatic suture. It is related to the anterior division of middle meningeal a. Pterion: Since it is very thin, the pterion is the most frequentally fractured part of skull in car accidents leading to hemorrhage (extradural hematoma) which compresses the motor area of the brain. Asterion: Is the meeting point of the parietal, occipital and mastoid part of temporal bones. It is the ossified posterolateral fontanelle at the end of the 1st year.  Anterolateral Posterolateral Fontanelle Fontanelle Fontanelles: Fontanelles are membranous areas in skull that allow overlap during birth. Anterior fontanelle at the bregma is rhomboid in shape and it ossifies (changes to bone) and closes at 1½ years. Posterior fontanelle is present at the lambda, triangular in shape, ossifies and closes at 6 months. Anterolateral closes at 3 months and posterolateral fontanelles closes at the end of the 1st year. Norma basalis interna (Cranial Cavity)  Anterior cranial fossa Middle cranial fossa Posterior cranial fossa Anterior Cranial Fossa Frontal Bone Ethmoid Bone Sphenoid Bone  Anterior Cranial Fossa ▪ Frontal crest ▪ Orbital plate of frontal bone ▪ Lesser wing of ▪ Crista galli sphenoid ▪ Cribriform plate of ethmoid Anterior Cranial Fossa ▪ Frontal crest ▪ Orbital plate of frontal ▪ Foramen caecum bone ▪ Crista galli ▪ Lesser wing of sphenoid ▪ Cribriform plate of ethmoid Middle Cranial Fossa  Sphenoid Bone Temporal bone Body Squamous part Greater wing Petrous part Parietal bone Posterior Cranial Fossa Sphenoid Bone Temporal Bone Petrous part Parietal Bone Occipital Bone  Norma Basalis Externa Divisions Anterior Part Middle Part Posterior Part Anterior Part Alveolar margin Palatine Process of Maxilla Horizontal plate of Palatine  Middle Part Vomer of nose Sphenoid Bone Medial Pterygoid plate Pterygoid Processes Greater wing Lateral Pterygoid plate Petrous part of Temporal Bone Posterior Part Occipital Bone Basilar part Mastoid process of Condylar part Temporal bone Squamous part The mandible Symphysis menti  The mandible Ramus Alveolar part Body Base Body of the mandible Inner It has two surfaces surface It has two borders Outer surface Body of the mandible Lateral aspect (Outer surface) Oblique line Mental Protuberance Mental foramen Mental Mental Angle of the symphysis Tubercles mandible  Body of the mandible Medial aspect (Internal surface) Mandibular foramen Lingula Mylohoid groove Mylohoid line Genial Sublingual tubercle Digasteric Submandibular fossa fossa fossa Ramus of the mandible Condylar head Pterygoid fovea Coronoid process Neck Mandibular notch  Introduction to myology Back muscles Dr. Shereen Adel Professor of Anatomy & Embryology By the end of this lecture, you should be able to: By the end of this lecture the student will be able to identify: 1. Types function and distribution of fascia 2. Different types of muscles 3. Back muscles The FASCIA Skin It is the tissue which lies Superficial immediately fascia under the skin. Deep fascia It is divided into: (a) Superficial fascia (b) Deep fascia  The superficial fascia is firmly attached to the skin in : 1 ) scalp. 2 ) back of the neck. 3 ) plams of the hands. 4 ) soles of the feet. The superficial fascia is loosely attached to the skin on; 1 ) dorsum of the hands 2 ) dorsum of the feet. The superficial fascia is devoid of (does not have) adipose (fatty) tissue in the: 1) eyelids. 2) auricle of the ear. 3) penis and scrotum. 4) clitoris. It is rich in fat in 1- Breast 2- Buttocks Functions of Superficial Fascia ❑ Facilitate movements of skin ❑ Bad conductor of heat keeps body temperature constant ❑ Gives body its shape ❑ Contains blood vessels , nerves & sometimes muscles( face& scrotum) ❑ Holds skin firmly to deeper structures by bundles of collagen DEEP FASCIA Dense fibrous membranous layer of connective tissue that invests muscles. ❑ It is well developed in limbs ❑ Thin in thorax & abdomen ❑ Absent in most of the face & anterior abdominal wall DEEP FASCIA In limbs deep fascia sends intermuscular septa which M attach to the B M bones & so divide the muscles into B M different functional & regional groups DEEP FASCIA It is thickened around distal joints to form retinacula. Retinacula help to fix muscle tendons in position DEEP FASCIA It is thickened in palms of hands to form palmar aponeurosis. DEEP FASCIA It is thickened in soles of feet to form plantar aponeurosis. DEEP FASCIA Flexor tendons are fixed in the fingers & toes by thickening of deep fascia called fibrous flexor sheaths. Functions of Deep Fascia ❑ Covers the muscles & assist in their action by pressure ❑ Gives rise to septa which divide limbs into compartments ❑ It is thickened in palm & sole forming palmer & planter aponeurosis for protection ❑ It is thickened around joints forming retinacula to hold tendons in place ❑ It is thickened opposite the flexor tendons of fingers forming fibrous flexor sheaths to stabilize tendons ❑ Helps in venous return by squeezing blood towards the heart and limiting distention in compartments Skeletal Muscles: ❑ Striated alternating light and dark bands & voluntary ❑ Main bulk of body ❑ Muscles of limbs ❑ Rapid contractions Classification according to shape & line of pull A-Parallel : Wide range of movement & less force 1- Quadrilateral: Quadratus lumborum 2-Fusiform Biceps 3-Strap Sartorius 4- Strap with tendinous intersections Rectus abdominus B-Oblique: Range of movement is less& Force is more Either Pennate or Triangular 1) Pennate: Unipennate: ❑ Fibers along one side of tendon: Flexor pollicis longus Bipennate: ❑ Fibers on both sides of tendon ❖ Dorsal interossei ❖ Rectus femoris Circumpennate: Multipennate: ❑ Fibers converge ❑ Series of bipennate from all directions ❖ Deltoid on a tendon that lies in center ❖ Tibialis anterior 2)Triangular : ❑ Fibers converge from wide attachment to narrow tendon ❖ Temporalis D Circular : ❑ Forms complete circle ❖ Orbicularis oculi E- Spiralized: ❑ Upon contraction approximate their attachments bring them to same plane and may be twisted: ❖ Trapezius Attachments of muscles 1-Fleshy fibers :popliteus 2-Tendon: tendo calcaneus 3- Aponeurosis: flat fibrous sheet External oblique muscle 4-Raphe: fibrous band , it separates 2 fleshy muscles from each other one on each side Mylohyoid raphe Action of Muscles ❑ Prime mover: initiate movement(agonist) ❑ Antagonist: antagonize movement opposite action of agonist ❑ Synergist: prevent unwanted movements when prime movers can move 2 joints and movement is unwanted in one of this joints the movement at the unwanted joint is prevented by synergists ❑ Fixator: stabilize the origin of prime mover to act efficiently The muscles of the back * They attach upper limb to vertebral column 1 2 The first layer: 3 1 1. Trapezius. 2. Latissimus dorsi. The second layer: 1. Levator scapulae. 2. Rhomboidus minor. 3. Rhomboidus 2 major. FIRST LAYER SECOND LAYER  The muscles of the back 1 2 3 1 Check yourself? 2 Assignment Describe types of oblique muscles  Anatomical Terminology skeleton Dr. Shereen Adel Professor of Anatomy & Embryology From the study of anatomy By the end of this lecture, you should be able to: real medicine begins! Anatomy: 1- Describe anatomical position. it is the study of morphological structure of the body 2- Identify different anatomical planes. 3- Describe parts of axial and appendicular skeleton. Normal anatomy is a basic (fundamental) discipline that allows 4- Identify terms of position & movement. further qualitative study of theoretical medical disciplines (histology, physiology, etc.) and clinical disciplines (surgery, therapy, traumatology). Fields of anatomy Fields of anatomy I- Macroscopical Anatomy (Gross morphology): study of the IV- Applied and clinical Anatomy: study of the macroscopic body structure by the naked eye. structure of the body that is related to the practice of medicine. II- Microscopical Anatomy: study of the body structure using the V- Surface Anatomy: locate the body structures in relation to the microscope. body surface. III- Developmental anatomy (Embryology): study of the VI- Radiological Anatomy: interpretation of normal body sequence of events to produce a full-term baby. structures in a radiologic images  Anatomical planes Anatomical position ❑ Body is standing erect ❑ Face is looking forward Median plane: ❑ Upper limb is hanging by side Vertical plane passing through ❑ Hands are facing forwards center of body dividing it into 2 ❑ Lower limbs are parallel equal halves Supine position : lying horizontal Paramedian plane: with face and body facing up Vertical plane dividing body into 2 Prone position :lying horizontal unequal halves with face looking down Coronal plane: Vertical plane perpendicular on median plane dividing body into anterior& posterior Transverse: Horizontal plane dividing body to upper and lower parts Identify the type of the section Anatomical terms of position Terms of position ▪Anterior: ❖Median: Structure is nearer to front Structure lies in median plane ▪Posterior: ❖Medial : Structure lies nearer to median plane Structure is nearer to back ❖Lateral: ▪Superficial : Structure lies away from median plane Structure nearer to surface ❖Superior: ▪Deep: Structure close to upper end of the body Structure away from surface ❖Inferior: ▪Internal : Structure close to lower end of body Structure is inside organ or cavity ▪External: Structure is towards outer aspect of organ  Terms of position Skeleton: Proximal Structure is nearer to It is divided into axial trunk & appendicular Distal : Axial skeletal : Structure is away from trunk includes skull ,sternum, hyoid bone, ribs(12) & vertebral Ipsilateral: column Structure is on same side Contralateral: Appendicular Structure on opposite side skeletal: includes bones of upper limb & lower limbs The true ribs are the ribs Skeleton: that directly articulate with the sternum with their It is divided into axial costalcartilages; they are the & appendicular first seven ribs Axial skeletal : The false ribs are the ribs includes skull that indirectly articulate with ,sternum, hyoid bone, the sternum, as their costal ribs(12) & vertebral cartilages connect with the column seventh costal cartilage; by Appendicular the costochondral joint; They skeletal: includes are the eighth, ninth, and bones of upper limb & tenth rib lower limbs The 11th and 12th pairs (floating ribs) are shorter than the others and do not reach to the front of the body Vertebral Column Curves of Vertebral Column Includes vertebrae and Primary: vertebral column is concave intervertebral anterior at birth Secondary: disc : 1. Cervical curve: cervical curve 7 cervical vertebrae becomes convex anterior when 12 thoracic child extends his neck at 3-4 5 lumbar months 5 sacral fused together 2. Lumbar curve: lumbar curve forming sacrum becomes convex anterior when child begins to walk due to 4 coccygeal fused forming strengthening of muscles of the coccyx back at 12 -18 months  Appendicular Skeleton of Appendicular Skeleton of lower limbs Upper limbs Pelvic girdle: Hip bone connect lower limb Shoulder girdle: scapula& clavicle To axial skeleton at sacroiliac joint connect upper limb to trunk at Thigh : Femur sternclavicular joint Leg: Tibia & Fibula Foot Arm: Humerus -Tarsal bones(7) -Metatarsals (5) numbered from Forearm: medial to lateral Radius &Ulna -Phalanges 3 in each toe except big toe 2 Hand: Carpal (8) , metacarpals (5) numbered from One to five from lateral to medial & phalanges 3 in each finger 2 in thumb TEREMS OF MOVEMENT Functions of skeleton Flexion refers to a movement that decreases the angle between two Supports the body body parts.= BEND THE JOINT Act as a lever upon. which muscle acts Extension refers to a Protects vital movement that increases structures the angle between two Transmits body body parts.= STRETCH THE JOINT weight Red bone marrow inside bones produces red blood cells Mineral reservoir Abduction : Moving a limb away from the ❑ Dorsiflexion midline Bending the foot at the ankle Adduction: upwards Moving a limb towards ❑ Plantar flexion the midline Bending the foot at the ankle downwards Adduction :of fingers Approximating them together Abduction: of fingers Spreading them apart  Medial rotation is a Elevation rotational movement Moving a part upward towards the midline. ( elevation of shoulder or It is sometimes mandible) referred to as internal Depression rotation. Moving a part downward Lateral rotation is a ( depression of shoulder or rotating movement mandible ) away from the midline.. 1-Supination Lateral rotation of forearm which Inversion involves the brings the palm of hand to face movement of the forwards sole towards the median plane – so that the sole faces in a medial direction. Eversion involves the movement of the sole 2-Pronation away from the median Medial rotation of the forearm plane – so that the sole which brings the palm of hand to faces in a lateral face backward direction. Protraction Moving a part forward ( protraction of mandible or shoulder) Describe the movements of these joints? Retraction Moving a part backward ( retraction of mandible or shoulder)  Opposition of thumb : Circumduction: thumb touches tip of other fingers Combination of flexion, extension adduction And abduction find the order of movements? Describe the movements of baby crawling Which of the following correctly describes abduction of a joint? A. Decreases the joint angle B. Increases the joint angle C. Movement away from the midline D. Movement towards the midline Which of the following refers to a Assignment movement in a superior direction? A. Flexion B. Adduction Describe anatomical position. C. Plantar flexion D. Elevation  Topography of upper limb (Pectoral girdle-Shoulder- Arm- Forearm-Hand) Dr. Shereen Adel Professor of Anatomy & Embryology By the end of this lecture, you should be able to: By the end of this lecture the student will be able to identify: 1. Identify muscles, nerves & vessels in pectoral region & shoulder. 2. Identify muscles, nerves & vessels of arm, forearm & hand.  Pectoral Region Muscles of pectoral region: 3 Connects U.L.to thoracic wall 4 2 1 Deep to pectoralis major are: 2. Pectoralis Minor 3. Subclavius muscle 1. Pectoralis Major muscle 4. Clavipectoral fascia (between 2 & 3) Breast: Modified skin gland in superficial fascia, formed of mammary gland + fat + 4 covering skin. Serratus Anterior Muscle: A muscle arising from the upper 8 ribs & inserted into scapula 5 Axilla (Arm Pit) 4 sided pyramidal space between upper part of thoracic wall & medial side of arm 6 Shoulder (Scapular) Region Consists of a group of muscles (6) connecting the scapula with the humerus: 1. Deltoid 2. Supraspinatus 3. Infraspinatus 4. Teres minor 5. Teres Major 6. Subscapularis (seen from front of scapula) 7 8 Arm The arm is divided by 2 intermuscular septa extending from deep fascia into 2 compartments. The septa are: 1. Medial intermuscular septum 2. Lateral intermuscular septum The compartments are: 1. Anterior compartment 2. Posterior compartment 9  Arm (Ant. Comp.) Muscles: 1. Biceps Brachii muscle: has short head & long head (lateral & passing through the shoulder joint) 2. Coracobrachialis (small muscle lying medial to short head of biceps) 3. Brachialis (deep to biceps) Vessels 1. Brachial artery 2. Basilic & cephalic veins 10 Arm (Ant. Comp.) Nerves: 1. Musculocutaneous nerve: 1 supplies muscles of front of arm (biceps, coracobrachialis & brachialis). Pierces coracobrachialis. 2. Median nerve: Gives no branches in 2 the arm 3. Ulnar nerve: Gives no branches in the arm. 3 * Medial in position * In the middle of arm, pierces medial intermuscular septum to posterior comp., passes behind medial epicondyle 11 Arm (Post. Comp.) Muscles: Triceps Brachii muscle: has long head, lateral head Radial nerve & medial head (deep) Long head Vessels: Profunda brachii artery running in spiral groove Nerves: Medial head Radial nerve: 12  Cubital Fossa Definition: triangular intermuscular hollow in front of the elbow. Base of the triangle Lateral Cephalic v. Basilic v. Medial Median cubital v. 13 The main artery used in One of the main veins used in measurement of blood intravenous injections is the pressure is the brachial artery median cubital vein In the cubital fossa 14 15  Front of Forearm Muscles Flexor digitorum superficialis 1st layer Flexor digitorum superficialis Deep layer 16 Nerves & Vessels; Muscles of the front of arm are supplied by median nerve (mainly) + ulnar nerve. Median nerve Brachial artery divides at the level of the neck of Brachial artery the radius into radial & ulnar arteries Radial nerve & vessels (laterally) Ulnar nerve & vessels (medially) 17 Which artery do we commonly use to count the pulse rate? 18 Short muscles of hand (20): 1. Thenar muscles (4) 2. Hypothenar muscles (3) + Palmaris brevis (small muscle in superficial fascia superficial to hypothenar muscles =(4) 3. Lumbricals (4) 4. Palmar interossei (4, sometimes 3) 5. Dorsal interossei (4) 4 Lumbricals 4 Palmar Interossei 4 Dorsal Interossei 19 Short muscles of the hand are supplied by ulnar nerve (mainly) + median nerve Median nerve Median nerve is called “ The Laborer's nerve while the Ulnar nerve is called “The Musician’s nerve”……. WHY? Ulnar nerve & vessels 20 21  Back of Forearm 1 2 Superficial group of muscles (7): Lateral group: 7 2 3 1. Brachioradialis 2. Extensor carpi radialis longus 3 6 54 3. Extensor carpi radialis brevis 4 6 Posterior group: 5 4. Extensor digitorum 5. Extensor digiti minimi 6. Extensor carpi ulnaris 7. Anconeus 22 Deep group of muscles (5): 1. Abductor pollicis longus 5 2. Extensor pollicis brevis 1 3. Extensor pollicis longus 3 4. Extensor indicis 1 5. Supinator 4 2 3 4 2 23 Nerve: Posterior interosseous nerve from radial Artery: Posterior interosseous artery Extensor retinaculum 24  Dorsum of hand 1. Dorsal venous arch: 2. Extensor tendons * In superficial fascia 3. Dorsal Interossei Medial end: Basilic vein Lateral end: Cephalic vein 4. Anatomical Snuff Box Def.: Depression on the lateral part of the wrist 27  28 Assignment List muscles of pectoral region List muscles, vessels & nerves of front of forearm Thank you 30  Introduction to Joints Articulations of head & trunk Dr. Shereen Adel Professor of Anatomy & Embryology INTENDED LEARNING OBJECTIVES (ILO) 1. Define joints 2. Types of joints 3. Describe the articulations of the Head: TMJ, atlanto- occipital joint and atlanto-axial joint. 4. Describe the Joints (Articulations) of the Vertebral Column JOINTS * What is a Joint? It is the site where 2 or more bones meet or it is the site of meeting of a bone & a cartilage. * Classification: * Joints are classified according to their structure and mobility. * There are 3 types of joints: 1. Fibrous joints. 2. Cartilaginous joints. 3. Synovial joints. Dr Ashraf Ramzy  A. Fibrous Joints * The bones are united together by fibrous Sutures of skull tissue. * Have little degree of Syndesmosis Gomphosis movement. (Inferior tibio-fibular Joint) * Have 3 types: 1. Sutures of skull 2. Syndesmosis 3. Gomphosis Dr Ashraf Ramzy 1. Sutures of skull 2. Syndesmosis 3. Gomphosis * Example: Sagittal suture of Inferior tibio-fibular Teeth (Peg & socket). skull. joint. * Ossification: Ossifies with age. Do not ossify. Do not ossify. * Nature: Articular surfaces are Bones are The joint is between connected together connected together the root of the tooth & by strong fibrous by an interosseous the jaw (mandible or tissue. ligament. maxilla). * Movement: Allows slight No movement. No movement. movement during If movement occurs & delivery. the tooth becomes loose → pathological case. Dr Ashraf Ramzy B. Cartilaginous Joints * The bones are united together by cartilage. * Have 2 types: 1. Primary Cartilaginous joint. 2. Secondary Cartilaginous joint. Dr Ashraf Ramzy  1. Primary Cartilaginous joint 2. Secondary Cartilaginous (Synchondrosis) joint (Symphyses) * Nature: The articular surfaces are The articular surfaces are connected together by hyaline connected together by hyaline cartilage. & fibrocartilage. * Ossification: Ossifies with age (i.e. temporary Do not ossify with age (i.e. joint). permanent joint). * Movement: No movement (immobile). Allows slight movement. * Examples: 1. Epiphyseal plate of long bones. Midline joints: 2. Joints between ribs & costal 1. Intervertebral discs. cartilages. 2. Symphysis menti. 3. Joint between 3. Symphysis pubis. sternum & 1st costal 4. Joints between cartilage. parts of sternum. C. Synovial Joints * They are freely movable joints. * They are the most common & important types. * They have a cavity containing synovial fluid. * Structure of synovial joints: 1. Articular surfaces of bones are covered by a thin layer of hyaline cartilage (articular cartilage). 2. The joint is surrounded by a fibrous (articular) capsule. 3. The joint has a joint cavity. Dr Ashraf Ramzy C. Synovial Joints 4. The joint cavity is lined by a synovial membrane which lines the fibrous capsule and covers the non-articular parts of bones inside the joint. The synovial membrane secretes the synovial fluid. 5. Each joint is provided by a number of ligaments in order to increase its stability. These ligaments may be: a. Capsular ligaments → localized thickenings of the capsule. b. Extracapsular ligaments → outside the capsule: such as medial and lateral ligaments of knee joint. c. Intracapsular ligaments → inside the capsule: such as cruciate ligaments of knee joint. Dr Ashraf Ramzy  C. Synovial Joints 6. Some synovial joints may contain intracapsular structures such as: a. Fibrocartilaginous structures as: * Articular disc as in sternoclavicular joint & temporo-mandibular joint. * Menisci as in knee joint * Labrum as in shoulder & hip joints. b. Tendon of a muscle as long head of biceps tendon inside shoulder joint. Dr Ashraf Ramzy Menisci in Knee joint Long head of biceps inside Labrum of shoulder joint shoulder joint Dr Ashraf Ramzy Types of synovial joints * They are classified according to the axes around which the movements occur & shape of articular surface into: 1. Uniaxial joints → movement around one axis. 2. Biaxial joints → movements around 2 axes. 3. Multiaxial (polyaxial) joints → movements around more than 2 axes. Dr Ashraf Ramzy  I. Uniaxial Joints (Movement around one axis) Hinge joint Pivot joint Bicondylar joint (modified hinge) * Axis of Movement around a Movement around a Movement around a movement: horizontal axis. vertical (or horizontal axis + longitudinal) axis. slight rotation. * Movements: Flexion & extension. Rotation. Flexion & extension + slight rotation. * Examples: 1. Elbow joint. 1. Superior & inferior 1. Knee joint. 2. Interphalangeal radio-ulnar joints. joints. 2. Median atlanto- axial joint. 3. Ankle joint. Dr Ashraf Ramzy Dr Ashraf Ramzy II. Biaxial Joints (Movement around two axes) Ellipsoid (condyloid) Saddle joint joint * Shape of articular A condyle articulates with Concavo-convex surfaces surfaces: an elliptical depression. articulate together. * Movements: * Flexion & extension. * Flexion & extension. * Abduction & adduction. * Abduction & adduction. + Rotation (or opposition or circumduction). * Examples: 1. Wrist joint. Carpo-metacarpal joint of 2. Metacarpo-phalangeal js. thumb. Dr Ashraf Ramzy  Metacarpo-phalangeal joints Carpo-metacarpal joint of thumb Wrist joint Dr Ashraf Ramzy III. Multiaxial (Polyaxial) Joints (Movement around more than two axes) Ball & Socket joint Plane joint * Shape of A convex sphere articulates with Gliding flat surface. articular a concave depression. surfaces: * Movements: All types of movements: * Least moveable joints. * Flexion & extension. * Slight movements in all directions. * Abduction & adduction. * Medial & lateral rotation * Non-axial joint. * Circumduction * Examples: Shoulder & hip joints. Acromio-clavicular joint. Dr Ashraf Ramzy Factors affecting stability of joints 1. Shape of articular surface. 2. Strength of the ligaments & the capsule of the joint. 3. The strength & tone of surrounding muscles. Dr Ashraf Ramzy  Articulations of the Head 1) Sutures of the Skull  They are fibrous joints that connect the bones of the skull, allowing no movement (fixed immobile joints) 2) Temporo-mandibular Joint Articular tubercle of temporal bone Type; bi-axial condylar Mandibular fossa of temporal bone synovial joint (some texts classify it as an ellipsoid synovial joint) White fibrocartilage covering mandibular fossa Head (condylar process) of mandible White fibrocartilage covering head of mandible Articular surfaces; Below; head (condylar process) of mandible Articular tubercle of temporal bone Above; mandibular fossa (glenoid fossa) Mandibular fossa of temporal bone and articular tubercle of temporal bone (N.B.) Articular surfaces are covered by white fibrocartilage. White fibrocartilage covering mandibular fossa Head (condylar process) of mandible White fibrocartilage covering [N.B.] It is unique in that it is a bilateral joint that head of mandible functions as one unit. Fibrous capsule; Capsule is attached above to margins of mandibular fossa and articular eminence Above; attached to margins of the mandibular fossa and Capsule is thickened laterally to form articular eminence temporomandibular ligament Below; attached around neck Capsule is attached below to of mandible neck of mandible All around; attached to Mandibular fossa of margins of the articular disc temporal bone Articular eminence of temporal bone (N.B.) Capsule is thickened laterally to form the Fibrous capsule temporomandibular of TMJ ligament Articular disc of TMJ Lateral pterygoid muscle Articular disc; Capsule is attached above to margins of mandibular fossa and articular eminence  An oval plate of Capsule is thickened fibrocartilage that divides laterally to form temporomandibular joint cavity into upper and ligament lower compartments  Its upper surface is Capsule is attached below to neck of mandible concavo-convex, while its lower surface is concave. Mandibular fossa of temporal bone  Its periphery is attached to Articular eminence of temporal bone the fibrous capsule all- around. Fibrous capsule  It receives the insertion of of TMJ the lateral pterygoid muscle. Articular disc of TMJ Lateral pterygoid muscle  Sphenomandibular ligament Temporo- Ligaments of TMJ; mandibular ligament 1) Temporo-mandibular ligament;  Triangular ligament, on lateral aspect of the joint (formed by the thickened lateral part of the capsule). Stylomandibular  Attached above to the root of zygomatic arch ligament  Attached below to lateral aspect of neck of mandible Sphenomandibular ligament  It is the only proper ligament that supports the joint. 2) Stylo-mandibular ligament;  Cord-like ligament, on posterior aspect of the joint Styloid process  Attached above to anterior aspect of styloid process near its tip Stylomandibular  Attached below to angle and posterior border ligament of ramus of mandible Angle of mandible Sphenomandibular ligament Temporo- Ligaments of TMJ; mandibular ligament 3) Spheno-mandibular ligament;  Cord-like ligament, on medial Stylomandibular aspect of the joint ligament  Attached above to spine of sphenoid bone Sphenomandibular ligament  Attached below to lingula of mandible  It is pierced by the inferior alveolar nerve and vessels Styloid process Stylomandibular ligament Angle of mandible Forward gliding movement of the Lateral pterygoid muscle disc at the upper compartment Movements of TMJ; 1) Depression (opening of mouth);  It consists of 2 combined movements; 1) A hinging movement in which the head rotates downwards around a horizontal axis Hinging movement of the head at the lower compartment Posterior belly of digastric muscle Mylohyoid muscle Anterior belly of Geniohyoid muscle digastric muscle  2) A gliding movement of the head with the articular disc forwards Forward gliding movement of the and downwards below the Lateral pterygoid muscle disc at the upper compartment articular tubercle  It is done mainly by lateral pterygoid muscle, assisted by gravity  Mylohyoid, geniohyoid and digastric muscles help lateral pterygoid when the movement occurs against Hinging movement of resistance the head at the lower compartment Posterior belly of digastric muscle Mylohyoid muscle Anterior belly of Geniohyoid muscle digastric muscle Movements of TMJ (continued); 2) Elevation (closure of mouth, occlusal position); done by medial pterygoid, temporalis and masseter of both sides 3) Protrusion (forward movement); done by medial and lateral pterygoids of both sides.  Movements of TMJ (continued); 4) Retraction (backward movement); done by the posterior horizontal fibers of temporalis 5) Side-to-side (grinding or chewing movement); done by medial and lateral pterygoids of both sides acting alternately 3) Atlanto-occipital Joint Type; synovial joint, ellipsoid variety Articular surfaces; Below; superior articular facet of atlas vertebra Above; occipital condyle (N.B.) Both surfaces are covered by thin plates of hyaline cartilage. Capsule; attached to the margins of the articular surfaces 3) Atlanto-occipital Joint Ligaments; no specific ligaments, but the capsule is strengthened by its attachments to the atlanto-occipital membranes; Anterior atlanto-occipital membrane; extends from the anterior margin of foramen magnum to the anterior arch of atlas vertebra Posterior atlanto-occipital membrane; extends from the posterior margin of foramen magnum to the posterior arch of atlas vertebra  Movements; 1) Flexion and extension of the head (nodding) yes 2) Slight lateral flexion 4) Atlanto-axial Joint Type and articular surfaces; it is a complex synovial joint, consisting of 2 types of articulations; 1) Right and left lateral atlanto-axilal joints; plane synovial joints between the inferior articular facets of atlas vertebra and the superior articular facets of axis vertebra 2) Median atlanto-axial joint; pivot synovial joint between the dens (odontoid process) of axis vertebra and the fibro-osseous ring formed by the anterior arch of atlas vertebra and the transverse ligament of atlas vertebra 4) Atlanto-axial Joint Capsule; In lateral atlanto-axial joints; the joint is surrounded completely by a thin capsule In median atlanto-axial joint; there is no capsule Movements; rotatory movements of the head NO  Joints of the vertebral column [A] Joints between the vertebral bodies: these are the “intervertebral discs”, which are secondary cartilaginous joints Intervertebral (zygapophysial) joints Intervertebral discs Intervertebral disc [B] Joints between the vertebral arches: these are the “intervertebral joints”  They are formed between the superior and inferior articular processes of each two successive vertebrae.  They are synovial joints of the plane variety, allowing gliding movements during flexion, extension and rotation of the vertebral column. Intervertebral (zygapophysial) joints Intervertebral (zygapophysial) joint (opened capsule) Superior articular facets Intervertebral discs Intervertebral (zygapophysial) joints Intervertebral disc Intervertebral joint (Zygapophyseal joints) Type and variety: plane synovial joints Articular surfaces: ▪ Superiorly; inferior articular process of the vertebra above ▪ Inferiorly; superior articular process of the vertebra below Fibrous capsule: it surrounds the joint completely, and is lined by the synovial membrane Movements: gliding movements during flexion, extension and rotation of the vertebral column  Intervertebral disc (Vertebral symphysis) Type: secondary cartilaginous joint (does not ossify with age) Articular surfaces: a) Vertebral end-plates; thin layers of hyaline cartilage at Vertebral end-plate the junction of the intervertebral disc and Annulus vertebral body fibrosus Ring apophysis Intervertebral disc (Vertebral symphysis) b) Intervertebral disc;  It is absent between the 1st and 2nd cervical vertebrae, as well as between the sacral and coccygeal vertebrae.  Its thickness increases caudally, to be thickest at the lumbosacral disc  In the cervical and lumbar regions, the discs are thicker anteriorly than posteriorly, contributing to the secondary curvatures in these regions ▪ Structure of the disc; the disc consists of 2 parts; 1) Annulus fibrosus;  It is the outer lamellar part of the disc  It consists of 20 lamellae of collagen fibers.  ▪ Structure of the disc; the disc consists of 2 parts; 2) Nucleus pulposus;  It is the inner globular gelatinous part of the disc  With age, mucoid material and water content of the nucleus decreases, so it becomes stiffer and more liable for herniation under stress. Assignment 1- Enumerate the joints connecting the vertebrae and their types. 2- Describe the joint that allows rotatory movement of the skull  Topography of Lower Limb (Thigh-Gluteal region-leg-foot) Dr. Shereen Adel Professor of Anatomy & Embryology By the end of this lecture, you should be able to: By the end of this lecture the student will be able to identify: 1. Identify muscles, nerves & vessels of thigh & gluteal region. 2. Identify muscles, nerves & vessels of leg & foot. ANTERIOR COMPARTMENT OF THIGH Iliopsoas Flexors of hip: Psoas major ❑ Sartorius Iliacus ❑ Iliacus & psoas major ❑ Pectineus Sartorius Pectineus 3 Extensors of knee: ❑ quadriceps femoris 1 Rectus femoris + 3 vasti (vastus lateralis, Rectus femoris vastus medialis Vastus lateralis vastus intermedius) Vastus medialis 4 Quadriceps femoris Rectus femoris 3 Vastus intermedius Lateralis medialis All Anterior compartment muscles are supplied by femoral nerve except psoas major (supplied by lumbar plexus) 6 FEMORAL TRIANGLE It is a triangular depression infront of upper 1/3 of thigh, Just below inguinal ligament 1 2 3 4 7 5 8 6 MEDIAL COMPARTMENT OF THIGH Contains 5 muscles: -Gracillis: -3 adductors: longus, adductor brevis & adductor magnus. -Obturator externus 9 MEDIAL COMPARTMENT OF THIGH Contains 5 muscles: -Gracillis: -3 adductors: longus, adductor brevis & adductor magnus. -Obturator externus 10 3 ADDUCTORS MUSCLES of the thigh arranged into 3 layers: ❖1- Superficial → 2 Adductor Longus 1 ❖2- Middle→ 3 Adductor Brevis ❖3- deep→ Adductor Magnus 11 Nerve supply the medial compartment Obturator Nerve Blood supply the medial compartment Obturator artery & profunda femoris artery 12 The adductor canal known as subsartorial canal It is an intermuscular tunnel in the middle 1|3 of medial side of thigh It extends from apex of femoral triangle to opening in adductor magnus through which it communicate with popliteal fossa Identify the 3 marked 2 1 structure 4 14 The Gluteal region contains: 3Glutei Muscles & 6 Rotators  3Glutei 1- Gluteus maximus (superficial): extends hip – supplied by inferior gluteal n. 2- Gluteus medius (intermediate) & minimus (deep): both abduct & medially rotate hip - supplied by superior gluteal n. 3Glutei 1- Gluteus maximus (superficial): extends hip – supplied by inferior gluteal n. 2- Gluteus medius (intermediate) & minimus (deep): both abduct & medially rotate hip - supplied by superior gluteal n. Action of gluteus medius and minimus Main abductors They are important during walking and running, as they prevent tilting of the thigh of the pelvis to the unsupported raised limb.  6 lateral rotators Piriformis Obturator externus Obturator internus Superior Gemellus Inferior Gemellus Quadratus femoris 19 Nerves of the gluteal region: All are derived from SACRAL PLEXUS Ischium greater sciatic notch ischial spine lesser sciatic notch Ischial tuberosity Ischial ramus  Greater 2 Sacro- Ligaments spinous sciatic lig. foramen With 2 Foramina lesser in between sciatic foramen Sacro-tuberus ligament Muscles of the back of thigh Contains HAMSTRING MUSCLES (hip extensors & knee flexor) which are supplied by the SCIATIC NERVE & branches of profunda artery 23 Laterally medially biceps femoris 1. semitendinosus (having two (superficially) head 2. semimembranosus - long head (deep to it) - short head 3. Ischial part of adductor magnus. 24  Sciatic nerve ❑ Is the largest branch of sacral plexus & the thickest n. in the body. ❑ Descends till middle of back of thigh ❑ ends by dividing into Tibial nerve & Common peroneal nerve. 25 The safest site for intramuscular injection is the upper outer quadrant of the buttock to avoid injury of the sciatic nerve. The sciatic nerve may be injured due to : Misplaced intramuscular injection 1 4 2 3 5 6 8 7 27  POPLITEAL FOSSA A diamond shaped depression posterior to knee joint ANTERIOR COMPARTMENT OF LEG Contents : 1- Muscles: Tibialis anterior Extensor Hallucis longus Extensor Digitorum longus Peroneus tertius 2) Nerve: Anterior tibial ( deep peroneal ) nerve 3) Vessels: Anterior tibial vessels 29 ACTION Action of muscles of anterior compartment is DORSIFLEXION Dorsum of the foot Dorsal venous arch Extensor Digitorum Brevis 31 Dorsalis pedis artery It is the continuation of ant. tibial a. infront of ankle joint midway between the 2 malleoli It dips between the 1st & 2nd metatarsal bones to end in the sole of foot. LATERAL COMPARTMENT OF LEG ❑Contains 2 muscles: 1. Peroneus longus (superficial). 2. Peroneus brevis (deep). Peroneus longus Action is eversion & plantar flexion of foot. Peroneus brevis Nerve supply: Superficial peroneal nerve (one of the 2 terminal branches of common peroneal) which ends by supplying skin of most of dorsum & toes. 33  1 7 2 8 5 34 10 MUSCLES OF THE BACK OF THE LEG arranged as 2 groups DEEP SUPERFICIAL MUSCLES OF THE BACK OF THE LEG arranged as 2 groups SUPERFICIAL DEEP Gastrocnemius Popliteus Soleus Flexor digitorum longus plantaris Flexor hallucis longus Tibialis posterior  SUPERFICIAL GROUP posterior view plantaris Gastrocnemius Soleus ACHILLES TENDON Gastrocnemius, Soleus, Plantaris DEEP GROUP Popliteus Tibialis posterior Flexor digitorum Flexor longus hallucis longus  Action of superficial group 1) The superficial muscles of the (important in calf are strong plantar flexor of walking & running) ankle Joint All the muscles are supplied by Tibial nerve & posterior tibial artery popliteal tibial artery. nerve post. ant. tibial tibial artery artery posterior tibial nerve Assignment List contents of popliteal fossa List lateral rotators of the thigh Thank you 43  Muscles of Head and neck Dr. Ashraf Ramzy Professor of Anatomy & Embryology [email protected] Dr Ashraf Ramzy INTENDED LEARNING OBJECTIVES (ILO) 1. Describe the muscles of the scalp, face and muscles of mastication. 2. Describe the muscles of the neck including suprahyoid , infrahyoid muscles and prevertebral muscles. 3. Describe the triangles of the neck Muscles of Head Dr. Ashraf Ramzy Professor of Anatomy & Embryology [email protected] Dr Ashraf Ramzy  Muscles of Scalp Dr Ashraf Ramzy Occipito-frontalis Muscle * Scalp has only ONE muscle which is the occipito-frontalis muscle. * It is formed of 2 frontal bellies and 2 occipital bellies which are inserted in the epicranial aponeurosis. * Epicranial Aponeurosis: * A sheet of strong fibrous tissue on the skull cap. * Receives the insertion of the frontal and occipital bellies. Dr Ashraf Ramzy * Action of muscle: Pull the scalp backwards and raise the eyebrows thus causing the transverse wrinkles of forehead (giving expression of fear or surprise). * Nerve supply: Facial nerve. Dr Ashraf Ramzy  Muscles of Face Dr Ashraf Ramzy Muscles of Face Muscles of Facial Expressions @ General characteristics : 1. All the muscles : arise from the bones of the skull or subcutaneous tissue. 2. All the muscles : are inserted into the skin. 3. Action : they move the skin of face in the different facial expressions (therefore called muscles of facial expressions). 4. Nerve supply : all are supplied by the Facial N. (because : embryologically, they are derived from 2nd pharyngeal arch). Dr Ashraf Ramzy 5. Site : lie in the superficial fascia and there's no deep fascia in the face. (i.e. they lie subcutaneous). 6. They serve 2 main functions: a.They act as sphincters or dilators to the orifices in face which are : @ Orbit (guarded by eyelids). @ Nose (guarded by nostrils). @ Mouth (guarded by lips). b. Facial expressions and help in speaking & mastication. Dr Ashraf Ramzy  (A) Orbital Group (Muscles of Orbit & Eyelids) Orbicularis Oculi @ This is the sphincter of the eyelids (i.e. closes the eyes). @ It encircles the orbital opening. @ It consists of 3 parts : a. Orbital part: @ Action : firm closure of eyelids (for protection from dust & light). b. Palpebral part: @ action : gentle closure of eyelids (during sleeping & blinking → helps in flow of tears). c. Lacrimal part: A small part which lies medially. @ action : Dilates the lacrimal sac to help drainage of tears. @ Nerve supply of Orbicularis Oculi ms.: Facial N. Dr Ashraf Ramzy (B) Oral Group (Muscles of Lips and Cheeks) Action : 1. Prevents the accumulation of the food in the vestibule of the mouth (by pressing cheeks gainst teeth). 2.Whistling (buccina = trumpet) and blowing of air. 3.Suckling ( in babies ). Dr Ashraf Ramzy (2) Orbicularis Oris @ It is the sphincter muscle of the lips (approaches lips together & help in whistling & speech). @ It is a circular muscle around the mouth (forming ellipse around the mouth). Dr Ashraf Ramzy  Muscles of Mastication Dr Ashraf Ramzy Muscles of Mastication These are 4 muscles which arise from the skull. All are inserted into the mandible. They are: temporalis, masseter, medial pterygoid & lateral pterygoid. They are all supplied by the mandibular nerve (because all develop from 1st pharyngeal arch). All act on temporo-ma ndibular joint (TMJ). Dr Ashraf Ramzy Dr Ashraf Ramzy  Temporalis * Action: 1. Its anterior vertical fibers are strong elevator of the mandible (antigravity muscle). 2. Its posterior horizontal fibers retract the mandible (only retractor of mandible). * Nerve supply: Two deep temporal nerves from the anterior division of mandibular nerve. Dr Ashraf Ramzy Masseter * Action: 1. Its deep vertical fibers elevate the mandible (antigravity muscle). 2. Its superficial oblique fibers protrude the mandible. * Nerve supply: Masseteric branch from the anterior division of mandibular nerve. Dr Ashraf Ramzy Lateral pterygoid ** Origin : by 2 heads 1. Upper head → infratemporal crest & infratemporal surface of greater wing of sphenoid. 2. Lower head → lateral surface of lateral pterygoid plate. Dr Ashraf Ramzy  Lateral pterygoid ** Insertion: * Fovea in front of neck of mandible. * Capsule and articular disc of Temporo- mandibular joint. * Nerve supply: Nerve to lat. pterygoid from the anterior division of mandibular nerve. Dr Ashraf Ramzy Medial pterygoid ** Origin : by 2 heads 1. Superficial head (smaller): Tuberosity of maxilla. 2. Deep head (larger): Medial surface of lateral pterygoid plate. Dr Ashraf Ramzy Pterygoid Muscles ** Lateral pterygoid: 1. Depresses the mandible to open the mouth 2. Protrudes the mandible. 3. Side to side movement. ** Medial pterygoid: 1. Elevates the mandible. 2. Helps lateral pterygoid to protrude the mandible. 3. Medial and lateral pterygoid of one side acting together push mandible to the opposite side & when acting alternatively with muscles of the opposite side, they produce side to side chewing movement. Dr Ashraf Ramzy ACTION OF MUSCLES OF MASTICATION ALL MUSCLES OF MASTICATION → ELEVATE THE MANDIBLE TO CLOSE THE MOUTH, EXCEPT LATERAL PTERYGOID WHICH DEPRESSES THE MANDIBLE TO OPEN THE MOUTH. ALL MUSCLES OF MASTICATION PROTRUDE THE MANDIBLE, EXCEPT TEMPORALIS WHICH RETRACTS THE PROTRUDED MANDIBLE. Dr Ashraf Ramzy Muscles of Neck A. Sternomastoid muscle * Origin : **Sternal head → front of manubrium sterni. **Clavicular head→ medial 1/3 of clavicle. * Insertion : mastoid process. Dr Ashraf Ramzy  * Action : * One muscle bends the head to its own side & turns the face to the opposite side. * Both muscles acting together pull the head forwards & flex the neck. Dr Ashraf Ramzy * Sternomastoid divides the side of the neck into 2 triangles: 1. Anterior triangle → infront of the sternomastoid. 2. Posterior triangle → behind the sternomastoid. Dr Ashraf Ramzy B. Suprahyoid Muscles What is the Hyoid bone ? *A small U- shaped bone located just superior to the larynx. *It does not articulate with any other bone but is suspended from the skull by stylohyoid ligament. Dr Ashraf Ramzy  B. Suprahyoid Muscles 1. Digastric Muscle 1. Raises hyoid bone (during swallowing). 2. Depresses mandible (if the hyoid bone is fixed) 2. Mylohyoid Muscle 1. Elevates hyoid bone during swallowing 2. Support the floor of the mouth 3. Depresses mandible Dr Ashraf Ramzy 3. Geniohyoid Muscle * It lies deep to mylohyoid (above it ) 1. Elevates hyoid bone 2. Depresses mandible 4. Stylohyoid Muscle *A small muscle that lies along upper border of posterior belly of digastric * Action → elevates hyoid bone Dr Ashraf Ramzy C. Infrahyoid Muscles Hyoid bone * 4 muscles that lie below the hyoid Thyrohyoid bone. Omohyoid * Include: Thyroid cartilage 1. Sternohyoid. Sternothyroid 2. Omohyoid. 3. Sternothyroid. Sternohyoid 4. Thyrohyoid. Dr Ashraf Ramzy sternum  C. Infrahyoid muscles (contd.) * @ All infrahyoid muscles depress the hyoid bone. Dr Ashraf Ramzy D. Prevertebral muscles *Are 4 muscles that cover the front of the vertebral cloumn. *They extend from the base of the skull to the thorax. *Their nerve supply is by cervical nerves. Dr Ashraf Ramzy D. Prevertebral muscles (contd.) * They include: 1. Rectus capitis lateralis. 2. Rectus capitis anterior. 3. Longus capitis. 4. Longus colli (cervicis). Dr Ashraf Ramzy  F. Muscles of Pharynx I. The 3 constrictors: * Have the same insertion (into pharyngea Raphe) but have different origins. l 1. Superior constrictor (SC) : 2. Middle constrictor (MC) : 3. Inferior constrictor (IC) : SC * Action of constrictors: MC They contract to constrict the pharynx to push the bolus of the food downwards IC towards the oesophagus. Dr Ashraf Ramzy II. The 3 longitudinal muscles : * All have the same insertion → thyroid cartilage , but they have different origins : 1. Stylopharyngeus : arises from styloid process. 2. Palatopharyngeus : arises from soft palate. 3. Salpingopharyngeus : arises from the wall of eustachian (auditory) tube. * Action: They pull larynx & pharynx upward during swallowing to close the laryngeal inlet. Dr Ashraf Ramzy Assignment 1- Describe the muscles of Lips and Cheeks. 2- Enumerate the suprahyoid muscles and their nerve supply 3- Enumerate the muscles of mastication and their action 4- Enumerate the subdivisions of the anterior triangle and their boundaries. Dr Ashraf Ramzy  INTENDED LEARNING OBJECTIVES (ILO) 1. Describe the muscles of the posterior abdominal wall. 2. Describe the muscles of the thoracic wall. 3. Describe the anatomy of the diaphragm 1) Psoas Major Muscle Origin: a) By 5 digitations from the sides of the thoracolumbar and upper 4 lumbar intervertebral discs, as well as the adjacent margins of the vertebral bodies b) From the tendinous arches connecting upper and lower borders of lumbar vertebrae over the lumbar arteries c) From the anterior surfaces of the lumbar transverse processes Insertion; it joins iliacus muscle to form together iliopsoas tendon, which is inserted into the lesser trochanter of femur. Nerve supply; ventral 1ry rami of L2, 3, 4 Action; with iliacus muscle (discussed later)  Medial arcuate ligament of diaphragm (thickening of uppermost part of psoas fascia) Quadratus lumborum muscle Psoas minor muscle Psoas major muscle Iliacus muscle 2) Psoas Minor Muscle This muscle is present in 60% of individuals. Origin: from T12 and L1 vertebrae and the disc in-between Insertion; into the ilio-pectineal eminence Nerve supply; ventral 1ry ramus of L1 Action; weak flexion of the vertebral column 3) Iliacus Muscle Origin; it arises from the upper 2/3 of the iliac fossa. Insertion; it joins psoas major muscle to form together iliopsoas tendon, which is inserted into the lesser trochanter of femur. Nerve supply; from the femoral nerve Action of iliacus and psoas major (ilio-psoas muscle) 1) Acting from its origin, it produces flexion and medial rotation of the thigh (it is the main flexor of the hip joint). 2) Acting from its insertion, it flexes the trunk forwards over the thigh.  4) Quadratus Lumborum Muscle Origin; from the iliolumbar ligament and adjacent 5 cm of the iliac crest. Insertion; a) Into the tips of transverse processes of upper 4 lumbar vertebrae b) Into the medial ½ of the lower border of 12th rib Nerve supply; ventral 1ry rami of T12 and upper 4 lumbar nerves Action; 1) It fixes the 12th rib, thus providing a fixed point for efficient contraction of the diaphragm. 2) Contraction of one muscle causes lateral flexion of the vertebral column on its side. A)Muscles connecting the ribs to the vertebral column  Serratus posterior superior  Serratus posterior inferior  Levatores costarum B)Muscles connecting the ribs to the sternum Sternocostalis muscle  Sternocostalis muscle Subcostalis muscle C) Muscles connecting the ribs together  External intercostal muscles (11 pairs)  Internal intercostal muscles (11 pairs)  Innermost intercostal muscles (11 pairs)  Subcostales D) Muscle separating thoracic cavity from the abdominal cavity; Intercostal muscles  Diaphragm  External intercostal muscle Intercostal muscles 1) External intercostal muscles Direction of fibers; downwards, forwards, and medially Vertical follow up; from lower Anterior intercostal border of the rib above to upper membrane border of the rib below Horizontal follow up; from the tubercle of the rib posteriorly to the costochondral junction anteriorly, then it is replaced by the External intercostal external (anterior) intercostal muscle membrane, which extends to the side of the sternum Internal intercostal muscle 2) Internal intercostal muscles Direction of fibers; downwards, backwards, and laterally Vertical follow up; from the floor of the costal groove of the rib above to the upper border of the rib below Horizontal follow up; from the side of the sternum anteriorly to the angle of the rib posteriorly, then it is replaced by the internal (posterior) intercostal membrane Internal intercostal muscle Posterior intercostal membrane Innermost intercostal muscle 3) Innermost intercostal muscle