Introduction to general anatomy of bones.pdf

Anatomical Overview of bones & Skeletal system  Objectives Define the musculoskeletal system ✓ Enlist the different function of the skeletal system ✓ To define the important functions of the bone ✓ To discuss the major classification of bones & skeletal ✓ To describe the overall structure of axial...

Anatomical Overview of bones & Skeletal system  Objectives Define the musculoskeletal system ✓ Enlist the different function of the skeletal system ✓ To define the important functions of the bone ✓ To discuss the major classification of bones & skeletal ✓ To describe the overall structure of axial and appendicular skeleton ✓ To discuss the detail anatomy of skull ✓ What is the bone marking and its importance ✓ The human musculoskeletal system is an organ system that gives humans the ability to move using their muscular and skeletal systems. The musculoskeletal system provides form, support, stability, and movement to the body. It is made up of : the bones of the skeleton, muscles, cartilage, tendons, ligaments, joints, and other connective tissue that supports and binds tissues and organs together. Bone Os (L),Osteon (G), osteology, ossification, osteomyelitis, osteomalacia, osteoma, osteotomy Bone is the substance that forms the skeleton of the body. Bone is a living tissue capable of changing its structure as the result of the stresses to which it is subjected. Like other connective tissues, bone consists of cells, fibers, and matrix. Bone is hard, because of the calcification of its extracellular matrix and possesses a degree of elasticity because of the presence of organic fibers. It houses and protects within its cavities the delicate blood-forming bone marrow.  Types of bone 1- According to structure A- Compact bone-----form hard layer B- Spongy bone form inner delicate trabeculated layer 2- According to morphology;(shape): Long, short, flat, irregular 3- According to development: A- Membranous which develop in dense membranes of mesodermal tissues B- Cartilage bone… develop in cartilaginous models  1- According to structure Outer layer Inner layer  2- According to morphology;(shape): 1-Long Bone 2-Short Bones. Generally, cube shape Equal length and width A part of the skeleton is intended for strength and compactness combined with limited movement. These consist of cancellous tissue covered by a thin crust of compact substance. EX: the carpus of hand and - tarsus of foot.  vertebra Skull Hip bone  cranium sternum EX: cranium- sternum- scapula scapula Sesamoid Bones Sesamoid bones are small nodules of bone that are found in certain tendons where they rub over bony surfaces. The greater part of a sesamoid bone is buried in the tendon, and the free surface is covered with cartilage. The largest sesamoid bone is the patella, which is located in the tendon of the quadriceps femoris. Other examples are found in the tendons of the flexor pollicis brevis and flexor hallucis brevis. The function of a sesamoid bone is to reduce friction on the tendon; it can also alter the direction of pull of a tendon. Practice Bones are often classified according to their shape and/or developmental pattern. Which of the following choices is an example of a flat bone? (A) Humerus (B) Sternum (C) Hamate (D) Maxilla (E) Patella  Surface Marking of bones The surfaces of bones show various markings or irregularities. Where bands of fascia, ligaments, tendons, or aponeuroses are attached to bone, the surface is raised or roughened. They appear at puberty and become progressively more obvious during adult life. The pull of these fibrous structures causes the periosteum to be raised and new bone to be deposited beneath. In certain situations, the surface markings are large and are given special names. Bone Marking Condyle: rounded articular area (e.g., condyles of the femur). Crest: ridge of bone (e.g., iliac crest). Epicondyle: eminence superior to a condyle (e.g., epicondyles of the humerus).  Bone Marking Facet: smooth flat area, usually covered with cartilage, where a bone articulates with another bone (e.g., articular facets of a vertebra). Foramen: passage through a bone (e.g., obturator foramen). Fossa: hollow or depressed area (e.g., infraspinous fossa of the scapula). Bone Marking Line: linear elevation (e.g., soleal line of the tibia). Malleolus: rounded prominence (e.g., lateral malleolus of the fibula). Bone Marking Notch: indentation at the edge of a bone (e.g., greater sciatic notch in the posterior border of the hip bone). Process: projecting spine-like part (e.g., spinous process of a vertebra). Bone marking Protuberance: projection of bone (e.g., external occipital protuberance of the cranium). Spine: thorn-like process (e.g., spine of the scapula). Trochanter: large blunt elevation (e.g., greater trochanter of the femur). Bone Marking Tubercle: small raised eminence (e.g., greater tubercle of the humerus). Tuberosity: large rounded elevation (e.g., ischial tuberosity). (206) Practice Cranial Bones Axial skeleton (80 BONES) Parietal (2) Temporal (2) Vertebral Column Frontal (1) Cervical vertebrae (7) Occipital (1) Thoracic vertebrae (12) Ethmoid (1) Lumbar vertebrae (5) Sphenoid (1) Sacrum (1) Coccyx (1) Facial Bones Thoracic Cage Maxilla (2) Sternum (1) Zygomatic (2) Ribs (24) Mandible (1) Nasal (2) Platine (2) Inferior nasal concha (2) Lacrimal (2) Vomer (1) auditory Ossicles Malleus (2) Incus (2) Stapes (2) Hyoid (1)  The Skull  The skull protects  The brain  Entrances to respiratory system  Entrance to digestive system  The skull contains 22 bones 8 cranial bones:  Form the braincase or cranium  14 facial bones:  Protect and support entrances to digestive and respiratory tracts  The bones of human skull are divided into two parts: the neurocranium and the viscerocranium. Viscerocranium (Face): Consists of 14 bones (2) Maxilla (2) Zygomatic bones (2) Lacrimal bones (2) Palatine bones (2) Nasal bones (2) Inferior nasal conchae (1) Vomer (1) Mandible  Neurocranium: Consists of 8 bones (1) Frontal Bone (2) Temporal Bones (2) Parietal Bones (1) Occipital Bone (1) Sphenoid Bone (1) Ethmoid Bone 31 Frontal Bone The large bone that makes up the forehead. Landmarks: Squama: flat portion that forms the forehead Supraorbital margin Supraorbital foramen: for blood vessels and nerves Frontal sinuses: hollow spaces behind the squama.  Frontal Bone Frontal bone  Temporal Bones A large irregular bone situated at the base and side of the skull. The temporal bone is connected with the mandible (the jaw bone) via the temporomandibular (TM) joint. The temporal bone is formed of three parts (squamous, tympanic and petrous). Landmarks: Squama: Zygomatic process Petrous portion: Mandibular fossa: articulates with the condyle of the mandible (TMJ) External auditory meatus Mastoid process: Styloid process Temporal Bones Squamous Zygomatic process Mastoid External acoustic meatus Styloid process 35 Temporal bone Mandibular fossa Petrous part 36  Parietal Bones The main bone on the side of the skull. It articulates (joins) with: - the other parietal bone , - the frontal bone , - the occipital, and - the sphenoid and temporal bones Parietal Bone (Lateral View) (Red Colored Bone)  Occiput The occipital bone articulates (joins) with the parietal, temporal and sphenoid bone of the skull, and the first cervical vertebra (the atlas). Landmarks: Foramen magnum: large hole, allowing passage of the spinal cord External occipital protuberance Nuchal lines: a superior and inferior line running laterally from the midline. Occiput 40 Sphenoid Bone A prominent, irregular bone at the base of the skull. " Landmarks Greater wings: large lateral projections of bone Lesser wings: smaller lateral projections of bone above the greater wings Pterygoid processes Sella turcica: cradles the pituitary gland. Sphenoid Bone (Lateral View) (Green Colored Bone) 42 Sphenoid Bone 43 Ethmoid Bone An irregularly shaped, spongy bone that provides the floor of the front part of the skull and the roof of the nasal cavity. Landmarks: Lateral masses: form most of the wall between the nasal cavity and the orbits Perpendicular plate: Cribiform plate: Olfactory foramina: Nasal concha Important landmarks on The Bones of the Face  Maxilla The largest bones of the face, except for the mandible and form, by their union, the whole of the upper jaw. They hold the upper teeth, and connect to the zygomatic bones (cheek bones). Landmarks: Infra Orbital foramen: Alveolar process: containing the upper teeth Palatine process: forming the anterior ¾ of the hard palate. Maxilla Palatine process  Mandible Largest and strongest bone of the face. Forms the lower jaw. Landmarks: Body Rami: Angle of the mandible Condylar process: articulates with the mandibular fossa of the temporal bone. Coronoid process Alveolar process: arch of bone containing the lower teeth Mental foramen: small hole on the side of the body for blood vessels and nerves. Mandibular foramen: for blood vessels and nerves 49 Normas of skull Norma verticalis Norma frontalis Norma lateralis Norma occipitalis Norma basalis externa Norma basalis interna  Norma verticals It show 3 skull sutures which are: Coronal Sagittal Lambdoid Norma frontalis Contains 2 orbital cavities Nasal cavity Norma lateralis The lateral aspect of the cranium is formed by both the neurocranium and the viscerocranium The main features are: the temporal fossa and the infratemporal fossa. Norma lateralis Norma occipitals Norma basalis externa Norma basalis interna The internal surface of the cranial base has three large depressions that lie at different levels: the anterior, middle, and posterior cranial fossae. 57  Anterior cranial fossa Middle cranial fossa Posterior cranial fossa 58  Foramina/Apertures Foramina in Anterior Foramina in Middle Foramina in Posterior cranial fossa cranial fossa cranial fossa Cribriform foramina in 1- Optic canals 1- Foramen magnum cribriform plate 2- Superior orbital fissure 2- Jugular foramen 3- Foramen rotundum 3- Hypoglossal canal 4- Foramen ovale 5- Foramen spinosum 6-Foramen lacerum Anterior view Figure 7.3d ▪ the sutures of skull ▪ Lambdoid ▪ Coronal ▪ Sagittal ▪ Squamous The Adult Skull – lateral view Tympanic region of temporal bone Figure 7.3c Cranium, superior view Inferior view.The Adult Skull, inferior Figure 7.3e Basalis interna Lesser wing Greater wings Figure 7.4b Paranasal Sinuses Hollow portions of bones surrounding the nasal cavity Functions of paranasal sinuses: Lighten the skull Give resonance and amplification to voice Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Fracture of the skull appears like this  Thoracic cage  Thoracic vertebrae  Ribs  Sternum  Ribs and sternum forms the rib cage  Ribs  Ribs 1-7 are attached to vertebrae (“true ribs”)  8-12 are attached to the cartilage of the 7th rib (“false ribs”)  11-12 are floating ribs  Typical rib: Has a head, neck, tubercle and a body Costal groove marks pathway of blood returning  to the heart Sternum It consist of :  Manubrium  Body  Xiphoid process  Vertebral column  Vertebrae, sacrum, coccyx  7 cervical vertebrae  12 thoracic vertebrae  5 lumbar vertebrae  Sacrum and coccyx are fused vertebrae  Typically has a body and vertebral arch  Superior and inferior articular processes  Separated by intervertebral discs THE UPPER LIMBS BONES The bones of the upper limb include ; the clavicle, scapula, humerus, radius, ulna, Carpal bones Metacarpals, phalanges (proximal, middle, and distal) THE LOWER LIMBS BONES The bones of the lower limb include: the hip (coxal) bone formed by the fusion of the ilium, ischium, and pubis; femur; patella; tibia; fibula; tarsal bones metatarsals; phalanges (proximal, middle, and distal) Clinical anatomy Fracture Fracture is a break in the continuity of a bone. The fracture which is not connected with the skin wound is known as simple (closed) fracture. The fracture line may be (a) oblique or (b) horizontal. The fracture which communicates with the skin wound is known as (c) compound (open) fracture. Hanging till death" occurs due to fracture of dens of " axis vertebra  Practice A 16-year-old boy crashes his mountain bike and suffers a fractured tibia. Which of the following damaged structures would most likely produce the acute pain emanating from the fractured tibia? (A) Nerves in compact bone (B) Nerves in trabecular bone (C) Surrounding muscle and tendon receptors (D) Periosteal nerves (E) Vascular nerves