Week 3 Skeletal System PDF

Skeletal System Dr. Atyman alsheikh 1  THE SKELETON Skeleton means dead body It is composed of * 206 bones, * joints * ligaments * cartilage found in nose, ribs, joints, vertebral discs, etc. It is consisted of: - Axial skeleton...

Skeletal System Dr. Atyman alsheikh 1  THE SKELETON Skeleton means dead body It is composed of * 206 bones, * joints * ligaments * cartilage found in nose, ribs, joints, vertebral discs, etc. It is consisted of: - Axial skeleton is composed of skull, vertebral column and bony thorax. - Appendicular skeleton consists of upper and lower limbs, and pectoral (shoulder) and pelvic (hip) girdles. Dr. Atyman alsheikh 2 Dr. Atyman alsheikh 3 I. Axial Skeleton 1. Skull.  It is made up of - 22 bones distributed within Cranium and Facial bones. - many smaller cavities such as inner ear, nose, eyes, etc.. - 85 openings as foramina, fissures canals. Dr. Atyman alsheikh 4 Frontal view Dr. Atyman alsheikh 5 Frontal view Lateral View Posterior View inferior View 6 Dr. Atyman alsheikh A. Cranium :  Forms most of the skull formed of * vault ( forms superior, lateral and posterior aspects and forehead) * base (forms the inferior aspect).  Consists 6 types of 8 bones ◦ Frontal (1) ◦ Parietal (2) ◦ Temporal (2) ◦ Occipital (1) ◦ Sphenoid (1) ◦ Ethmoid (1) Dr. Atyman alsheikh 7 1. Frontal: forms - the anterior portion of the cranium, - forehead, 2. Parietal bones form - the superior and lateral aspects of the skull. - several sutures with other bones: a. Coronal suture lies between the frontal and parietal b. Sagittal suture joins both parietal bones c. Lambdoidal suture links occipital with parietal d. Squamosal suture ties temporal with parietal e. Occipitomastoid suture connects occipital with mastoid portions of temporal. Dr. Atyman alsheikh 8  sutures Squamousal suture Dr. Atyman alsheikh 9 3. Temporal bones - named due to grey hair appearance in this area. - Consist of several regions; - squamous - tympanic - zygomatic process - styloid - mastoid 10 Dr. Atyman alsheikh Temporal bone regions Dr. Atyman alsheikh 11 4. Occipital bone - Form the lower posterior wall and base of the skull. - Two Occipital condyles - Foramen magnum through which the inferior part of the brain connects with the spinal cord Dr. Atyman alsheikh 12 5. Sphenoid: - butterfly shape - keystone of the cranium because it articulates with all cranial bones. - It consists of a. central body b. three pairs of processes: * wings (greater and lesser) * pterygoid. c. saddle like depression called sella torcica that contains the pituitary gland. d. It has also many foramina as, optic, ovale, etc…. Dr. Atyman alsheikh 13 6. Ethmoid : complicated irregular bone lies between sphenoid and nasal bones. Dr. Atyman alsheikh 14 B. Facial bones - Perform many functions * face framework, * provide cavities of sense organs, air and food passages, * teeth borning * anchor facial muscles. - Include 8 types of 14 bones * maxilla (2) * mandible * zygomatic (2) * nasal (2) * lacrimal (2) * palatine (2) * inferior nasal conchae (2) * vomer Dr. Atyman alsheikh 15 Dr. Atyman alsheikh 16 1. Maxilla bones - Form: * upper jaw, * orbital floor * mouth roof * sideway of the nose - Contain infraorbital foramen. Dr. Atyman alsheikh 17 2. Mandible; - U-shape, - the largest and strongest bone in the face that forms lower jaw. - It forms with temporal bones the movable joints of the skull. Dr. Atyman alsheikh 18 3. Zygomatic bones; shape the cheek and the outer margin of the orbit. 4. Nasal bones: form the upper part of the nose where the cartilage forms the lower part. 5. Lacrimal bones; forms the nasal cavity and median wall of the orbit. Dr. Atyman alsheikh 19 6. Palatine bones:  2 L-shape, form with palatine process of maxilla the hard palate. Dr. Atyman alsheikh 20  7. Inferior nasal conchae bones; form lateral wall of nasal cavity 8.Vomer bone; slender shape forms part of the nasal septum. 21 Dr. Atyman alsheikh Special characteristics of orbits , nasal cavity, paranasal sinuses and hyoid bone * Orbits; - Bony cavities of eyes are. > Seven bones :(frontal, sphenoid, zygomatic maxilla, palatine, lacrimal and ethmoid) * Nasal cavity; five bones (ethmoid, palatine, inferior nasal conchae, maxilla, and vomer) * Paranasal sinuses; five bones (frontal, sphenoid, ethmoid, 2 maxilla) to form 4 sinuses (frontal, ethmoid, sphenoid and maxillary). -These sinuses enhance the resonance of voice. Dr. Atyman alsheikh 22 paranasal sinuses Dr. Atyman alsheikh 23 Hyoid bone - U-shaped, - located above the larynx and below the mandible. - it is suspended from the styloid process by ligaments - It is the only bone that doesn’t articulate with any other bone. - It controls the movement of tongue and larynx during swallowing and speech. Dr. Atyman alsheikh 24 2. Vertebral column - Known as spine, backbone or spinal canal. - Consist of 33 bones (vertebrae) in childhood and become 26 in adulthood. - Divided into 5 regions * cervical (7), * thoracic (12), * lumbar(5), * sacral (5 bones fused at age 16-25), * coccyx (4 fused bones). - Vertebrae are fastened by ligaments and intervertebral discs. Dr. Atyman alsheikh 25 - Normal curvatures * S shape * (cervical, thoracic, lumbar and sacral) * increase resilience and flexibility of the spine - Abnormal curvatures due to *congenital, * disease, * posture or unequal muscles. * examples of these abnormal curvatures: - Scoliosis: lateral curvature in thoracic region - Kyphosis: dorsal curvature in thoracic region - Lordosis: in lumbar region Dr. Atyman alsheikh 26 Abnormal curvatures Dr. Atyman alsheikh 27 Vertebral column Dr. Atyman alsheikh 28  Characteristics of Vertebrae - A typical vertebrum consists of:. centrum (body),. vertebral arches,. spinous and transverse processes. vertebral foramen - All have:. flat rounded body,. spinous and transverse processes( except the first),. foramen (except sacrum and coccyx) Dr. Atyman alsheikh 29 - The first cervical vertebra is called atlas, - The second is axis. - Thoracic vertebrae have articular facet for ribs - Vertebrae articulate with each other by fibrocartilage ligaments and joints, in addition to articular processes. Dr. Atyman alsheikh 30 Dr. Atyman alsheikh 31  Sacral and Coccyx sacral hiatus appears dorsally and it is region for sacral anesthesia Dr. Atyman alsheikh 32 3.The Bony Thorax (Rib Cage) A. Sternum: * known as breast bone, * dagger (knife) shape * Three bones (manubrium, body and xiphoid). - Manubrium: the upper part articulate with the clavicle (a bone of pectoral girdle) and the first two ribs. -The body: Midportion articulates with the 2nd to seventh rib. - Xiphoid: Small, inferior end of the sternum. Serve as attachment with diaphragm and some abdominal muscles. Dr. Atyman alsheikh 33 B. Ribs - Twelve pairs of ribs with vertebral column and sternum shape the thoracic cavity. - Each rib articulates with both the body and transverse process of its corresponding thoracic vertebrum. - Ribs 1 through 7 join a costal cartilage which attaches it to the sternum (true ribs). - the 8th to 10th join the cartilage of the true ribs and indirectly attached to the sternum known as false ribs. -The 11th and 12th ribs are not attached to the sternum known as floating ribs. Dr. Atyman alsheikh 34 Thoracic cage Dr. Atyman alsheikh 35 II. The Appendicular Skeleton -It is composed of - Girdles ( Pectoral and Pelvic) - Limbs (Upper and Lower) attached to these girdles respectively. Dr. Atyman alsheikh 36 Dr. Atyman alsheikh 37 1. Pectoral Girdles and Upper Limbs; A. Pectoral Girdle: - It consists of Clavicle and Scapula - Clavicle is slender doubly curved. It is attached to the sternum by sternal end and to the scapula by acromial end. - Scapula is a triangular flat bone. It has borders, projections, and processes. - One of the borders forms the Glenoid cavity where the head of the humerus bone fits in - one of the projection is Acromion which allow clavicle to attach. Dr. Atyman alsheikh 38 Dr. Atyman alsheikh 39 B. Upper Limb: - Made up of Arm, Forearm, and Hand. - Arm consists a long bone (Humerus) which has a head articulate with Glenoid cavity at the proximal end. > However, two Epicondyles and one Trochlea at the distal end. > Median epicondyle makes the protrusion of the elbow at the anterior view Dr. Atyman alsheikh 40 Forearm includes two parallel bones Radius and Ulna. * Radius is found on the Thumb side with a nail-shaped end. Ulna, is found on the little finger side. It is longer than radius and forms the Elbow joint with humerus (Olecranon process) Dr. Atyman alsheikh 41 - Hand is composed of Wrist, Palm and Fingers. * Wrist (Carpal) consists of 8 bones bound closely and firmly by ligaments. * Palm (Metacarpal) consists of 5 bones. * Fingers(Phalanges): each finger consistsof 3 bones (distal, middle and proximal) except the thumb (2 bones) Dr. Atyman alsheikh 42 Dr. Atyman alsheikh 43  Upper limb Dr. Atyman alsheikh 44 2. Pelvic Girdle and Lower Limb A. Pelvic Girdle: -It is formed by a pair of Coxal bones unit with each other anteriorly by pubic symphysis and with sacrum posteriorly by sacroiliac joint - Coxal bone comprises three bones: - Ilium, Ischium and Pubis. - These bones joined together to form a deep hemispherical socket called Acetabulum that articulate with the head of femur bone of the thigh. Dr. Atyman alsheikh 45 Dr. Atyman alsheikh 46 B. Lower Limbs; - They are made up of Thigh, Leg and Foot. - Thigh consists of a Femur bone ( largest, longest and strongest in the body). - it is organized to have * Head, Neck and Trochanter at the proximal end * Condyle and Patellar surface at the distal end. Dr. Atyman alsheikh 47 Femur Dr. Atyman alsheikh 48 - Leg is formed by two bones (Tibia and Fibula): * Tibia is larger, stronger and superficially located of the two bones. It articulate with the femur to form the Knee joint. However, the distal end form the medial ankle bulge * Fibula is smaller and more deep and articulate with tibia. It forms the Lateral Ankle bulge. Dr. Atyman alsheikh 49 Tibia and Fibula Dr. Atyman alsheikh 50 - Patella is a triangle sesamoid bone guard the knee joint and improve the raising up of thigh muscle Dr. Atyman alsheikh 51 - Foot consists of Tarsus, Metatarsus and Toes. * Tarsus is made of 7 bones. Among these, - Calcaneus bone forms the Heel and carry the talus on its superior surface. - Achilles tendon join the calf muscle with calcaneus bone. * Metatarsus includes 5 bones * Toes (phalanges): each involves 3 bones except the great toe (2 bones) Dr. Atyman alsheikh 52 Foot Dr. Atyman alsheikh 53  Complete lower leg Dr. Atyman alsheikh 54  Three Arches of the foot include : - Lateral longitudinal, Medial longitudinal and transverse arches - Elasticity of the arches absorbs the pressure - NOTEBY: Strong ligaments and tendons normally hold the foot bones in their arch positions. However, if they are weaken arch will be flattened and resulted in flat foot. Dr. Atyman alsheikh 55 Arches of foot Dr. Atyman alsheikh 56  Developmental Aspect of the Skeleton.  Skull bones of newborn infant are incomplete and connected by unossified fibrous membranes known as fontanels. These fontanels allow the infant head to be compressed during birth, and accommodate brain growth.  Four fontanels can be detected: anterior (between frontal and parietal), posterior (Parietal and occipital), sphenoid and mastoid fontanels. Dr. Atyman alsheikh 57 Fontanels Dr. Atyman alsheikh 58  Herniation  Old ages affect many parts of skeleton especially the spine. ◦ Water contents of the vertebral discs declines which results in hernia (disc slipping).  Herniation could be developed due trauma which ruptures the annulus fibrous of the disc causing protrusion of nucleus pulposus of the disc toward spinal cord and spinal nerves.  Treated by: -bed rest, surgical, or enzymatic drug (chymopapain) Dr. Atyman alsheikh 59 Intervertebral disc herniation Dr. Atyman alsheikh 60  There are several differences between skeleton in male and female Character Male Female General skeleton Larger, heavier, less Smaller, lighter, more tilted forward tilted to be adapted for childbearing Pubic angle More acute 50-60 º Broad 80-90º Sacrum Narrow and larger Wider and shorter Pelvic brim Narrow, heart shape Wide, oval shape Pelvis in general Deep, funnel shape with Shallow, board, wider narrow pubic arch arch Dr. Atyman alsheikh 61  female male Brim, angle Sacraum, coccyx Inferior view Dr. Atyman alsheikh 62 Changes throughout age Dr. Atyman alsheikh 63