Bones of the Skeleton 2025 PDF

Bones Of skeleton Dr. Anfal M. Elawady Assistant lecturer of anatomy & embryology Faculty of medicine, Suez University 1  Hello! Contact Information: Dr. Anfal El-awady Mobile: 01030469231 Official Email: [email protected] 2 I...

Bones Of skeleton Dr. Anfal M. Elawady Assistant lecturer of anatomy & embryology Faculty of medicine, Suez University 1  Hello! Contact Information: Dr. Anfal El-awady Mobile: 01030469231 Official Email: [email protected] 2 Intended Learning Outcomes: (ILOs) 1- Classify bones according to position, structure, shape and development. 2- Describe the general structure, parts and blood supply of a long bone. 3 Classification of bones 4  Axial skeleton 5  Skeleton ❖ About 206 bones Region of Skeleton No of Bones Axial skeleton Skull Cranium 8 Face (+ mandible) 14 Auditory ossicles 6 Hyoid 1 Vertebrae (including sacrum and coccyx) 26 Sternum 1 Ribs 24 6 Appendicular skeleton 7 Appendicular skeleton Shoulder girdles Clavicle 2 Scapula 2 Upper extremities Arm: Humerus 2 Forearm: Radius 2 Ulna 2 Hand: Carpals 16 Metacarpals 10 Phalanges 28 8 Appendicular skeleton Pelvic girdle Hip bone 2 Lower extremities Thigh: Femur 2 Leg: Patella 2 Fibula 2 Tibia 2 Foot: Tarsals 14 Metatarsals 10 Phalanges 28 9  TYPES OF BONES A- According to position: Axial skeleton Appendicular skeleton ○ The skull ○ Upper limb ○ Vertebral column ○ Lower limb ○ Thoracic cage 10 11  Axial skeleton 1-The skull Neurocranium: ○ Bones of the skull base and calvarium that covers the brain. Viscerocranium: ○ Bones of the face 12  2-Vertebral column ○ Formed of 33 or 26 vertebrae. ○ Separated intervertebral discs. ○ Classified into: 7 Cervical vertebrae. 12 Thoracic vertebrae. 5 Lumbar vertebrae. 5 Sacral vertebrae. (Fused to form 1 sacrum). 4 Coccygeal vertebrae (Fused to form 1 coccyx). ○ The skull articulates with the first cervical vertebra (Atlas). 13 3- Thoracic cage ○ Formed of: Anterior: The sternum that formed of three parts: Manubrium sterni (upper part) Body (middle part) Xiphoid process (lower part) Posterior: 12 thoracic vertebrae & intervertebral discs. On each side: 12 ribs & their costal cartilages. 14  Appendicular skeleton Part Upper limb Lower limb Girdle Clavicle-scapula Hip bone Proximal segment Humerus Femur Middle segment Radius-ulna Tibia-fibula Distal segment Carpus (8) Tarsus (7) Metacarpals (5) Metatarsals (5) Phalanges (3 for each finger, Phalanges (3 for each toe, 2 for the thumb) 2 for the big toe) 15 16  Appendicular skeleton Axial skeleton Shoulder girdles Pelvic girdle The skull Clavicle Hip bone - Cranium Scapula - Face (+ mandible) Lower extremities Vertebral column Upper extremities Thigh: 7 Cervical Arm: Femur 12 Thoracic Humerus Leg: 5 Lumbar Forearm: Fibula 5 Sacral (Fused → 1 sacrum) Radius Tibia 4 Coccygeal (Fused →1 coccyx) Ulna + Patella Thoracic cage Hand: Foot: Anterior: sternum Carpals Tarsals Manubrium sterni → upper part Metacarpals Metatarsals Body → middle part Phalanges Phalanges Xiphoid process → lower part On each side: 24 ribs & their costal cartilages 17 Posterior: ?! 19 B- According to structure: Compact bone Cancellous (Spongy) bone ○ Solid and compact ○ Thin irregularly arranged branching bone trabeculae. ○ Outer layer of flat and short bones and cylinders of long bones ○ Separated by bone marrow spaces ○ - Diploe of flat bones (skull) - Inner mass of short bones - Terminal ends of long bones 21 22  C- According to shape: 1- Long bones: as femur & humerus. 7- ±Sutural bones 2- Short bones: as carpal & tarsal bones. 3- Flat bones: as scapula & bones of skull cap. Sesamoid bones Short bones 4- Irregular bones: as vertebrae & bones of the base of skull 5- Sesamoid bones: small bones found in certain tendons as the patella. 6- Pneumatic bones: Bones contain small air cavities as paranasal sinuses 23 1- Long bones (2 ends & 1 shaft): as all bones of (Limbs) + Long = cLavicLe → carpals & tarsals ‫هشيل‬ 2- Short bones: as carpal & tarsal bones. (Sprain wrist & ankle) 3- Irregular bones: as (I) →Mandible ‫ شرطة فوق‬, hip bones ‫ & شرطة تحت‬vertebrae ‫مابينهم خط بالطول‬ 4- Sesamoid bones : small bones found in certain tendons as the patella. (Pea-shaped as Patella) Flat bones ‫ العضم الباقى‬as Skull cap ‫فوق‬ Sternum ‫ادام‬ Scapula ‫ورا‬ Ribs ‫مابينهم ع الجنب‬ ❖ Axial skeleton: (Ribs, sternum, vertebrae + hip bone): → cartilaginous ossification ❖ All long bone → cartilaginous ossification except (the double L) → CLavicLe (membranous 24 ossification) 25 D- According to development: Membranous bone Cartilaginous bone ○ Membrane is changed to bone. ○ Cartilage is changed to bone. ○ Through membranous ossification ○ Through cartilagenous ossification ○ e.g., Flat bone as skull cap, clavicle ○ e.g.: Long bones, except clavicle. 26 Which of the following bones is considered as a long bone? a. Skull cap b. Vertebra c. Femur d. Carpals Which of the following bones developed through cartilagenous ossification? a. Skull cap b. Humerus c. Scapula d. Clavicle 28 29  Long Bone Parts of long bone Every long bone has two ends and one shaft: Epiphysis → The ends. Diaphysis → The shaft. Epiphyseal cartilage(line/plate) →between the epiphysis and diaphysis → during the growing phase. → allows the bone to increase in length →replaced by bone and the growth stops Metaphysis → part of the diaphysis adjacent to epiphyseal cartilage. 30  Structure of long bones The shaft The ends ○ Having a cavity called marrow ○ Formed of cancellous bone cavity ○ Surrounded by a thin layer ○ The wall of the shaft is formed of compact bone. of compact bone ○ The articular surface of the ○ Covered by a connective tissue bones is covered by hyaline sheath called the periosteum. cartilage 31  Blood supply of long bones 1. Nutrient artery: Bone marrow, branches in metaphysis. 2. Epiphyseal artery: Epiphysis 3. Metaphyseal artery: Metaphysis 4. Periosteal artery: Periosteum. N.B: Cartilaginous epiphysis hyaline cartilage has NO blood supply 32  BONE MARROW 1. Red bone marrow: - Forms red blood cells. - Lies in: Skull, vertebrae, ribs, sternum, hip, upper end of humerus, femur (spongy bone) 2.Yellow (inert) bone marrow: - Is composed of fatty tissue in the medullary cavity. 33 35 Thank you! 36