Overview of the Skeleton 1 The skeletal system includes Bones of the skeleton Cartilages, ligaments and other connective tissues that stabilize and connect 2 Functions of the skeletal system Support Storage of minerals and lipids Blood cell production Protection Leverage 3 Subdivisions of the skeleton Axial Lies around the body’s center of gravity Appendicular Limbs 4 Bone structure = two types of bone Compact bone (dense) Spongy bone (cancellous) trabecula 5 Classification of bones By the shape Long Flat Short Irregular Sesamoid Sutural 6 Classification of bones 7 Bone Markings (Surface Features) 8 Bone markings Projection that are sites of muscle and ligament attachment: Tubercle (tubercle of the rib) Tuberosity (tibial tuberosity) Trochanter (femur) Epicondyle (medial epicondyle-femur) Line (line aspera-femur) Crest (pubic crest) Process (spinous process) Spine (ischial spine) 9 Bone markings Projections that help to form joints: Head (femur) Facet (costal facet) Condyle (femur) Ramus (mandible) 10 Bone markings Cavities: Sinus (maxillary) 11 Bone markings Depressions and openings for blood vessels and nerves to pass: Foramen (ovale) Meatus (acoustic meatus) Fissure (orbital) Fossa (posterior cranial fossa) 12 A typical long bone includes Diaphysis Periosteum Perforating fibers (Sharpey’s) Endosteum Epiphyses Epiphysial plate Epiphysial line 13 A typical long bone includes Articular cartilage Marrow cavity Filled with red or yellow marrow 14 Bone Structure 15 Bone Growth at an Epiphyseal Cartilage 16 Bone Histology 17 The Histology of Compact Bone 18 Compact bone Basic unit of compact bone is an osteon Osteocytes Lacunae Perforating canals (Volkmann’s) Central canal 19 Compact bone Canaliculi Lamella Circumferential Interstitial Concentric 20 The Structure of Osseous Tissue 21