Module 1.3 Skeletal System.ppt

Skeletal System OT 505 Skeletal System Rigid framework of the human body Protects vital organs- brain, Spinal cord, heart Made up of 206 bones SKELETON Two main Categories - Axial skeleton: upright part of the body - 80 bones - Head, Thorax, Trunk...

Skeletal System OT 505 Skeletal System Rigid framework of the human body Protects vital organs- brain, Spinal cord, heart Made up of 206 bones SKELETON Two main Categories - Axial skeleton: upright part of the body - 80 bones - Head, Thorax, Trunk - Appendicular skeleton: attaches to axial skeleton - 126 bones - upper & lower extremities STRUCTURE OF BONE Bone is considered an organ Made of different types of tissue ◦ Fibrous ◦ Cartilaginous ◦ Osseous ◦ Nervous ◦ Vascular STRUCTURE OF BONE ◦ Bone considered a connective tissue ◦ Hardest type of connective tissue in the body ◦ Compact/cortical Bone: hard dense outer shell ◦ Cancellous Bone: porous/spongy inside portion called trabeculae STRUCTURE OF BONE ◦Cortical bone ◦ outside, stronger surface ◦Cancellous bone (trabeculae) ◦ spongy inner part of bone that contains nutrients Bone Anatomy STRUCTURE OF BONE (Long Bone) Epiphysis ◦ wider ends of the bone ◦ osseous in adult ◦ Cartilaginous in children Diaphysis ◦ main shaft of bone, mostly compact bone ◦ gives it strength ◦ Center is hollow < weight ◦ Contains marrow Structure of Bone Metaphysis flared point each end - Supports the epiphysis Periosteum – fibrous membrane Periosteum ◦Thin fibrous membrane covering all of the bone except the articular surfaces ◦ Contain nerve & blood vessels that provide nourishment ◦Promotes growth in diameter of immature bone & repair of bone ◦Attachment point for tendons & ligaments Growth Plates 2 types epiphysis in children who are still growing Pressure Epiphysis Traction Epiphysis located at ends of long located where bones where they tendons attach to receive pressure from bones and subject the opposing bone to a pulling traction making the joint force 2 Epiphysea l Plates Types of Bones a) Long b) Short c) Flat d) Irregular e) Sesamoid Long Bones ◦Length is greater than width ◦Largest bones in body ◦Make up most of appendicular skeleton ◦ Example: ◦ Femur Short Bones ◦Equal height, length, width ◦Cubical shape ◦Unlike long bones, short bones usually articulate with more than 1 bone ◦Found only in appendicular skeleton ◦Example: ◦ Wrist (carpal bones) ◦ Ankle (tarsals) Flat Bones oBroad, thin surface o2 layers compact bone with cancellous bone and marrow in between oMain site for manufacturing blood cells oExamples: ◦ Scapula ◦ Ilium ◦ sternum ◦ ribs Irregular Bones Mixed shapes Found only in the axial skeleton Examples: ◦ vertebra ◦ sacrum  Sesamoid Bones - Resemble shape sesame seeds - Small bones located where tendons cross the ends of long bones in the extremities - Change the angle of tendon’s attachment to increase mechanical advantage Examples: Thumb (FPB) Patella encased in quadriceps Types of Bones: APPENDICULAR SKELETON AXIAL SKELETON Long Bones Flat Bones Short Bones Irregular Bones Flat Bones No irregular bones No long bones, short bones Bone Markings When looking at bones you will see holes, depressions, ridges, bumps, grooves all serve a purpose The markings on bones serve as sites of attachment for muscles and/or ligaments. Openings in bones serve as passageways for blood vessels and/or nerves. Projections on bones take part in forming joints.  Bone Markings- Depressions and Openings  Foramen - hole through which blood vessels flow  Fossa - hollow or depression  Groove – narrow channel containing a tendon  Meatus- canal or tube-like opening  Sinus-air filled cavity within a bone  Bone Markings- Projections or Processes Fit and form joints Attach tendons, ligaments & other connective tissue  Bone Markings Condyle - rounded projection Tubercle - small rounded Eminence. prominence on bone projection Facet- flat/shallow articular surface Tuberosity - large rounded Head- rounded articular projection projection beyond a narrow Trochanter- very large neck line portion of bone prominence for muscle Crest - sharp ridge or border attachment Epicondyle - prominence above or on Spine-long,thin projection a condyle  Common Skeletal Pathologies Fractures ◦ Complete, incomplete, compound simple Osteoporosis-loss of normal bone density Osteomyelitis-infection of bone Epiphyseal- Growth Plate Fractures Wolff’s Law Definition- bone grows ( adapts) and remodels in response to the forces that are placed upon it Rubin, C.T., McLeod, KJ. Functional strains and cortical bone adaptation: epigenetic assurance of skeletal integrity. J Biomech. 19901:23 Wolff’s Law Bone Adaptation Is the converse to Wolff’s law true? If loading on the bone increases bone density, does unloading the bone weaken trabeculae? Activities and Occupations Wolff’s Law Tennis Player Weightlifters Surfers Space Work- Astronauts Runners  Common Diagnosis associated with Wolff’s law Shoulder Rotator Cuff Injuries ◦spurring on the acromian Lateral Epicondylitis spurs Review What makes up the axial skeleton? What makes up the appendicular skeleton What are the 2 types of bone? Describe. What is the periosteum? What are the 5 types of bones? Example. Name and describe 5 depressions or openings Name and describe 10 bone projections or processes. Explain Wolff’s law