THE SKELETAL SYSTEM

SKELETAL SYSTEM FUNCTIONS Every bone in your body is unique and carries its own blood supply and nerves. When bones are connected to each other they form the framework to our body. Bones support and protect our vital organs and store minerals Joints are where two bones meet and these are held together by ligaments. These give flexibility to our skeleton. Bones, joints, and muscles work together to produce movement. Minerals: Including Calcium and phosphorus.

BONES Also called osseous tissue and one of the hardest materials in the body Formed in a gradual process from birth called ossification The formation of strong bones depend on good supply of minerals such as calcium and phosphorus. Ossification: When the formation of layers of bone cells called “Osteoblasts” develop bone tissue to support the human body. Sources of calcium and phosphorus: Dairy products, green leafy veggies and meats such as beef, pork or fish.

BONE STRUCTURE 4 types of bone = *long, short, flat and irregular Diaphysis- the shaft of a long bone (the middle) Epiphysis- the ends of the bone (proximal and distal) Long bone: Femur or Tibia Short Bone: Phalanges Flat bones: Skull bones: Parietal, temporal, occipital and Frontal. Irregular bones: sacrum and mandible Sesamoid Bones: Patella

THE STRUCTURE OF BONE Bone is a form of connective tissue. It is very hard; however it is able to change and heal itself. Tissues of a bone Periosteum- forms the outermost covering of the bone Compact bone – hard, dense, strong bone that forms the outer layer of our bones Spongy bone- commonly found in the ends and inner portions of bones. Red bone marrow is found here. Medullary Cavity- open canal in the middle of diaphysis

CARTILAGE Cartilage- a smooth and white rubbery tissue that acts as a shock absorber between bones. Cartilage is more elastic than bone. Articular Cartilage- covers the surfaces of bones that form joints in order to make smooth joint movement possible and to protect the bones from rubbing against each other But more stiff than muscle. Middle ground. Loss of Articular Cartilage: Osteoarthritis. Causes pain and swelling to limit ROM and function of that joint.

Bone PROJECTIONS AND DEPRESSIONS Head: end Tuberosity: round prominence on a bone for muscle or ligament attachment Neck: center Condyle: a round circle for bones Process: extra bone tissue Epicondyle: the round ball-like structure that can sit in the condyle Foramen: opening or hole within a bone Trochanter: large prominence of a bone Tubercle: small round bump on a bone Condyle: Like a round circle for bones can be smoothly placed to form a joint. Epicondyle: The round ball-like aspect of a bone that sits comfortably in the condyle of another bone. Trochanter: A typically large prominence at the end of a bone. Tubercle: a small round bump on a bone Tuberosity: Another type of round prominence of a bone specifically for muscle and ligament attachments. Process: Extra bone tissue that has grown from a larger bone. Foramen: Refers to an opening or a hole within a bone.

The Skeleton = 206 BONES

BONES OF THE SKULL Four bones make up your skull: Frontal- front Parietal –top Temporal- sides Occipital – back Zygomatic – cheekbone Nasal- nose bone Mandible- jaw bone Maxilla – below nose, above lip

THORACIC CAVITY, RIBS, AND STERNUM The thoracic cavity protects the heart and lungs. Made up of ribs, sternum, and thoracic vertebrae. Costals (ribs)- 12 pairs First 7 = true ribs. They are attached directly to the sternum. Next 3 = false ribs. They are attached to cartilage that joins with the sternum Last 2 = floating ribs. They are not attached. Sternum (breastbone) Manubrium- upper portion of sternum Body- middle portion of sternum Xiphoid process- lower portion of sternum

SHOULDERS Clavicle (Collar Bone)- connects the sternum to the scapula Scapula – Shoulder Blade Acromion- an extension of the scapula that forms the high point of your shoulder

ARMS Humerus- upper arm bone Radius- 1 of 2 bones in the forearm. It runs up the thumb side of your forearm. Ulna- The other bone in your forearm. Olecranon Process- large projection on the upper end of the ulna that forms the point of your elbow.

WRIST AND HANDS Carpals- bones of the wrist Metacarpals- bones that form the palm of the hand Phalanges- bones of the fingers Each finger has 3 phalanges; distal, medial, proximal Thumb has 2 phalanges; distal and proximal

VERTEBRAL COLUMN 33 VERTEBRAE Functions are to support the head and body and to protect the spinal cord Types of Vertebrae First 7 = Cervical Vertebrae. These vertebrae form the neck. C1-C7 Next 12 = Thoracic Vertebrae. Form the outward curve of the spine. T1-T12 Next 5 = Lumbar Vertebrae. Form the inward curve of the spine. Largest and strongest of the vertebrae. L1-L5 Sacrum- 5 bones fused together after birth. Triangular shaped bone near the base of the spine Coccyx (tailbone)- 4 bones fused together. Forms the end of the spine.

PELVIC GIRDLE Protects internal organs and supports the lower extremities. It is made up of 3 bones fused together. Ilium- is the upper, blade shaped part of the hip. Ischium- lower part of the pelvic girdle; posterior Pubis- anterior portion of the pelvic girdle

UPPER LEG Femur- upper leg bone. Largest bone in the body. Head of Femur, Femoral Neck, Trochanters

KNEE Patella- knee cap Popliteal- posterior surface of the knee. Cruciate Ligaments- make movement possible in knee; Shaped like a cross. Anterior Cruciate Ligament (ACL) Posterior Cruciate Ligament (PCL)

LOWER LEG Tibia- “shin bone”; Larger of the 2 bones in lower leg. 90% weight-bearing Fibula- smaller of the 2 bones in lower leg.

ANKLES AND FEET Tarsals- bones that make up the ankle Malleolus (malleoli)- rounded bony protuberance on each side of your ankle Calcaneus- heel bone Metatarsals- bones of the foot Phalanges- bones in your toes (same as fingers)

STRUCTURES OF SYNOVIAL JOINTS Ligaments- connects one bone to another bone Tendons- connects muscles to bones Synovial Membrane and Fluid- surrounds and acts as a lubricant to make smooth movements possible Bursa- a fluid filled sac that acts as a cushion to ease movements in areas that are subject to friction such as shoulder, knee, and elbow joints.

JOINTS Joints are connections between bones. Types of Joints: Sutures- a jagged line where bones join together to form a joint that doesn’t move. Symphysis or cartilaginous joint- two bones are joined together and are held firmly together so they function as one bone Synovial Joints- The movable joints of the body. Ball and Socket- allow a wide range of movement in many directions. Examples are: hips and shoulders Hinge- allow movement primarily in one direction or plane. Examples are: knees and elbows

SUTURE SYMPHYSIS BALL AND SOCKET HINGE

Define the following: Crepitation Exostosis Ewings sarcoma Osteomalacia Osteoporosis Rickets Bunion Dislocation Osteoarthritis Subluxation Kyphosis Lordosis Scoliosis