Health Occupations Skeletal System – Unit 2

Spinal Column Made up of 26 bones, divided into 5 parts Function –Protect spinal cord –Provide support for head & neck Curvature gives strength & flexibility Each bone is called vertebrae Intervertebral discs –Pads of cartilage separating the vertebrae –Act as shock absorbers –Allow bending & twisting

Vertebrae Bone is called the vertebral body 5 parts –Cervical – neck, 7 –Thoracic – chest, 12 –Lumbar – waist, 5 –Sacrum – back of pelvic girdle, 1 –Coccyx – tailbone, 1

Cervical Vertebrae Thoracic Vertebrae Lumbar Vertebrae Sacrum Coccyx C1 - Atlas C2 - Axis Vertebral Body Intervertebral Disk

Thorax Ribs, Sternum, Vertebral bones –Protect heart & lungs Ribs –12 pair, called COSTAE –Attach to thoracic vertebrae on DORSAL surface of body –Types of ribs True ribs – first 7, attach directly to sternum False ribs – next 3, attach to cartilage of rib above Floating ribs – last 2, do not attach to front of body –INTERCOSTAL space – Area between ribs containing muscles, blood vessels, & nerves

Thorax (cont) Sternum –Breast bone –3 parts Manubrium – upper part, where clavicles attach Gladiolous – body, where hands are placed during CPR Xiphoid process – small piece of cartilage at bottom, DANGER during CPR –Ribs attach to sternum with costal cartilage & provide a cage protecting the heart & lungs

True Ribs False Ribs Floating Ribs Sternum - Gladiolus Xiphoid process Vertebral column

Pectoral Girdle Shoulder – made up of clavicles & scapulas Clavicle – –2 bones –Collar bones –Attach to manubrium of sternum with ligaments Scapula –2 shoulder blades –Provide for attachment of upper arm bones

Bones of the Arm Humerus – upper arm Radius – lower arm, thumb side Ulna – larger bone of lower arm, little finger side –Olecranon process – projection on upper end of ulna, forms elbow Carpals – 8 bones of wrist Metacarpals – 5 bones in palm of hand Phlanges – 14 bones of fingers

Pelvic girdle Made up of 2 os coxae (coxal or hip bones) Joins with sacrum on dorsal side of body at the SACROILIAC joint Join together on ventral side of body at the SYMPHYSIS PUBIS 3 parts, fused together –Ilium –Ischium –Pubis Acetabula – 2 recessed areas (sockets) for leg bone attachment Obturator foramen – opening between ishium & pelvis allowing passage of nerves & blood vessels to & from legs

Coccyx Acetabulum Obturator foramen Symphysis pubis Pubis Ischium Ischial spine Ilium Sacrum Sacroiliac joint

Legs Femur – thigh Patella – kneecap Tibia – lower leg, large bone, big toe side Fibula – lower leg, small bone, little toe side Tarsals – 7 bones in ankle Metatarsals – 5 bones in instep of foot Phalanges – 14 bones in toes Calcaneous – heel that is formed by the large tarsal bone

Parietal Occipital Scapula Verbebrae Olecranon process Ilium Coccyx Femur Calcaneous Maxilla Zygomatic Mandible Clavicle Sternum Ribs Xiphoid process Sacrum Pubis Ischium Symphysis pubis Patella Tibia Fibula Tarsals Metatarsals Phlanges Ulna Radius Carpals Metacarpals Phlanges Obturator foramen Humerus