The Musculoskeletal system
•206 bones •grouped into the axial and appendicular skeletons •650 muscles –approximately 40% of your body weight –also divided into an axial and an appendicular division •
Classification of Bones
•6 types - based on anatomical classification –Long bones = greater length than width –Short bones = cube-shaped, spongy bone except at surface –Flat bones = two parallel plates of compact bone sandwiching spongy bone layer
–Irregular bones = cannot be grouped –Sesamoid bones = develop in tendons where there is considerable friction, tension and stress –Sutural bones = located within joints between cranial bones
Bony Processes
• •Depressions and openings –Fissure – narrow slit –Foramen – hole for nerves, blood vessels –Fossa – cuplike depression –Sulcus – furrow on a bone surface, contains a nerve or blood vessel –Meatus – tubelike opening •Processes – projection or outgrowth on bone for attachment –Condyle – smoothened process at end of bone, forms a joint –Facet – smooth flat surface, forms a joint –Head – rounded condyle on a neck, forms a joint –Crest – prominent ridge or projection, for attachment of connective tissues –Epicondyle – projection above a condyle, for attachment of connective tissues –Line – long, narrow ridge (less prominent than a crest), for attachment of connective tissues –Spinous process – sharp, slender projection, for attachment of connective tissues –Trochanter – process of the femur, for attachment of connective tissues –Tubercle – process of the humerus, for attachment of connective tissues –Tuberosity – roughening on a bone surface, for attachment of connective tissues –