*Anatomy - Bones and joints Flashcards
What are 6 purposes of bones?
Support Protection Calcium metabolism RBC formation Mechanical basis for movement and attachment site for skeletal muscles Salt storage
Where is cartilage located?
Where more flexibility and motility is require (joints)
How does cartilage obtain oxygen and nutrients?
Via diffusion (avascular)
5 shapes of bones?
Long bones Short bones Flat bones Irregular bones Sesamoid bones
Example of a long bone?
Tubular e.g. humerus
Example of a short bone?
Cuboidal e.g. in tarsus and carpus
Example of flat bone?
Flat bones of cranium (usually have a protective function)
Example of an irregular bone?
Have various shapes other than long, short or flat e.g. bones of the face
Example of sesamoid bone
Patella (develop in certain tendons ad are found where tendons cross the ends of long bones in the limbs - protect tendons and often change angle of tendons was they pass to there attachments)
Look at joint diagram
…
What does costo and control mean related to?
Costo = ribs Condral = cartilage
3 subtypes of joints?
Fibrous
cartilagenous
synovial
(each is a compromise between mobility and stability e.g. increased mobility = decreased stability)
Types of fibrous joints?
Syndesmoses
Sutures
What does syndesmoses do?
Unites joints with fibrous sheet (either a ligament or a fibrous membrane)
Examples of a syndesmoses?
Interosseous membrane
Mobility of syndesmoses?
Partially movable
Where are sutures found? Example?
between bones of the skull
Coronal suture
(almost completely obliterate away in adults)
Mobility of sutures?
Highly stable
What are the names of the wide sutures in the neonatal skull due to incomplete ossification of the cranial bones and the resulting incomplete closure of the sutures - stay open until the baby s approximately 18 months?
Fontanelles
Name of the 3 fontanelles?
Anterior
Posterior
Lateral
What are cartilaginous joints connected entirely by?
Cartilage (either hyaline cartilage or fibrocartilage)
Mobility of cartilaginous joints?
Allow more movement than fibrous joints but less movement than synovial joints
2 types of cartilaginous joints?
Primary cartilaginous (synchondroses) Secondary cartilaginous (symphyses)
What type of cartilage joins synchondroses?
Hyaline cartilage
What are the purpose of synchondroses?
permit slight bending during early life and permit growth in the length of a bone by creating temporary unions such as those present during the development of a long bone where the body epiphysis and the shaft are joined by an epiphysial plate -> when full growth has been achieved, the epiphyseal plate converts to bone and epiphysis fuses with the diaphysis
How does the strength and stability of secondary compare to primary cartilaginous joints?
secondary = more stable and strong (still has a small amount of flexibility)
What type of cartilage makes up secondary cartilaginous joints?
Fibrocartilage
Example of a symphysis?
Intervertebral disc
Structure of the intervertebral disc?
Outer fibrous annulus fibrosus (fibrous ring of fibrocartilage)
Inner soft nucleus pulposus
What type of cartilage covers synovial joints?
Hyaline “articular” cartilage
What wraps around synovial joints? What is this?
A capsule (superficial strong fibrous layer with a deep synovial membrane layer secreting synovial fluid)
What are the 3 purposes of synovial fluid?
To nourish, lubricate and cushion the joint)
Fibrous bands from bone to bone?
Ligaments
Fibrous bands from muscle to bone?
Tendons (insert onto bones at either sides of the joint)
What are bursae?
Extensions of joint cavity or closed sacs separate from the joint
5 subtypes of synovial joints?
Plane Hinge Biaxial Ball and socket Pivot
Movement of plane joints?
Minimal movement in one plane e.g. acromioclavicular joint
Movement of hinge joints?
Reasonable range of movement in one plane e.g. elbow joint
Biaxial joint? + subtypes
Reasonable range pf movement in one plane and less in another. Can be either saddle e.g. carpometacarpal or condyloid e.. metacarpophalangeal joint
Ball and socket joint?
Good range of multi-axial movement e.g. hip joint
Pivot joint?
one part of bone rotates around the other e.g. shaking head (atlanto-axial joint)
What is the most mobile and therefore least stable joint in adults?
Synovial (followed by cartilaginous and then fibrous) - synovial joints are therefore most likely to dislocate
What is more commonly dislocated, the shoulder or the hip?
Shoulder