Bones (wk1) Flashcards
Function of the skeleton - Support
-It provides a framework
Function of the skeleton - Protection
-Bones protect our internal organs
Function of the skeleton - Movement
-The body can move as a whole or in individual parts/limbs
Function of the skeleton - Production of RBC
-Some bones such as the pelvis contain bone marrow, which can produce platelets, red blood cells and white blood cells
Function of the skeleton - Storage of minerals
-Bones store minerals such as calcium and iron
Function of the skeleton - Endocrine regulation
-Bones secrete hormones and thereby control various psychological pathways
The axial and appendicular skeleton
-Most people have 206 bones when they get to adulthood
-The axial skeleton is the main trunk and consists of the skull, vertebral spinal column, sternum and ribs (thoracic cage)
-The appendicular skeleton consists of the extremities of the body, predominantly the limbs e.g. shoulder girdle and arms
The axial skeleton - Skull
-The cranium consists of 22 bones; split into 8 bones at the back and 14 facial bones
-The main goal is to protect the brain
-Complete the diagram (27/09)
The axial skeleton - Vertebral column
-It is also known as the spinal column and extends from the skull to the pelvis
-It is made up of individual vertebrae, which are interconnected by a cartilaginous intervertebral disk
-Divided into 7 regions; 7 cervical, 12 thoracic, 5 lumbar, 5 (fused) sacrum and 3-5 (fused) coccyx
-When viewed laterally, there are 4 curvatures
-It protects the spinal cord
The axial skeleton - Thoracic cage
-Consists of 12 pairs of ribs, their costal cartilage and the sternum/breastbone
-Ribs 1-7 are classed as true ribs as they adjoin directly onto the sternum
-Ribs 8 -12 are considered to be false ribs as they don’t attach by their own costal cartilage onto the sternum
-Ribs 11-12 are floating ribs as they don’t attach to the sternum at all
The appendicular skeleton - Shoulder girdle and arms
-The shoulder girdle consists of the clavicle and the scapula
-The arms attach to the shoulder girdle
The appendicular skeleton - Hands
-There are 8 carpal bones in each wrist
-There are 5 metacarpal bones in each hand/wrist
-There are 5 proximal phalanges, 4 intermediate and 5 distal phalanges in each of our hands
-The distal row of the carpal bones are; capitate, trapezium, trapezoid and hamate
-The proximal row of the carpal bones are; pisiform, triquetrum, lunate and scaphoid
The appendicular skeleton - Pelvic girdle and legs
-Consists of 2 bones which then attach to the sacrum to form our pelvic ring, where the legs then attach
-There’s 3 parts to the innominate bones; ilium, ischium and pubis
The appendicular skeleton - Feet
-There are 7 tarsals in each foot
-There are 3 types of cuneiform; medial, intermediate and lateral
-5 metatarsals
-2 phalanges in the big toes, but each of the other toes have 3 (14 in each foot)
What are the different types of bones?
Long, Sesamoid, Flat, Irregular and Short
Description of a long bone
-They function to support the weight of the body and facilitate movement e.g. femur
Description of a sesamoid bone
-These are embedded in tendons e.g. found in tendons of the feet and hands
Description of a flat bone
-They can provide protection e.g. cranium
Description of an irregular bone
-Help protect specific internal organs e.g. bones of the pelvic and vertebrae
Description of a short bone
-They provide stability and some movement e.g. wrist bones
Bone composition
-Osseous tissue -> Collagen and hard minerals (make bones hard and rigid) e.g. calcium, magnesium and phosphate
-There are 2 types;
1. Cancellous or spongy bone (honeycomb structure)
2. Compact bone
Bone - Structured and mechanical properties
-Compact -> Dense and tough (provides protective layer)
-Spongy -> Light and strong (trabeculae) - found on the inside of bones and is very light
What is the structure of a long bone? (and description)
-Most common bones found in the human body
-Composed mostly of compact bone and have enlarged ends that are filled with spongy bone
-The dialysis is the shaft of the long bone and makes up the length of the bone
-The epiphysis is the two ends of the bone, which is covered in articular cartilage, which allows the bones to slide past one another. The interior is filled with spongy bone
-The medullary canal is where the yellow bone marrow is found in adults
Bone cells
-Osteoblasts -> Bone forming cells e.g. found in some immature bones
-Osteoclasts -> Break down the bone, releasing the calcium and phosphate and help to continue the remodelling of healthy bone tissue
-Osteocytes -> Mature bones found deep within mineralised bone
What is the micro-structure of bone?
-Compact bones make up about 80% of the body bone mass because its denser and is made up of a large number of parallel tube-shaped units called osteons
-The osteon gives the bone strength and in the central canal, it contains nerves, lymphatics and blood vessels which are partnered with neighbouring canals
What is osteogenesis?
-It is the development of bone tissue
-The process begins before birth and will continue into life until your 21st year
-Calcium and phosphate salts are deposited through the cartilaginous osteoid and increasingly calcify the cartilage model and convert it into a harder, more mature bone
-While the cartilage is equal to the rate of ossification, the bone will continue to lengthen
Remodelling of bones
-There is a constant turnover of bone tissue and that’s mediated by osteoblasts and osteoclast activity (bone turnover)
-On average, about 10% of bone is replaced each year, but the rate at which individual bones remodel varies
-Wolff’s Law -> Bone density changes in response to the forces placed on the bone
-A lack of exercise leads to weak and fragile bones, which reduces the rate of remodelling of bones
What is joint function?
-The amount of movement available between the articulating bones
What are the 3 types of joint functions?
Synarthroses, Amphiarthroses, Diarthroses
Joint classification/function
-Synarthroses
-Immovable -> Immobile or nearly immobile joints
-They have a strong union between the articulating bones
-They are important at locations where the bones provide protection for vital organs e.g. the joints between the bones of the skull and where they can protect the brain
Joint classification/function
-Amphiarthroses
-Slightly movable -> Joints with limited mobility
-There are small movements allowed which will add up to a much larger sum
-E.g. the joint that unites the bodies of adjacent vertebrae
Joint classification/function
-Diarthroses
-Freely movable ->Freely movable joints that are found in the appendicular skeleton, which allow limbs to have a wider ROM
-These joints can be divided into 3 types; uniaxial (movement in a plane around a single axis), biaxial (movement in two planes) and multiaxial (movement in three planes)
What are the different types of joint structure classifications?
-Cartilaginous (fibro or hyaline cartilage)
-Fibrous (dense connective tissue)
Joint classification/structure
-Fibro or Hyaline cartilage (synchondroses + symphysis)
-Synchondroses -> Bones are united by a continuous layer of hyaline cartilage which is temporary
-Symphysis -> The articulating surfaces of these bones are covered in hyaline cartilage but also have a pad of hyaline cartilage between them to allow small movements to take place
Joint classification/structure -> Dense CT
-Sutures, syndesmosis, gomphosis
-Sutures -> A form of fibrous joint that permits no movement and are only found where the bones of the skull meet one another
-Syndesmosis -> United by a larger amount of fibrous tissue, by a ligament or an interosseous membrane. The flexible membrane allows the joints to move
-Gomphosis -> A fibrous joint where a peg fits into a socket and is held in place by a fibrous band or ligament
Synovial joints description
-These are freely movable joints with movement limited by their associated joint capsules, ligaments and muscles crossing the joint
-The articular surface is covered in an articular hyaline cartilage which is hard and smooth, enabling the bones to move against one another with minimal friction
-The deep surface of the capsule is lined by the synovial membrane which secretes synovial fluid into the joint cavity
Name the 6 types of synovial joint and draw them
Gliding, Hinge, Pivot, Ellipsoid, Saddle and Ball and socket
Movement v Stability
-Stable joints allow for little or no movement between the bones, but joints that provide the most movement are the least stable
-Strongly united, stable joints allow little or no movement at all -> these joints are associated with protection e.g. for vital organs
-Joints with greater ROM are much less stable e.g. the shoulder
What are joint arthrokinematics and can you name the 3?
-The general term for specific movement of joint surfaces
-Roll, Spin, Glide
Joint arthrokinematics - Roll
-Draw the diagram
-One surface rolls over the other surface
Joint arthrokinematics - Spin
-Draw the diagram
-Spinning is like a basketball being spun on a finger
Joint arthrokinematics - Glide
-Draw the diagram
-Slide or glide is a translated movement, with one fixed point sliding over the other surface slowly
