MSK system bones and joints Flashcards
Four components of the
musculoskeletal system?
- Connective tissue
◦ Fat
◦ Fibrous tissue - Skeletal tissue
◦ Cartilage
◦ Bone - Muscular tissue
◦ Skeletal muscles - Joints
Name the connective tissues and their roles
Fat:
◦ Insulates, “packs”, absorbs shock (e.g.
heel)
Fibrous tissue:
- Ligaments: pass from bone to bone,
around joints
- Tendons: attach muscle to bone
- Protective membranes e.g. around muscles and bones
what are the 2 types of cartilage
Hyaline cartilage (or articular cartilage)
Fibrocartilage
what does Hyaline cartilage (or articular cartilage) do?
covers the articular surfaces of bones to prevent friction
what does Fibrocartilage do?
present among collagen fibres to
strengthen and support framework:
- intervertebral discs
- menisci
what are some functions of bones?
- provide the body’s framework
- provides attachment to muscles and tendons
-allows movement of whole body/body parts
- forms boundaries of cavities e.g., cranial, thoracic
- protects delicate organs
- production of blood cells in red bone marrow
- mineral reservoir
what are the 4 classes of bone?
- Long
- Short
- Flat: thin and flat
- Irregular
What do Long bones allow for?
name some.
- Movement
- the humerus, radius, ulna, femur, tibia, fibula, phalanges
Short bones are strong and compact.
how much movement do they allow for? name some short bones.
- some movement
- carpals, tarsals
What do Flat bones allow for?
name some.
- muscle attachments and / or protection
- cranial cavity, ribs, sternum
name some Irregular bones
- some skull bones, vertebrae, pelvis
Describe the structure of a Long bone
Diaphysis - shaft
- compact bone
surrounds the:
- medullar cavity (fat storage)
lined by:
- endosteum
Epiphyses (proximal & distal) ends
- outer surface (compact bone)
- central regions (spongy bone)
- Periosteum covering
what is the Periosteum?
tough layer that covers all bones (but not the joints)
- contains cells that can make bone
- important to increasing bone thickness
- important in bone repair
- continuous with ligaments and tendons
(bone cells) what are Osteoblasts?
Osteoblasts: bone forming cells
(bone cells) what are Osteocytes?
Osteocytes: mature bone cells which monitor and maintain bone tissue
(bone cells) what are Osteoclasts?
Osteoclasts: bone dissolving cells - to remove bone tissue
what is the working relationship between Osteoblasts and Osteoclasts?
what do they keep relatively constant?
Osteoblasts (deposit) and osteoclasts (reabsorb) work
continuously throughout life thus the overall bone mass
should remain relatively constant
what types of things does bone activity depend on?
- hormones
- blood calcium levels
- patterns of activity
- balance of activity of bone cells
where and when do bones begin to form?
Firstly:
in a primary ossification centre: at weeks 7-12 of gestation
After birth:
in secondary ossification centres appearing in Long Bones
(bone growth) what happens in the Epiphyseal region within bone?
the Epiphyseal is a region of cartilage where the diaphysis continues to grow
when bone growth completed, epiphyseal cartilage is replaced by bone, uniting the epiphyses with the rest of the bone
What do joints enable?
Movement
3 main types of joint?
Fibrous
Cartilaginous
Synovial
what are the main characteristics of fibrous joints?
- the tissue is made up of collagen fibres which run between the bones
- there is no joint cavity
- the degree of movement is limited
what are the three SUBTYPES of FIBROUS joints?
- Suture: only occurs in skull
- Syndesmosis: cord or sheet of dense fibrous connective tissue.
The tibia/fibula and radius/ulna joints connecting these are syndesmosis - Gomphosis: peg-in-socket fibrous joint. (the articulations of teeth)
what are some characteristics of Cartilaginous joints?
- very strong, flexible and elastic
- no joint cavity
- limited or no movement
example: articulation of 1st rib to sternum, intervertebral discs
what are some characteristics of Synovial joints?
- the presence of a cavity between the bones; the joint or synovial cavity
- all are freely moveable
- account for the majority of articulations between bones
What are Strength, Stability and ROM determined by?
- the shape of the articular surfaces of the bones
- the ligaments: strong bands of dense fibrous connective tissue which bind the adjacent bones together
- muscles which extend between the two bones comprising the joint
Types of synovial joints
Plane: surfaces are flat or slightly curved and can glide over one another (inter carpal joints)
Hinge: convex portion of one bone fits onto the concave portion of another (elbow/knee)
Pivot: rounded part of one bone fits into a groove of the other to allow rotation (radio ulnar joint, atlas and axis)
Ellipsoidal / Condyloid: oval surface of one bone fits onto a concave area of another
◦ Radio carpal, MCP joints
Saddle: similar to condyloid but greater
movement enabled
◦ base of thumb
Ball and socket: all movements enabled
◦ Hip
◦ Shoulder
