MSK structures and function Flashcards
What are the connective tissues of the body composed of
cells embodied in a matrix which varies in its quantity and composition
What are the 3 types of cels in connective tissue
Bony - osteoid (produced by osteoblasts)
Cartilaginous - chondroid (produced by chondroblasts)
Fibrous - collagenous tissue (produced by fibroblasts)
What type of collagen does bone contain
type 1
What type of collagen does hyaline cartilage contain
type 2
What kind of collagen does skin contain
Types 1 and 3
How do connective tissues grow
by cell proliferation and deposition of intercellular material
What is the function of “ground substance”
It is an important water-binding agent
It acts as an ion-exchange resin in controlling the passage of electrolytes
What factors affect the deposition of ground substance
hormones and vitamins
What does demineralisation of bone result in and what might it be caused by
loss of bone strength
May be caused by diminished matrix formation, inadequate calcification or bone resorption
What is the shaft of a bone called
diaphysis
what is the name of the zone adjacent to the epiphyseal line
metaphysis
What part of the developing bone is the most metabolically active
Metaphysis
What do short bones consist of
cancellous core surrounded by a layer of cortical bone, partly covered by articular cartilage
Where are important sites of blood formation throughout life
vertebral bodies
Where on the bone do pathological factors occur
transversely
What gives bone hardness and strength
osteoid - it is heavily infiltrated with calcium salts
What is a normal bone composed of
concentric cylinders of matrix with cells lying in lacunae between the layers, the whole forming a “haversian system”
Describe the difference in the haversian system in the hard cortex and in the cancellous bone
Hard - tightly packed together
cancellous - more loosely arranged
What are the hollow centres of the shafts of bone filled with
marrow
What occurs in the marrow thought the bone in the child
Haemopoiesis
What is each bone ensheathed by
fibrous periosteum with an undlerying layer of osteoblasts
How do bone initially develop in the fetus
As condensations of mesenchymal tissue i the axis of the limb
What eventually ossifies
The matrix
How does growth in width occur
deposition of non-cartilaginous subperiosteal bone
When are the most common times for bone remodelling
During growth and after fracture healing
Cartilage varies in appearance and physical characteristics depending on what
predominant type of fibril and the density of the matrix
What are the two types of fibril
collagen and elastin
What are the 3 types of cartilage
Hyaline
White fibro-cartialge
Yellow or elastic fibre-cartilage
Where is white fibre-cartilage mainly found
in midline structures e.g. intervertebral discs and symphyses
Where is yellow or elastic fibre-cartilage found
nasal and aural cartilages
What type of cartilage contains the highest proportion of elastin
Yellow or elastic fibrocartilage
How does cartilage grow
direct proliferation of the cells with pericellular deposition of matrix
Why does damage to an articular surface have long-lasting consequences
The capacity of hyaline cartilage to regenerate and repair itself is strictly limited
What does fibrous tissue consist of
mainly collagen fibres with relatively little matrix
What is an example of an inherited disorder of collagen metabolism
Osteogenesis imperfecta
What does scar tissue consist of
Almost entirely collagenous material
What is a keloid
Formation of over-exuberant scar tissue
What race is more prone to developing a keloid
Those with Black skin
What are ligaments necessary for
joint stability
What is a partial rupture of a ligament known as and what is the prognosis
Sprain or strain
Usually heals completely
Give an example of a fibrous joint
Sutures of the skull
Give an example of a cartilaginous join
Vertebral bodies
Where does the articular cartilage of a synovial joint derive most of its nutrition
from the synovial fluid
What is the main function of a fibre-cartilaginous disc
Stress-distributing function
Describe the appearance of articular cartilage
smooth and elastic
What are the functions of the muscles
moving the joints
joint stability
What is skeletal muscle composed of
fibres whose length varies from a free mm to about 30cm
Each fibre contains many nuclei embedded in its synctium and the fibre itself is built up of many myofibrils each of which consist of units of the proteins actin and myosin
What happens if there are many fibres arranged obliquely to the line of pull
the power is greater but the ability to shorten is less
Where do nerves enter the muscle
at the motor point
How do muscles attach to bone
by a tendon
Why do tendons frequently become separated or protected from their underlying bones
The do not resist pressure very well
What are sesamoid bones
larger tendons which contain a bone within their substance at the place where they cross a joint and have a bear considerable stress
Give an example of an anatomical bursa that communicates with the nearby joint that may become distended or diseased if pathology develops in the underlying joint
Baker’s cyst
