Intro to Bone and Soft Tissue Flashcards
What are the 3 things the musculoskeletal system is made of?
Bone, Muscle, Connective Tissue
What is the function of bone?
What is the function of skeletal muscle?
What is the function of connective tissue?
Movement, support, protection of vital organs, calcium storage, haematopoeisis
Posture, movement (propel limbs)
Structural support, protect tissues, attachment sites e.g. attach bone to bone (tendons) or muscle to bone (ligaments)
How many bones are found in the adult skeleton compared to a child’s skeleton?
What are the names of appendicular groups of bones?
What are the names of the axial groups of bones?
206 Vs 270
Pectoral girdle, upper and lower limbs, pelvic girdle
Cranium, vertebral columb, ribcage
What are the 3 planes?
What are phrases to describe movement in all these planes?
Coronal, Saggital, and Transverse
Straight line movement or rotations, within straight line movements, we can have: lateral medial (saggital), anterior posterior (coronal), superior inferior (transverse); flexion extension, adduction abduction
What are the 6 classifications of bone by shape?
What type of connective tissue connects bone to bone?
What connects muscle to bone?
Flat, Short, Long, Sesamoid, Sutured, Irregular
Ligaments
Tendons
What are the 5 main functions of the skeletal system?
What type of bone is the patella (kneecap)?
Movement, Support, Protection of vital organs, storage of Ca2+, Haemopoesis
Sesamoid bone
What is meant by the term ‘osteo-‘?
What are the 4 main types of bone cells?
‘osteo-‘ = prefix for bone
- Osteogenic cell = bone ‘stem cell’
- Osteoblast = comes from the osteogeneic cell, involved in bone forming (secretes osteoid, catalyses mineralisation of osteoid)
- Osteocyte = ‘mature’ bone cell / resting bone cells, formed when an osteoblast becomes embedded in its own secretions
- Osteoclasts = bone consuming, dissolve and resorb bone by phagocytosis, derived from bone marrow, important during bone remodelling (bone consumed from one area and reformed in another)
What is the periosteum?
Where are the 4 types of bone cells found within in the bones?
Dense layer of vascular connective tissue enveloping the bones except on the surfaces of joints
Osteogenic = deep layers of the periosteum
Osteoclast = bone surfaces and at sites of old, injured or unneeded bone
Osteoblast = growing portions of bone, including periosteum and endosteum
Osteocyte = embedded in the matrix
The 4 types of bone cells live in systems called?
What is the name given to the canal containing the nerves, blood vessels and lymphatics in bone?
Osteons - which have lamellae (meaning layers) around a central canal called the ‘Haversian canal’
Haversian canal
What is the bone matrix made up of?
40% = organic component = collagen (mainly type 1)
60% = inorganic component = Ca2+
What factors does bone growth depend on?
What type of bone is formed initially during bone growth?
What happens afterwards during bone growth?
Age (young or old), resting bone, broken bone, etc.
Initially, immature bone is formed = laid down in a ‘woven’ manner, relatively weak
The woven bone is mineralised and replaced by mature (lamellar) bone = relatively strong
What are the 2 types of mature bone?
Where do screws get put in bone for a strong fix?
Why did cancellous bone develop?
- Cortical = compact and dense = strongest = weight-bearing
- Cancellous = ‘spongey’ = honeycomb structure = not weightbearing
So outside of the bone = cortical, inside of the bone = cancellous
Screws get placed across, from one side of the cortical bone, through the cancellous, to the other side of cortical bone
Cortical = too heavy, easier to hunt for prey / run away from predators
Cancellous bone has trabeculae. What is meant by the term ‘trabeculae’?
Matrix of inorganic tissue = spongey appearance = gives bone voluming without adding too much weight
What is the structure of long bones? Fill in the labels on the diagram:
What is another name given to a growth plate?
What is the 2nd most common fracture? (occurs mainly in elderly)
Physis or epiphyseal plate
Hip bone = top of femur
What are the 2 ways bones can form? What are some examples of where that bone type is found?
How are bones formed in the uterus?
How are long bones formed?
How do children grow?
- Intramembranous Ossification - bone development from fibrous membranes e.g. flat bones of the skull, clavicle and mandible; 2. Endochondral ossification - using a cartilage precursor that afterwards forms calcified bone
Intramembranous ossification
Endochondral ossification
From growth plates
What is a growth plate?
How do bones lengthen? (e.g. at the epiphyseal plate in long bones)
A band of hyaline cartilage found in long bones that supplies more bone during growth
At the epiphyseal plate (growth plate), there are two ‘sides’, epiphyseal and diaphyseal - the epiphyseal side contains hyaline cartilage that is active and dividing to form the hyaline cartilage matrix; and the diaphyseal side is where the cartilage calcifies and dies for it to be replaced by bone (ossification)
Chondrocyte = a cell which has secreted the matrix of cartilage and become embedded in it
How do bones grow in width?
What is the periosteum?
How does the periosteum eventually convert to bone?
Deposition of bone beneath the periosteum increases bone thickness
Outside connective tissue covering of bone = periosteum
Ridges in the periosteum create grooves for the periosteal blood supply. The periosteal ridges fuse over the blood vessel to form an endosteum lined tunnel. Osteoblasts in the endosteum build new concentric lamellae inwards towards the centre of the tunnel to form a new osteon
Which molecule helps absorb Ca2+?
What happens once Ca2+ is absorbed?
What does calcitonin do?
What can cause too much Ca2+ in the blood? And too much Ca2+ can lead to?
Vitamin D
It circulates in the blood, and is eventually taken up by bone in which it rests
Lowers plasma Ca2+ by lowering osteoclast activity and increasing Ca2+ and PO43- excretion
e.g. cancer affecting osteoclast activity - symptoms include depression, renal stones, etc.
What is collagen?
What are the 3 types of collagen and why are there different types of collagen?
Building block for most connective tissue - amino acids make up 3 polypeptides, which then arrange themselves into a triple helix - they then get built into fibrils, which form collagen fibres - these collagen fibres come together to form ligaments, tendons, parts of muscles and bone
Type I, II and III because they have evolved according to the different stressors they face
What determines the type of collagen formed?
Describe where the 3 types of collagen are found by filling in the table below:
What allows for collagen to stretch? Why does collagen not follow Hooke’s law of elasticity?
The arrangement of the amino acids forming the polypeptides
Collagen fibres crimp up (compress) and then they stretch out again, so they are not visco-elastic and so do not follow Hooke’s law
Collagens can make up tendons. What are tendons?
What are tendons made up of?
What proportion of your body weight does the achilles take while walking, climbing and jumping?
Attaches skeletal muscle to bone - very strong
Collagen fibres and arranged in bundles and closely packed parallelly to provide strength. There is also some elastin
200%, 400-500%, 700-800%
What are ligaments and what are its functions?
What are ligaments made up of? And what do they contain?
Why is propioception important?
Connects bone to bone and takes up equal amounts of stress as tendons, they stabilise joints, and enable proprioception - ability for the brain to the know where the joint is in space (i.e. flexed or entended)
Have slightly less elastin than tendons, and have 90% Type I collagen, 9% Type 3 collagen and some fibroblast cells. Contain some blood vessels and nerves in the outer covering, contain proprioceptors and can transmit pain signals via Type C fibres
Required for balance
What is cartilage? Where does it exist?
What are the 3 types of cartilage and where are they found?
Has Type II collagen in it, exists mainly between bones
Elastic, Hyaline - like cling-film on the bone (shiny - allows bone to glide), Fibrocartilage - rubbery shock absorbers found in joints e.g. knee)
Which type of cell is responsible for bone resorption?
What mineral is released from bone with activity of the cell type?
Osteoclasts
Ca2+ and osteoclasts
What are the 3 types of joints?
What is the purpose of synovial fluid?
Why does the skull have fibrous joints?
- Fibrous - found in the skull = don’t move much
- Cartilaginous - found in the spine, has a bit of stiffness and a bit of movement
- Synovial - mainly long bones + sockets = they’re the ones that move (generally) = have synovium that lines the capsule which produces synovial fluid = useful for shock absorption, contains nutrients for the joint and lubrication (to reduce friction)
Doesn’t move much = prevents brain being dented / damaged
How are joints classified?
What are the different types of synovial joints?
What are the different types of cartilaginous joints?
What are the different types of fibrous joints?
Fill in the table for the last 3 qs:
According to their function / movement e.g. elbow = hinge, hip = ball and socket etc.
What are the most common types of joints?
What are the most mobile types of joints?
What is the structure of a synovial joint?
Synovial joints
Synovial joints
They have a capsule around the joint, within the capsule, the synovial lining produces fluid called the synovial fluid - the articular cartilage moves within this synovial fluid
Why are some joints more stable than others?
Which joint is unstable? And why?
How are joints made stable?
Stable joint = strong and less mobile (contains more ligaments / tighter ligaments); unstable joint = more mobile joints
Shoulder joint –> more mobility = less stability (generally) = not much glenoid fossa covering the head of the humerus (unlike the hip bone, where there is more coverage)
With ligaments, tendons and cartilage
Why is the hip more stable than the shoulder joint? Fill in the table:
Why are gymnasts and dancers more prone to ligamentous injury?
Often have more elastin in their structure - more rotation, hypermobility (=excessive ligament laxity and overuse) and movement of the joints
