Bones And Fractures Flashcards
What do bones of the skeleton provide?
Structural function
Mobility
Support
Protection for the body
Storehouse for essential minerals
What is the epiphysis always covered in?
Cartilage
What is the metaphysis of a long bone?
Widened ares between the epiphysis and diaphysis
What is the main artery of a long bone?
Nutrient artery
What is the medullary cavity of a long bone?
The hole in the middle
How many layers does the periosteum of a long bone have and what do they do?
2 layers
Outer is where the tendons and ligaments attach to
Inner has osteoprogenitor cells
What are the 2 types of osseous tissue?
Compact and spongy
What is spongy bone like?
Honeycomb network
What is compact bone like?
Solid hard layer
Where is compact bone found?
External layer of all bones
Where is spongy bone found?
In inner parts of the axial skeleton and epiphysis of long bones
How is compact bone arranged?
Tissue is arranged in osteons, units of lamellae are laid down in adjoining series of concentric rings
How are the lamellae arranged in spongy bone?
In branching columns called trabecular
Spaces between trabecular are filled with either red or yellow bone marrow
Trabeculae are orientated along lines of stress
Where are osteogenic cells found?
In the endosteum of bone and inner layer of periosteum
Which cells develops into an osteoblast?
Osteogenic cells
Which cells form bone tissue?
Osteoblasts
Which cells maintain bone tissue?
osteocyte
What do osteoblasts do?
Build matrix and collagen fibres but cant divide
Which cells clear bone cells?
Osteoclasts
What do osteoclasts come from?
Monocytes
Which bone cells are undifferentiated?
Osteogenic/osteoprogenitor cells
Where are osteocytes found?
They sit in the lacunae of compact and spongy bones
Where are osteoblasts found?
On the surface of the bone
Where are osteoprogenitor cells found?
In the endosteum and inner layers of periosteum
Where are osteoclasts found?
On the surface of bones
Which bone cell is mature bone cell that maintains the bone matrix?
Osteocyte
Which bone cell is an immature bone cell that secretes organic components of matrix?
Osteoblast
Which bone cell is a stem cell whose divisions produce osteoblasts?
Osteoprogenitor cell
Which bone cell is a multinucleate cell that secretes acids and enzymes to dissolve bone matrix ?
Osteoclast
What is remodelling in bones?
It is the removal and replacement at the same site
What is growth in length of a bone related to?
Cartilage
What is growth in width due to?
Osteoblasts making more bone
What is widthway growth of a bone called?
Apposition all growth
What do the Periosteal arteries supply blood to?
Osteons and the outer part of compact bone
Where do Periosteal arteries penetrate bone?
Penetrate the periosteum through Volkmann’s canals
Where do the nutrient arteries enter the bone?
Enter through diaphysis through nutrient foramen
What do nutrient arteries supply?
Medullary cavity of the inner part of compact bone
What do metaphyseal arteries supply?
Spongy bones and marrow in this area
Where do metaphyseal arteries enter the bone?
At metaphysics
What do epiphyseal arteries supply?
Spongy bone and marrow in this area
Where do epiphyseal arteries enter the bone?
Enter at the epiphysis
Name 5 factors that remodelling is affected by?
Age
Mechanical stress
genetics and environment
Calcium and phosphate levels
Hormones
Name 4 bone disorders caused by disorders of development
Agenesis
Osteogenesis imperfecta
Spina bifida
Achondroplasia
Name 4 endocrine disorders that can cause bone disorders
Gigantism
Acromegaly
Pituitary dwarfism
Hyper/hypoparathyroidism
Postmenopausal osteoporosis
Name 3 nutritional problems that can cause bone disorders
Rickets
Osteomalacia
Scurvy
After what age do you slowly begin to lose bone mass?
After mid-30s
What is an open/compound fracture?
It is when bone has managed to break through skin -> there is soft tissue involvement
What is an impacted fracture?
It is when one fragment is driven into another with such force that 2 bone breaks are forces into each other
What is a comminuted fracture?
It is when it is broken into lots of different pieces
What is a closed/ simple fracture?
It is when skins not broken and soft tissue involvement is less
What is a displaced fracture?
It normally has more than 2 fragments and the fragments have moved from original position due to muscle spasm
What is a spiral fracture?
A fracture caused by twisting forces
What is an oblique fracture?
A combination of twisting and direct force
What is a green stick fracture?
A fracture only seen in children
They have more collagen and bones are softer so bone bends with a couple of splinters
What is a depressed fracture?
A skull fracture
What is a transverse fracture?
A fracture straight across the bone
What is a Colle’s fracture?
A fracture at the distal end of radius
What is a Pott’s fracture?
A fracture at one or both ends of malleoli
What are the 4 stages of healing of fractures?
Hepatoma formation
Fibrocartilaginous callus formation
Bony callus formation
Bone remodelling
When does hepatoma formation occur in healing of fractures?
Occurs immediately and continues for 48-72 hours
What happens in the fibrocartilaginous callus formation stage of healing of fractures?
Fibroblasts invade the procallus and lay down collagen
Chondroblasts produce fibrocartilage
What happens in the hematoma formation of healing of fractures?
Clot produced in 6-8 hours, bone cells die
Inflammation brings in phagocytise cells
New capillaries grow into damaged area
What happens in the bony callus formation of fracture healing?
Osteoblasts secrete spongy bone that joins the broken ends of bone lasts 3-4 months
What happens in the bone remodelling stage of fracture healing?
Compact bone replaces the spongy in the bony callus
Surface is remodelled back to normal shape
Sometimes a palpable lump remains
How long does the union of a spiral fracture of the upper limb take?
3/52
What is the union of a fracture?
The fibrocartilaginous formation
What is the consolidation of a fracture?
Bones callus formation
How long does the consolidation of a spiral upper limb fracture take?
6/52
How long does the union of a transverse upper limb fracture take?
6/52
How long does the consolidation of a transverse upper limb fracture take?
12/52
How long does the union of a spiral lower limb fracture take?
6/52
How long does the consolidation of a spiral lower limb take?
12/52
How long does the union of a transverse lower limb fracture take?
12/52
How long does the consolidation of a transverse lower limb take?
24/52
Name 8 factors affecting the rate of fracture healing
Type of fracture
Site of fracture
Vascular supply
Age of patient
Movement at fracture
Separation of bone ends
Infection
Bone pathology
What are the clinical features of a fracture?
Pain and tenderness
Swelling and bruising
Deformity and angulation
Impaired function
Shock
What test is done for a fracture?
X ray -> AP and lateral
Name some complications of fractures
Delayed/mail/non0union
A vascular necrosis
Sudeck’s atrophy
Compartment syndrome
Volkmann’s ischaemia
Myositis Ossificans
Blood vessel, nerve or visceral damage
Tendon injury
Fat embolus
Osteoarthritis
Growth impairment
What is a pathological fracture?
A broken bone that’s caused by a disease rather than an injury
What is a boxers’ fracture?
When you break a bone at the base of your finger, near the knuckle or neck of the bone, caused by hitting a hard object with a closed fist
