Bones and Joints Flashcards
The two parts to bone
outer cortex and inner medulla
other name for the outer cortex of bone
cortical bone
contained within the inner medulla of bone
bone marrow - slowly changes to yellow fatty bone
particular bones for making red and white blood cells
hip, breast bone, skull, ribs, vertebrae and in cancellous spongy material at proximal ends of long bones
what is the periosteum
the fibrous connective tissue surrounding the bone
What is the periosteum important for?
bone remodelling and repair; access to lymph vessels; innervation and vascularisation of bone
Where does periosteum not exist?
where muscles and tendons attach the bone
How do arteries and veins supply the bone?
through nutrient vessels
Where does the epiphysis receive nutrients from?
vessels around the joints but not the nutrient vessels
what is endochondral ossification?
the process by which small inital hyaline cartilage grows and turns to bone - particularly long bones
what is the primary ossification centre?
where capillaries start to enter the shaft and drive the ossification process - embyronic cells condense and start to be replaced by cartilage cells to take the template of the long bone - then the capillaries form
Where is the secondary ossification centre?
in the epiphysis
What is the first and last bone to start ossification?
the clavicle
Give an example of a flat bone
neurocranium or sternum
Give an example of a long bone
humerus
femur
phalanges
Give an example of an irregular bone
Vertebrae
?Scapula
Bones of the face
Give an example of a sesamoid bone
patella
What is a sesamoid bone?
a bone that has tendons and helps to prevent friction at a joint
Give an example of a short bone
Carpals
Tarsals
What increases the incidence of fracture at the neck of the femur?
there is less compact bone at the joint
the bone is thin and angled at the joint
Why are fractures common in the clavicle?
there is less muscle and tendon support in the mid-lateral third of the clavicle - broken when fallen onto outstretched hand
What substance is deposited around the fracture to start the formation of new bone?
collagen
When do body features develop?
during development around other structures i.e. the foramen develops around the arteries and spinal cord in the skull
How can the skeleton be split?
into appendicular and axial
What does the axial skeleton include?
the skull, the vertebrae, the hyoid bone, chest
What does the appendicular skeleton include?
long bones of upper and lower limbs, pelvic and pectoral girdles
how is the skull divided?
neurocranium and viscerocranium
What bones comprise the cranial vault?
frontal, parietal, temporal, occipital, sphenoid
What bones comprise the facial skeleton?
nasal, mandible, maxilla, zygomatic bones
Describe Le Fort I
the maxilla and palette are broken
Describe Le Fort II
the fracture is pyramidal in shape; maxilla, zygoma and nasal bones
Describe Le Fort III
cranial-facial dislocation where the fracture is through the facial skeleton
What are the numbers of the vertebral types?
cervical - 7 thoracic - 12 lumbar - 5 sacral - 5 fused coccygeal - 4 fused
What is special about the C1 atlas?
no body or spinous process - posterior and anterior arches
What is special about the C2 axis?
has odontoid process which allows the atlas to rotate
What is the special about the C7 vertebrae prominens?
it is the first palpable spinous process 70% of people
What are the three forms of ribs?
true - 1-7
false - 8-10
floating ribs - 11&12
Why is the first rib less likely to fracture?
protected by the clavicle
What is bone?
bone is a hard connective tissue that lives, dies and can be remodelled following injury
What are the functions of bone?
support and protection of organs
calcium metabolism
RBC formation in red bone marrow
Attachment for muscles
What is cartilage?
a less hard connective tissue than bone that is located where mobility is required at articulations
What are the different joint classifications?
fibrous
cartilaginous
synovial
What are fibrous joints?
joints with fairly limited mobility and thus quite stable
What are the types of fibrous joints?
syndesmoses
sutures
What are syndesmoses?
unite bones with fibrous sheet membrane which is partially moveable
What is an example of syndesmoses?
interosseus membrane i.e. between radius and ulna or tibia and fibula
What are sutures?
the most stable joints between the bones of the skull
What is an example of a suture joint?
coronal and sagittal sutures
What are the sutures like in the neonatal skull?
they are wide fibrous sutures that are known as fontanelles - start to close at 9-18months
What are the features of cartilaginous joints?
fairly limited mobility and relatively stable
What are the types of cartilaginous joints?
primary cartilaginous
secondary cartilaginous
what are the features of the primary cartilaginous?
synchondroses found at bones joined by hyaline cartilage such as the epiphyseal growth plate in the long bones
What are the features of the secondary cartilaginous?
symphyses are strong and slightly moveable fibrocartilage found in places such as the intervertebral discs
what are the parts of the intervertebral discs?
outer fibrous annulus fibrosus
inner soft nucleus pulposus
What are synovial joints?
the most common and moveable joints which occur at limbs which have high levels of movement i.e. elbow, hip shoulders
what covers the articular surface of synovial joints?
hyaline cartilage
what is a feature of hyaline cartilage?
very spongy and smooth and avascular
What is the issue with hyaline cartilage being avascular?
when broken it does not grow back very well
What function does the synovial fluid do?
cushions, nourishes and lubricates the joint
What improves synovial joint stability?
ligaments
What are bursae?
associations with synovial joints that prevent friction around the joint and separate from the joint cavity
What are the 5 subtypes of synovial joint?
pivot - neck for shaking head
ball and socket - hip
plane - minimal movement in one plane - acromioclavicular
hinge - elbow
biaxial - reasonable movement in one plane, less in the other
What are the subtypes of biaxial joints?
condyloid and saddle
What is subluxation?
where the joint is displaced causes a reduced area of contact between the articular surfaces
What is a dislocation
a complete loss of contact between articular surfaces
Where are common dislocations?
TMJ, shoulder, hip, knee, pubic symphysis, ankle, interpharyngeal
What is involved in the temperomandibular joint?
the mandibular fossa and the articular tubercle of the temporal bone superior and the head of the condylar process of the mandible inferiorly
what are periarticular arterial anastomoses?
arteries found around the joint to provide an alternative blood supply when the main supply is blocked or damaged. They involve connections between arteries around the joint
