MS System: Joints and Muscles Flashcards
how many joints are in the body?
230
how many joints are in each hand and foot?
27
what are the 3 types of joint?
fibrous, cartilaginous, synovial
what is the difference between the 3 kinds of joint?
the nature of the material between the bones
how much movement in fibrous joints?
none
what are 2 examples of fibrous joints?
suture joints of the skull and teeth
the development of the skull…
in 8 parts until after birth where they fuse after 24 months into interconnecting plates of skull with rigidity and strength
what are the 2 names given to the joint that is very strong and does not move?
synchondrosis joint or primary cartilaginous joint
examples of synchondrosis joint? (2)
costal cartilages and ribs, epiphyseal plates in growing bones
what are the 2 names that are given the joints that allow limited movement?
symphyses or secondary cartilaginous joints
examples of symphyses joints? (3)
joints of sternum, intervertebral discs, pubic symphysis
where are symphyses joints found?
midline of axial skeleton
what is the name given to joints that allow free movement?
synovial joints
what is the fibrous capsule composed of?
collagen fibres
where might the collagen fibres of the fibrous capsule be thickened?
along lines of stress
how are ligaments formed?
through the thickening of the collagen fibres of the fibrous capsule
what do ligaments do?
restrict movement that protects the joint from damage eg sprained ankle
where is an intrinsic ligament found?
as part of the capsule
where is extrinsic ligament found?
outside the capsule eg knee with ligament that holds the patella in place
what is articular cartilage?
hyaline cartilage that creates frictionless surfaces and has a poor blood supply
what is synovial membrane?
collagenous tissue that lines the fibrous capsule and secretes synovial fluid
what does synovial fluid consist of? (3)
hyaluronic acid, lubricin, a small number of phagocytic cells
what does synovial fluid do? (3)
reduces friction between articular surfaces, provides nutrients and oxygen for articular cartilage and removes waste
how does the alignment of glycoprotein molecules change in synovial fluid?
with exercise, exercise decrease viscosity so lubrication improves (thixotropic)
what is another name for the intra-articular disc?
meniscus
what are intra-articular discs made of?
fibro-cartilage
where are intra-articular discs found?
in joints where there are rotary movements
what are bursae?
closed sacs lined with synovial membrane, lubricated with fluid
where are bursae found?
where friction occurs eg between bone + skin and tendons + bone
what are synovial sheaths?
specialised bursae that surround tendons there they are subject to pressure
where are synovial sheaths found?
in tendons found in the hand and foot
what joint allows movement in 3 planes?
ball and socket
what joint allows movement in 1 plane?
hinge
what factors influence stability? (3)
shape of bones, strength and position of ligaments, tone of surrounding muscle
what to tendons do?
connect the muscle to the bone
what is osteoarthritis?
a degenerative disease, wear and tear
what does osteoarthritis effect?
the articular cartilage and weight bearing joints
what is rheumatoid arthritis?
autoimmune disease that can affect all synovial joints
what does rheumatoid arthritis do?
changes in synovium lead to destruction of the articular cartilage
how many muscles are in the body?
650 (approx 40% body weight)
by how much do muscles shorten by when their cells are stimulated by nerves?
a third of their length
what kind of tissue is muscle?
primary
name the 3 types of muscle
skeletal, visceral and cardiac
skeletal muscle is…
voluntary and striated
visceral muscle is…
involuntary and smooth
cardiac muscle is…
involuntary and striated
components of the leg from surface inwards… (5)
skin, superficial fascia, deep fascia, muscle, bone
what does deep fascia do?
divides the limb into compartments eg anterior and posterior in the arm
compartments contain groups of muscles that…
share a function
within a functional group there is… (3)
prime mover, synergists, antagonists
what does a prime mover do?
the main participant in a movement
what does a synergist do?
other muscles in the group that work with prime mover
what does an antagonist do?
opposes the movement of the primer mover which gives stability and resistance
how are muscle fibres arranged?
into bundles or fasiculi
what are muscles associated with?
extensive connective tissue coverings that support nerves and capillaries
what is the epimysium?
the dense sheath on the surface surrounding all the fascicles
what is the perimysium?
lies between the fasiculi
what is the endomysium?
separates the muscle fibres
what does the myosatellite cells give rise to?
myoblasts
what do myoblasts mature into?
myocytes
what inhibits the process of differentiation?
myostatin
muscle consists of cells that when stimulated by nerves…
contract causing tension bringing about movement at synovial joints
where are the 2 places muscle can attach to?
directly to periosteum via fleshy muscle fibre or indirectly to periosteum via tendons
