MS System: Joints and Muscles Flashcards
Function of joints?
facilitate growth and transmit forces
Classification of joints by movement?
- synarthroses - barley move
- amphiarthroses - move a little
- diarthroses - very movable
Classification of joints by soft tissue structure?
- fibrous
- cartilaginous
- synovial
Fibrous joints?
joined by dense fibrous network
- sutures - between skull and vault bones
- syndesmosis - fibrous membranes between bones - radioulnur (ankle area)
- gomphosis - peg and socket - teeth in jaw
Cartilagenous joints?
> primary cartilaginous joints - synchondrosis
bone-hyaline cartilage-bone
secondary cartilaginous joint - symphysis
bone-hyaline cartilage-fibrocartilage-hyaline cartilage-bone
Primary cartilaginous joints?
synchondrosis
bone-hyaline cartilage-bone
- very strong, no movement
- first rib and sternum, epiphyseal plates in growing bones
Secondary cartilaginous joints?
symphyses
bone-hyaline cartilage-fibrocartilage-hyaline cartilage-bone
- joints of sternum, intervertebral disks, pubic symphysis
- joints of midline
- limited movement
Synovial joints?
- very movable
- friction free
Features of synovial joints list? (8)
- fibrous capsule
- articular cartilage
- synovial membrane
- synovial fluid
- intra-articular disk
- bursae
- synovial sheaths
- articular cavity
Fibrous capsule?
- collagen fibres
- may be thickened along lines of stress to form ligaments (restrict movement) intrinsic and extrinsic ligaments
Articular cartilage?
- hyaline cartilage
- creates frictionless surface
- poor blood supply - slow healing
Synovial membrane?
- collagenous tissue that lines fibrous capsule
- secretes synovial fluid
Synovial fluid?
- hyaluronic acid, lubricant, few phagocytic cells
- reduces friction between articular surfaces
- alignment go glycoprotein molecules changes with excersice - decreases viscosity so that lubrication improves - thixotropic
- provides nutrients and o2 for articular cartilage
- removes waste
Intra-articular disk? (meniscus)
- fibre-cartilage
- found in joints with rotatory movements
Bursae?
- prevent rubbing
- closed sacs lined with synovial membrane - lubricated with fluid
- found where friction occurs - between skin and bone, tendons and bone
Synovial sheaths?
- specialised bursae that surround tendons where they are subject to pressure
- found in hand and foot
What determines the range of movement of a joint?
shape of articular surface
- ball and socket joint - three planes
- hinge joint - one plane
What factors influence joint stability?
- shape of bones
- strength and positions of the ligaments - stretching
- tone of the surrounding muscles - continuous contraction of muscle
What is osteoarthritis?
degenerative disease
- articular cartilage
- weight bearing joints
What is rheumatoid arthritis?
autoimmune disease
- changes in synovial lead to destruction of articular cartilage
What are the three types of muscle?
- skeletal - voluntary, striated
- visceral - involuntary, smooth
- cardiac - involuntary, striated
Function of deep fascia?
divides limbs into compartments
What are the muscle components of a functional group?
compartments contain groups of muscles that share a function
- prime mover - main participant in movement
- synergists - other muscles
- antagonists - oppose movements for stability
How are muscle fibres arranged?
in bundles or fasciculi
The connective tissues that cover muscles?
support nerves and capilaerire
> endomysium - separates muscle fibres
> perimysium - lies between fasculi
> epimysium - dense sheath on surface
Skeletal muscle differentialtion?
myosatelite cells differentiate into myoblasts which mature into myocytes
What inhibits the process of skeletal muscle differentiation?
myostatin
How do muscles cause movement?
when stimulated by nerves muscles contract causing tension that causes movement
How do muscles attach to bone?
- directly to periosteum via fleshy muscle fibres
or - indirectly to periosteum via tendons
