intro to MSK system Flashcards
what are the main functions of bone?
- structural support & protection
-levers for movement - blood cell formation
-storage reservoir for Ca2+
what are the 2 types of bone?
- compact
- cancellous - ie spongy
what shapes is bone classified by?
-long
-short
-flat
-irregular
-sesamoid
what are the main parts of long bone?
-
diaphysis - the main part of the bone that runs from proximal to distal ends
-Epiphysis - terminal end of long bone
-periosteum- membrane of blood vessels and nerves that wraps around bone
-medullary cavity- hollow part of bone that contains bone marrow
in terms of movement, what are the roles of joints, ligaments and muscles?
- joints allow movement
-muscles create movements - ligaments / joint capsule limits movement
compare the diaphysis vs the epiphysis
- epiphysis - the end part of a long bone
- diaphysis - shaft or central part of lone bone
what are fibrous joints?
the joints in which the bones are connected by fibrous tissue
IMMOVABLE JOINTS- they don’t allow movement
what are cartilaginous joints?
joints in which the adjacent bones are joined by cartilage
what is the difference between primary and secondary cartilaginous joints?
- primary - where 2 bones are joined by hyaline cartilage
- secondary - 2 bones are joined by fibrocartilage in the form of a disc
what are synovial joints?
- they are freely moveable joints
- articulating bones are united by capsule outer fibrous layer and an inner synovial membrane layer
what is an example of a primary and also a secondary cartilaginous joint?
- primary - first rib joined to manubrium by hyaline cartilage
- secondary - pubic symphysis in pelvis
what are the different types of synovial joints?
- ball and socket joint
-hinge joint
-pivot joint
-pivot joint
-gliding joint
Describe ball and socket joints
- allow the greatest range of movement - ie movement within 3 planes
-convex surface fits into concave shape
what are 2 examples of ball and socket joints?
-shoulder
-hip
Describe the hinge joint
- allows movement around 1 axes, in one plane
- one surface of the bone is spool like and the other surface of the other bone is concave
what is an example of a hinge joint?
the elbow
Describe the pivot joint
- allows movement around 1 axes/ in 1 plane
-surface is shaped like a ring and the other surface is shaped so that** it can rotate within the ring**
what is an example of a pivot joint?
atlantoaxial joint between C1 and C2 vertebrae
Describe a saddle joint
- allows movement around 2 axes/ within 2 planes
-bones have convexity and concavity to its surface - the convexity of the bone fits into the concavity of the other bone
what is an example of a saddle joint?
the sternoclavicular joint
describe the condyloid joint
-allows movement around 2 axes/ within 2 planes
- one bone is concave and the other is convex
Describe a plane/gliding joint
-allows movement to occur within a plane but does not occur around an axis
- surfaces of the bone are usually flat
what is an example of a plane/gliding joint?
the carpal bones of the wrist
what are the 3 major functions of the muscular system?
- producing movement
-heat production
-maintaining posture
what are the 3 ways that a muscle can attach to a bone?
1- directly
2- via a tendon
3- via an aponeurosis (flat tendon)
what is an aponeurosis?
a sheath of fibrous tissue
what is a tendon?
inelastic bundle of collagen fibres
what is the origin in terms of muscle attachment?
the more proximal end of the muscle attachment (ie closer to the trunk)
what is the insertion end of the muscle attachment?
the more distal attachment (further away from the trunk)
what is an agonist in terms of muscle movement?
the prime mover- the muscle primarily responsible for a given movement
what is an antagonist in terms of muscle movement?
- the muscles that perform the opposite actions to the agonist
- they are crtical for proper posture & controlling and finishing movements
what are the antagonist movers important for?
-critical for proper posture
-controlling and finishing movements
what are the synergists in terms of muscle movements?
-the synergists assist the agonist in creating movement
what are stabilisers or fixators in terms of muscle movement?
-they hold 1 segment still so a specific movement in an adjacent segment can occur
what is an isometric contraction?
-static contraction of the muscle without any visible movement in the angle of the joint
what is an example of an isometric contraction?
- doing a bicep curl, but holding the dumbbell in a constant / static position rather than actively raising or lowering it
what is a concentric contraction & give an example?
in a concentric contraction, the force that the muscle is producing (tension) rises to meet the resistance (load), then remains stable as the muscle shortens
- example: bicep curl
what is an eccentric contraction?
-the muscle lengthens as the resistance become greater than the force that the muscle is producing
what are examples of eccentric contraction?
- lowering the barbell back to the ground after a deadlift
-lowering your torso back down to the ground after a sit up
what is the full range of muscle work?
the shortest to the longest possible length
what is the outer range of muscle work?
it is between the longest length and midway point of range
what is the inner range of muscle work?
between the shortest length and midway point of range
what important protein is important in the structure of a tendon?
type 1 collagen
what is the function of type 1 collagen in a tendon?
it transmit forces from muscle to bone
do tendons contract?
no
- part of the contractile unit, but it is a distinct tissue from muscle
do tendons contain elastic fibres?
no
what is the function of a ligament?
-attaches bone to bone
-provides passive stability to a joint - ie it limits too much movement
what does the ligament structure contain?
-collagen - 70-8-%
- elastic fibres
Describe the 2 layers of a joint capsule
- outer fibrous layer - flexible, inelastic and supported by ligaments
-inner synovial layer - synovial membrane
what is the synovium?
- specialised connective tissue membrane that lines the inner surface of synovial joint capsules
what are bursae?
small fluid filled sac between bones and tendons
what is the function of bursae?
- lubricating device - therefore reduces friction
what is the function of the fat pads in a synovial joint?
- they serve as a cushion between the bones
