The Biomechanics of Lameness Flashcards
safety factor =
maximum stress a structure withstands until breakage over stress it is most likely to undergo during its lifetime
Constraints during locomotion:
need to support against gravity
force only produced when limb in contact with ground
types of force
Tension
Compression
Bending
Shear
What happens when you use your leg on real surfaces that differ in stiffness
Leg gets stiffer as surface is more compliant
flexor tendon muscles - properties
highly pennate
muscle fibres ~ 1cm
limited capacity for length change
bending strength higher or lower for one large bone
higher
advantages of having bone fusing in lower limbs
lighter limb, shorter swing time, less mechanical
energy
functions of a joint
relative movement of limb segments
shock absorbers
hoof - mechanical function
shock absorption
support and grip
propulsion
hoof - constraints
resistance to abrasion
protection of sensitive structures
hoof - protective mechanisms
shape of solar surface allows heel movement
suspension of distal phalanx - forces transferred via distal border of hoof wall
digital cushion: shock absorption and frog movement
hoof sliding
rotation + translation of the DIP joint
which phase of the stride cycle is the highest load present
stance phase
4 phases of the stance phase
1st impact
2nd impact
support, large vertical force
breakover/propulsion
1st impact
large accelerations, low forces:
likely to result in bruising to the soft tissues
2nd impact
low acceleration, high forces:
important to allow for a ‘natural braking action’
