Biomechanics Flashcards
Class I lever
fulcrum between effort and load, atlantooccipital joint, effort and load in opposite directions
Class II lever
load is between effort and fulcrum, calf contraction at the ankle, overall load and effort in the same direction
Class III lever
(most common) the effort between load and fulcrum, elbow joint, effort and load in the same direction
Synarthroses
Immovable, skull sutures - fibrous joints
Amphiarthroses
Slightly moveable, vertebrae and discs - cartilaginous joints
Diarthroses
freely moveable, knee and shoulder - synovial joints
Ball and socket
shoulder (movement in all directions)
Hinge joint
elbow (opens and closes along one plane)
Condyloid joint
fingers (MCP) , TMJ (everything but rotation)
Pivot joint
rotation around the elbow (ulna and radius) (rotary, one bone that can swivel in a ring formed from a second bone)
Gliding joint
carpal rows (plane joint)
Saddle joint
thumb - CMC joint (move back and forth and side to side)
AC joint
inferior rotation during first aspect of abduction
SC joint
anterior rotation and anterior translation (horizontal abduction); posterior rotation and translation (horizontal adduction)
SI joint nutation and counter-nutation
lumbar extension= SI joint nutates; as lumbar flexes, SI joint counter-nutates and moves posteriorly
Coupled cervical motions
lateral flexion coupled with vertebral body rotation to the same side (LLR=LR), except at C0-1 and C1-2 where it contralaterally rotates (these two segments don’t have vertebral bodies)
Lumbar coupled motions
if extended vertebral bodies rotate to the opposite side of lateral bending (LLR= RR); if flexed vertebral bodies rotate towards the same side of lateral bending (LLR=LR)
Thoracic coupled motions
Same as Lx
Gait cycle stance phase
heel strike, loading response, mid-stance, terminal stance, pre-swing
Gait cycle swing phase
initial swing (toe-off), mid-swing (foot clearance), terminal swing
Heel strike foot position
supinated position, strong rigidity in arches
Mid-stance foot position
pronation, shock absorber
Terminal stance foot position
supination, more rigid again
Swing phase position
toe off, maximal hip extension, swing phase allow bringing through
Thoracic facet orientation
coronal
Lumbar facet orientation
sagittal
Shoulder abduction/adduction
for the first 90 degrees of shoulder abduction, there is an inferior rotation of the AC joint
from 90-180, there is superior translation of the clavicle in addition to inferior rotation/tipping of the scapula
Shoulder horizontal abduction
when the shoulder is horizontally abducted there is posterior rotation of the SC joint in addition to anterior translation of the joint
Shoulder horizontal adduction
when the shoulder is horizontally adducted there is anterior rotation of the SC joint in addition to posterior translation of the joint
what type of joint is the first CMC
saddle
what type of joint is MCP
condyloid
where is the most rotation in the c-spine
C1-C2
where is the most flexion in the c-spine
C0-C1
15 year old had apophysis of ileum fused, how much longer till full fusion
2-3 years, fully fused by 16 years of age
shoulder at 90, arm at 90 what plane are you testing external rotators in
sagittal
gymnast rolling forward, what plane of motion is this in
sagittal
abductors/adductors are tested in what plane
frontal/coronal
weak leg abduction, what plane of motion
coronal/frontal
