Statics and Dynamics of the Musculo-Skeletal System Flashcards
What is a static ?
A static is a situation which involves a stationary, rigid body in equilibrium.
Why are statics used in Biomechanics ?
Statics are used to take snapshots of a moving body to allow for examination of the internal and external forces.
What are the parts and classes of Levers?
Class 1 - crowbars and pry levers
Class 2 - wheelbarrows
Class 3 - tweezers and majority of muscles.
A lever system consists of a load, fulcrum, a lever and a force. The class of a lever system depends on the order in which these components are arranged.
What are examples of static laws ?
FOR 2D STATICS
sum of forces in x and y = 0
resultant moment in z = 0
FOR 3D STATICS
moments and forces in x,y and z axes are 0
What direction is positive for moment related questions ?
Counter- Clockwise
What is the principle of transmissibility ?
It states that the force acting on a rigid body will produce the same effects no matter where it is as long as it is in the same direction and line of action. Known as Sliding Vectors
What is a Range of Motion (ROM) ?
Range of motion is the measurement of movement around a specific body parts such as bones, joints, muscles or tendons . Good ROM allows for movement in all planes and directions possible to the joint.
What factors may affect ROM?
Pain
Swelling
Genetics
Stiffness
Gender
Joint structure
Age
Activity level
Fat tissue
Body temperature
What is an active and passive ROM ?
Active ROM - patient moving their joint through the ROM by themselves
Passive ROM - practiced on an inactive joint where a therapist moves a patients joint for them.
Both can improved via static or dynamic stretching but active ROM is much more useful in everyday life.
What are the 6 degrees of freedom of motion ?
Surge - Moving forwards/backwards
Heave - Moving Up/Down
Sway - Moving Left/Right
Roll - Tilting Side to Side
Pitch - Tilting forward and backward
Yaw - Tilting left and right.
What is the difference between Kinetics and Kinematics ?
Kinematics is the study of bodies in motion regardless of the cause of the motion. This motion can be linear or angular.
Kinetics is the study of forces or torques which cause motion.
What are rectilinear and curvilinear motion ?
Rectilinear - Motion in a straight line
Curvilinear - Motion in a curved line
What are some examples of sagittal plane motion ?
Flexion - motion which causes the angle between joints to decrease (e.g bicep curl)
Extension- motion which increases the joint angle (e.g tricep extension)
Hyperextension - excessive extension beyond a joints normal ROM e.g arm behind shoulder joint
Dorsiflexion - pointing of toes upward via the ankle joint.
Plantar Flexion - pointing of toes downward via the ankle joint
What are some examples of frontal plane motion ?
What are some examples of transverse plane motion ?
