ARTICULAR KINEMATICS: ARTHROKINEMATIC & OSTEOKINEMATIC Flashcards
Areas of biomechanics
Kinematics and kinetics
Definition of kinematics
= branch of mechanics that deals with geometry of motion of objects,
including displacement, velocity and acceleration, without considering forces that
produce motion
Division of movements & description of each
- Rotation: movement that takes place through circular pattern around
pivot (axis of rotation) - Translation: linear motion occurring in a straight and curvilinear line
Definition osteokinematics
= describe angular motions of bone segments in 3 planes of space & which are visible
Plane & axis of each mvt of GH joint
Flexion / extension:
- Plane: sagittal
- Axis: transverse
ABD / ADD:
- Plane: frontal
- Axis: sagittal
Rotation:
- Plane: transverse
- Axis: vertical
Definition of degrees of freedom
= number of directions of angular motion allowed in a joint
Define degrees of freedom (number and type): GH, wrist and elbow
GH: 3 sagittal, frontal and horizontal (= transverse) plane
Wrist: 2: sagittal and frontal planes
Elbow: 1: sagittal
What are the things that restricted the degrees of freedom in translation movement ?
Joint capsule
Ligament
Surrounding structures
Define the possible direction of movements and the corresponding axis
Anterior post = x axis
Medial lateral = y axis
Superior inferior = z axis
What are the functional importance of degrees of freedom
- Joint stability: slight translational adjustments help maintain joint congruency
during motion - Shock absorption: small translations dissipate forces during impact
- Pathological assessment: excessive or restricted translation can indicate injury
(ex: ligament tears in knee)
Definition arthrokinematics
= movement occurring between joint surfaces: accessory displacements between joint
heads in relation to each other occurring during body movements
Name 3 main movements of arthrokinematics
Roll, spin and slide
Definition glide
translatory motion given by sliding of joint surfaces
Definition slide
occurs when a single point on surface of bone end contacts multiple
points on opposite end
Definition roll
occurs when multiple points of joint end contact multiple points of opposite
end
Definition swing
angular motion occurring in same direction of movement of segment under consideration