2. Kinematics.pdf

TOPIC 2: KINEMATIC PRINCIPLES OF JOINT MOVEMENT Kinematics Is a branch of mechanics that describes motion of a body without regard to the forces or torques that may produce the motion.l Osteokinematics Motion of bones relative to the three cardinal planes of the body: -Sagittal -Frontal -Horizontal...

TOPIC 2: KINEMATIC PRINCIPLES OF JOINT MOVEMENT Kinematics Is a branch of mechanics that describes motion of a body without regard to the forces or torques that may produce the motion.l Osteokinematics Motion of bones relative to the three cardinal planes of the body: -Sagittal -Frontal -Horizontal Arthrokinematics Describes the motion that occurs between the articular surfaces of joints: -Roll -Glide -Spin Osteokinemtics Open kinetic chain: the distal segment can rotate against the relatively fixed proximal segment. Closed kinetic chain: the proximal segment can rotate against the relatively fixed distal segment. Arthrokinematics Motion that occurs between the articular surfaces of joints Cannot be produced voluntarily in isolation. Include: -Glide -Roll -Spin -Traction -Compression Concave and convex rule Joint congruency: how well joint surfaces match/fit More congruent —> More sliding More incongruent —> More rolling While concave surface moves on convex Surface (B): Rolling and Gliding on the same direction Same direction as osteokinematic While convex surface moves on concave surface (A): Rolling and gliding on opposite ways. Rolling goes the same direction as osteokinematic Plane: There is no movement axis. Sliding movements in all directions. Hinge joint: Allows rotations around the transversal axis of the joint. Pivot: Allows rotations around the longitudinal axis of the bone. Elliptical: Moves around the transversal and anterior-posterior axis, but not around the longitudinal axis. Saddle: It moves around the transversal and anterior-posterior axes, not longitudinal. Spheroid: 3 axis