Biomechanics Activity Analysis

   Everyday I fill up my water cup with a pitcher of water. My starting position is having my arms relaxed at my side with my right elbow bent around 90°, my wrist is extended and my MCP, PIP, and DIP joints are all flexed around the handle of the pitcher. The final position would have my right shoulder abducted and internally rotated, my wrist flexed and my MCP, PIP, and DIP joints still flexed. The wrist flexion and shoulder flexion occur in the sagittal plane about the frontal axis. The internal rotation of the humerus occurs in the horizontal plane about the vertical axis. The osteokinematic action at the wrist joint is flexion; it is an angular open kinematic chain motion. For the arthrokinematics, the carpal bone which is convex glides and rolls in opposite directions on the radius which is a concave surface. The prime movers are extensor carpi radialis longus, extensor carpi radialis brevis, and extensor carpi ulnaris which would be an eccentric activation acting as decelerators, since the action of pouring the water would happen in the direction of gravity.