Laundry Somebody has to do it! (Opening the Lid to my washing machine)

     Everyday I do laundry and in doing so I have to open the lid to the washing machine. When I face my washing machine my arms are down by my sides with my elbows extended and my shoulders adducted. When I place my hands on the lid of the washing machine my elbows flex and my hands and forearms supinate. As I continue to fully open the lid my elbows extend, my hands and forearms pronate, and my shoulders flex. The movements of my elbow and shoulder happen in the sagittal plane about the frontal axis, while the rotation of the forearm occurs in the horizontal plane along the vertical axis. The osteokinematics of the elbow start in an extended position, move through flexion, then end in extension. In terms of arthrokinematics, in regards to what happens during the flexion part of this movement the articulation of the humeroulnar joint takes place between the convex distal end of the humerus with the concave proximal end of the ulna. When my elbows are in flexion the proximal end of the ulna glides along the distal end of the humerus anteriorly. Also during elbow flexion the articulation between the proximal end of the radius glides over the distal end of the humerus anteriorly. The prime mover of the elbow for flexion when the forearm is supinated are the biceps brachii and the movement is a concentric contraction. When my elbows are extended the artrokinematic articulation of the humeroulnar joint still occurs between the distal end of the humerus and the proximal end of the ulna but this time the ulna glides along the humerus in a posterior direction. Same can be said for the articulation of the humeroradial joint, during extension the radial head glides along the distal end of the humerus in a posterior direction. During the extension phase of this movement the elbows are in an eccentric contraction.