Biomechanics Activity Analysis: Washing my Face

Every morning I wash my face. Washing my face in the morning helps me wake up and feel refreshed. When I walk into the bathroom, I face the sink. The first thing I do is reach for my face wash that is placed on the counter of the sink. 

When I reach for my bottle of face wash, my elbow is in an extended position while my shoulder is slightly flexed. In order to grasp the bottle, all of my MCP, PIP, and DIP joints are slightly flexed, and my thumb is abducted around the bottle. After I grab the bottle of face wash, my elbow moves into a flexed position while my shoulder extends to bring the bottle of face wash close to me. 

The movements of flexion and extension at the elbow joint and shoulder joint as well as the MCP, PIP, and DIP joints, occur in the sagittal plane about a frontal axis. The osteokinematics of the elbow are extension to flexion in an open kinematic chain. Regarding arthrokinematics in the elbow joint, the ulna is the concave moving surface which glides and rolls anteriorly on the stable convex surface of the humerus. The prime movers for elbow flexion are the biceps, brachialis, and brachioradialis, which perform a concentric contraction.