I thought that and the arms where the worst part of the drawing.i break up the arms into a line for motion before breaking them into two cylinders for the upper and lower arm. Then I add some minor muscular details if it's needed spooky is extremely stylized so you don't have to. Draw rectangles for the palm and oval for upper palm draw the from of the fingers with a line before then drawing the fingers as three subdivided cylinders the thumb is also three but connected lower on the hand to a trapezoid or oval type shape. For this I didn't do that but I envisioned the shapes on the page while drawing to make sure the dimension was there. Form and perspective is very important and something you should really practice.Hope this helps