Watching
ballet dancers, I can be convinced that they have elbows unlike mine. Their
elbows are not pointy or edgy or rough but seamlessly fluid, almost as though
they have no bony structure at all. Dancers achieve this artistic skill through
disciplined movements of the arms, a series known as port de bras, translated
as "carriage of the
arms".
What
dancers learn is that each joint of the arm has a particular range of motion,
thanks to its shape and attachments. The elbow can flex, extend, pronate and
supinate. The upper arm joint is the most freely moving joint in the body, and
the joint where the collarbone meets the breast bone has small but critical
horizontal and rotational movements. These movements, in conjunction with wrist
movements, create the flowing sequence of port de bras.
Just as the
well-trained dancer deceives me, pianists can deceive me into thinking I am
seeing movements that are not humanly possible. As explained in the previous
post, there is no fully circular movement potential in the structure of the
wrist. But the upper arm does have circular potential. Put this in combination
with the semi-circular rotation at the elbow, and it is a short leap of faith
to translate these movements down to the wrist.
The
problem with this optical illusion is that pianists may attempt to make
movements with the wrist that happen in other joints of the arm. This is both
limiting and potentially dangerous. Because the nerves that run the fingers
move through the carpal arch on the underside of the wrist, putting stress on
the wrist can compress these nerves. Potential outcomes are pain, numbness,
tingling, and limited range of motion.
If you know the
ranges of motion for the four main joints of the arm, you will be able to
determine the actual movement from the perceived movement. With that
information, you will be "armed" to create artistic illusions without
fear of injury.