In Kabbalah it is taught that a person is surrounded by four angels: On the right is Michael the angel of Kindness; on the left, Gavriel, the angel of strength; in front, Uriel, the angel of light; and behind, Raphael, the angel of healing. It's apparent why the angel of light is located at the front since our intellect which 'sheds light' on our world is seated chiefly at the front of the head, but why is the angel of healing associated with the back?
It is taught that 'one with his hands tied behind his back cannot free himself'. He needs someone else to untie the rope. This is a metaphor for human limitations in general. Because subjectivity tends to blind one to personal faults or prevents one from viewing them accurately, an objective observer is often needed to identify one's problem and to advise on how to correct it. Healing or general correction is thus related to one's back where one can't see and others are required to assist.
In skateboarding one is often unable to see his own errors when performing tricks. This may be because they're unable to see themselves performing the trick from the outside, because their self-love blinds them from seeing their flaws and errors, or because they lack the expertise to identify their mistakes. By asking another skater - preferably a caring, honest, and proficient one - to observe one's technique and to comment, allows for dramatic correction of technique and rapid improvement.
In short, go and find yourself a Raphael that skateboards!