We need to know 2 things so that we can understand the relationship.
1. Who is Shiva
2. What is rudraksha
3. When did the name rudraksha came into picture.
1. Shiva is the name of Supremesoul. Supremesoul is only one and we tell him Paramatma. He is supremesoul because he is the supreme of all our souls. Our Father who created us ( I am a soul). Many have given many names even in Hinduism. But his real name is Shiva. Who does not have a body and so Hindus pray him as a semi circular egg shape which is the shape of the soul. Soul is point of light and the aura around makes an Egg structure.
2. What is Rudraksha ? - is pointing to Rudra and aksha. Rudra is another name given to Shiva. Supremesoul when comes and meet us on earth ( we are souls in a body, hava a form), So he takes a lighter body so that he can communicate. That time we call him Rudra. The meaning and other things here is known to all souls, they just have to think and the answer should come automatically from within or from Shiva.
Rudraksha is the highest ranked children who help Shiva during the Yuga creation / change. They are the eyes of Shiva as God makes change/ brings changes, with them. Paramatma tells in hindi 'Mein tumhe mere palkon par betha ke lunga".
3. Rudraksha name came into picture during the Yuga change. So Yuga comes after previous Yuga. it is a continuation of drama / repeataion of drama. So Rudraksha is created during the starting of the Yuga or during the closing time of previous Yuga. And the representation is in the form of Rudraksha beads.
So we are referring rudraksha with ourselves when we had become equal to rudra with the help of Supremesoul and had done work that was asked us to do.
All these knowledge is part of the soul. So Many soul should have this knowledge hidden within.