Spine cage holder

A cage holder comprising:

• an elongated body comprising a proximal end and a distal end, the elongated body extending from the proximal end to the distal end of the elongated body;
• and
• a tube configured to transfer energy centrally from a proximal end to a distal end of the cage holder, said tube being at least partially enclosed by the elongated body, the tube extending through the elongated body and from the proximal end to the distal end of the cage holder, the tube comprising or consisting of a first material, the tube configured to transfer energy centrally from the proximal end to the distal end through the elongated body, the tube including an elongated shaft removably held in the cage holder, the elongated shaft including a knob at a first end thereof,
• wherein the elongated body comprises or consists of a second material different from the first material, the first material having a greater material density than a material density of the second material, the tube having a greater rigidity or a lower flexibility than a rigidity or a flexibility of the elongated body,
• wherein the elongated shaft is removably held inside the tube, and
• wherein the elongated shaft has a complementary shape to a shape of the tube to fit snuggly inside the tube for a transfer of energy, the elongated shaft being a hollow rod or hollow shaft.