An SFP transceiver cage comprises a mainframe and a rectangular grounding device mounted around a front portion of the mainframe. The apparatus may include a horizontal base with two vertical members, each vertical member being affixed to the horizontal base, with each vertical member having a metal plate affixed to the inner side of each vertical member. By aligning the passage to intersect with the defect in the bone, the creation of the passage itself results in the removal of the defect from the articulating surface of the bone. As the respective optical signals pass through the segment of multimode fiber, they are combined to produce a mode-scrambled optical signal having a substantially-filled numerical aperture that is emitted from the output end of the fiber.