GROWING RODS AND METHODS OF USE

摘要

Hydraulically expandable spinal rods and methods of use thereof are disclosed. The spinal rod may include a piston rod, a static rod, and a hydraulic pressure chamber for accepting hydraulic fluid and causing the piston rod to move in an expansion direction relative to the static rod. Upon connection of the piston and static rods to a patient's spinal column, the hydraulic spinal rod may be expanded to aid in correction of an underlying spinal deformity.

主权项

1. A spinal rod comprising:
a first rod portion having an elongate rod section adapted for connection with a first fixation element implanted in a first vertebra, the first rod portion including an internal hollow cavity defined by an internal wall surface; a second rod portion having an elongate rod section adapted for connection with a second fixation element implanted in a second vertebra, wherein the second rod portion is inserted within the internal cavity of the first rod portion and is axially movable relative to the first rod portion within the internal cavity in an expansion direction, the rod sealingly engaging the internal wall surface and thereby defining a hydraulic pressure chamber, wherein the hydraulic pressure chamber is fluidly sealed off from the internal hollow cavity; an injection port and a flow channel in fluid communication with the hydraulic pressure chamber; and a locking mechanism engageable with the second rod portion, the locking mechanism being effective to lock the second rod portion relative to the first rod portion, wherein the locking mechanism includes a release mechanism allowing for disengagement between the locking mechanism and the second rod portion to permit movement of the second rod portion in a contraction direction opposite the expansion direction.