US Patent 11464649 Expandable spinal fusion cage

The present invention provides a spinal fusion cage that can be inserted between vertebral bodies at the lowest height, and the height thereof may be adjusted with being inserted, such that cages having different heights within a certain range may be replaced by one cage. Therefore, the number of product groups that should be produced is reduced and the amount in stock is also decreased on the manufacturer. In addition, unlike the cage having a predetermined height at a constant interval in the prior art, the height of the spinal fusion cage is linearly adjusted according to a spacing between vertebral bodies of a patient, such that the surgery may be performed at the optimal height according to spinal conditions of the patient.