Protrusion of a rod into the spinal canal 10 years after segmental lumbar spine surgery

The objective of this article is to report an unusual case of a spinal rod that protruded into the spinal canal after lumbar spine surgery. Only 4 cases of spinal rod migration with protrusion into the spinal canal have been reported. This is the first report of a case involving the use of posterior low lumbar segmental instrumentation with a screw–rod system. The left side of the rod gradually migrated and finally protruded into the canal and compressed the cord. A 60-year-old woman presented with pain and numbness of the posterior aspect of the left leg after a long-distance walk. Intermittent claudication became worse, and she developed pain and numbness in the perineal region. An x-ray showed that the left side of a spinal rod among the segmental spinal instruments that had been placed 10 years previously had protruded into the spinal canal. We removed the rod and decompressed the canal at the level of L5-S1. The patient became totally asymptomatic. Rods used as spinal instrumentation have the possibility of protruding into the spinal canal and endangering the nervous system. Long-term follow-up with radiological examinations should be conducted upon completion of spinal operations conducting using instrumentation.