Lumbar stand-alone interspinous fixation without decompression or bone graft: A 14-year cautionary case of late mechanical failure

Background: Stand-alone spinous-process fixation devices have been used as a minimally invasive option for selected lumbar degenerative conditions. However, very late implant-bone interface failure is not well documented in the clinical literature. Case Description: A 54-year-old male without osteoporosis underwent stand-alone clamp-type metallic interspinous fixation at the L4/5 level for axial low back pain with stable Grade I degenerative spondylolisthesis. Fourteen years later, he developed severe motion-provoked focal pain at the prior surgical site. Dynamic radiographs demonstrated marked bony erosion/osteolysis at the instrumented level with implant malfunction. Implant removal resulted in substantial symptom relief. Conclusion: This case highlights very late failure of stand-alone clamp-type metallic interspinous fixation device at the L4/5 level. Studies revealed progressive peri-implant osteolysis/erosion with loosening causing mechanical low back pain. The failure of this interspinous device underscores the need for long-term patient surveillance following the placement of a stand-alone interspinous process fixation device.