Stand-Alone Rod Augmentation for Instrumentation Failure after Pedicle Subtraction Osteotomy: A Case Report with a 2-year Follow-up

Background: Revision surgery of spine can be a complex procedure and has known complications. It involves hardware revision, removal of scar/callus tissue, realignment of sagittal balance, and anterior augmentation. However, through this report, we aim to demonstrate that a stand-alone rod augmentation at the failure site without removal of scar/callus tissue and/or anterior fixation can achieve excellent results in select cases.   Case Report: A 66-year-old woman underwent L2 pedicle subtraction osteotomy (PSO) + T9-iliac fixation for fixed sagittal imbalance and osteoporotic collapse of L3. One year later, she developed progressive axial lumbar pain and difficulty in mobilization. The patient was diagnosed with pseudoarthrosis and instrumentation failure and underwent revision spine surgery with stand-alone rod augmentation. She had an uneventful rehabilitation and showed complete radiographic union and excellent clinical outcome in the 2-year follow-up.   Conclusion: Stand-alone rod augmentation can provide stable posterior construct to prevent future pseudoarthrosis and/or instrumentation failure after revision spine surgery in selected cases. Anterior augmentation or resection dural scar tissue or dissection through callus tissue is not always necessary.