L5 Partial Pedicle Subtraction Osteotomy in High Pelvic Incidence Patients: A New Way to Manage Lordosis

Introduction: Numerous corrective osteotomy techniques have been reported in lumbar area. Owing to mechanical difficulties and reputation of higher neurological risk, L5 pedicle subtraction osteotomy (PSO) has been poorly used and described. Until now, there was no reported specific method of PSO in L5 to manage the shape of the lordosis with respect of local anatomy. The objective of this study was to describe a new partial PSO technique in L5 to manage the lower arc of lordosis in high pelvic incidence patients with fixed sagittal imbalance. Materials and Methods: We describe, here, the surgical technique for a partial PSO at L5 level and the associated technique of instrumentation and correction of lordosis. Results: Two different cases were reviewed retrospectively to illustrate this new technique to manage lordosis. The described technique is feasible either in first intention or in a revision surgery. Radiologic results on lordosis and sagittal balance are exposed. Conclusion: A partial resection of the pedicles at L5 is often sufficient to create enough lordosis, maybe more effective than complete L3 and L4 PSO for restoration of sagittal balance and less aggressive than complete L5 PSO.