Introduction: Literature pertaining to failed fusions and revision pediatric spondylolisthesis surgery is scarce. Salvage strategies in the form of iliac screws for the commonly occurring S1 screw failures have been described; however, limitations exist. We illustrate the utilization of S2AI screw as a salvage strategy in revision pediatric spondylolisthesis surgery.

Methods: Three consecutive surgically managed pediatric high-grade spondylolisthesis patients were retrospectively analyzed. Pre-operative, post-operative and follow-up clinical and radiological data pertaining to the cases was retrieved from the hospital electronic database.

Results: All three patients were petite, pre-pubertal females (Risser grade I) presenting with symptomatic Meyerding grade IV spondylolisthesis at the L5-S1 level. As per the SDSG classification system, case 1 was type 6; while, cases 2 and 3 were type 5. Patients underwent successful operative management with wide decompression of neural structures, reduction of spondylolisthesis (to maximum possible extent) and posterior fusion. Case 1 had failed fusion at 12 months follow-up due to bilateral S1 screw breakage. The distal fixation at revision was achieved by utilizing S2-alar iliac screws as salvage strategy in order to get pelvic fixation into the construct.

Conclusions: Certain issues like incorporation of pelvic support in primary surgery remain contentious due to the thin built and prominent pelvic bones encountered in children. The S2 alar-iliac screw may be safely considered as a salvage procedure in cases of failed fusion or may even be incorporated to enhance the strength of the construct (by including pelvic support) in high grade pediatric spondylolisthesis in unbalanced spines.

Patient Care: We highlight the the inclusion of a S2 alar-iliac screw as a salvage procedure in cases of failed fusion. It may even be incorporated to enhance the strength of the construct (by including pelvic support) in high grade pediatric spondylolisthesis in unbalanced spines.

Learning Objectives: Management of high grade pediatric lumbar spondylolisthesis

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