Revision extension to the pelvis versus primary spinopelvic instrumentation in adult deformity: Comparison of clinical outcomes and complications

Objective: To evaluate the outcomes and complications of patients with adult spinal deformity treated in a primary versus revision fashion with long fusions to the sacropelvis.

Methods: A retrospective review was performed of a multicenter consecutive series of patients with adult spinal deformity requiring fusion to the sacropelvis, either primarily or as revision, with minimum 2-year follow-up. Clinical (Scoliosis Research Society [SRS] 22 questionnaire) and radiographic parameters (including sagittal vertical axis [SVA], coronal Cobb angle, lumbar lordosis, and thoracic kyphosis) were compared between the groups.

Results: There were 63 patients who met inclusion criteria; mean patient age was 51.9 years, and mean follow-up was 43 months. Patients requiring primary fusion were older (58.0 years vs. 49.5 years, P = 0.01) and at baseline had a lower SVA (2.1 cm vs. 6.8 cm, P = 0.01) and greater thoracolumbar Cobb angle (51.2 degrees vs. 36.5 degrees, P = 0.003). At last follow-up, patients undergoing primary fusion and patients undergoing revision treatment had similar SVA (2.9 cm vs. 1.8 cm, P = 0.32) and lumbar lordosis (-42.3 degrees vs. -43.4 degrees, P = 0.82); patients undergoing revision treatment had more favorable SRS 22 scores (3.65 vs. 3.14, P = 0.005). There was no statistical difference in complication rates between the groups (44.4% vs. 35%, P = 0.68).

Conclusions: Patients requiring revision extension of instrumentation to the pelvis can be treated with the same expectation of radiographic and clinical success as patients treated primarily with fusion to the sacropelvis. The complication rate for the revision procedure is not insignificant and may be similar to a primary procedure that includes pelvic fixation.