P60. Influence of osteoporosis on clinical outcomes and revision surgery rates for mechanical complications following corrective fusion surgery for adult spinal deformity

Background Context Corrective fusion surgery for adult spinal deformity (ASD) often involves multiple implants to align and stabilize the spine and pelvis. However, bone fragility in the spine or its adjacent areas may lead to mechanical complications, influencing clinical outcomes. Purpose The purpose of the study was to compare the health-related quality of life (HRQOL) and revision surgery rates due to mechanical complications in ASD patients undergoing corrective fusion, both with and without osteoporosis. Study Design/Setting Retrospective cohort study. Patient Sample Patients (aged 40 years and above) who underwent corrective fusion from thoracic spine to the pelvis for ASD between 2010 and 2017, with a minimum follow-up of 5 years postsurgery. Outcome Measures SRS-22r, ODI scores, and revision surgery rates for mechanical complications Methods ASD patients were classified into an osteoporosis group based on a T-score ≤ -2.5 at the femoral neck, or preexisting fragility fractures of the spine or proximal femur. We investigated preoperative and 5-year postoperative SRS-22r, ODI, and revision surgery rate for mechanical complications within 5 years after surgery, and compared the results between groups without and with osteoporosis. Results The study included 139 patients (125 females, average age 67.2 years). In the non-osteoporosis group (n=75, average age 65.4 years) and the osteoporosis group (n=64, average age 69.4 years), SRS-22r function improved from a preoperative mean of 2.7 vs 2.4 (no osteoporosis group vs osteoporosis group) to 3.5 vs 3.1 at 5 years postoperatively. Pain improved from 3.0 vs 3.1 preoperatively to 4.0 vs 3.7 at 5 years postoperatively, and ODI improved from 41 vs 44 preoperatively to 23 vs 31 at 5 years postoperatively in both groups (p<0.001). No significant difference was observed in SRS-22r Function and ODI changes between the groups (P>0.05). However, the improvement in SRS-22r Pain was significantly greater in the nonosteoporosis group (no osteoporosis group vs osteoporosis group) (1.0 vs 0.6, p=.046). SRS-22r Satisfaction scores at 5 years were 3.6 and 3.4, respectively, with no significant difference (p=.101). The 5-year revision surgery rate for mechanical complications was 17.3% in the nonosteoporosis group versus 32.8% in the osteoporosis group (p=.034). Conclusions Corrective fusion surgery for ASD, including those with osteoporosis, showed improvement in function and pain after 5 years. However, the presence of osteoporosis negatively impacted pain improvement and increased the likelihood of revision surgery for mechanical complications. FDA Device/Drug Status This abstract does not discuss or include any applicable devices or drugs.