Introduction: Hardware failure is a major complication after correction of adult spinal deformity. While few studies have reported a correlation between surgical site infection and hardware failure, none has irrevocably demonstrated the existence of such a link.

Methods: Patients charts were reviewed for those undergoing spine surgery between 1/1/2006 and 10/3/2017. Inclusion criteria included age =18 years and surgery performed for the correction of thoracolumbar scoliosis. Data collected included demographics, medical comorbidities, surgical indication, operative characteristics, postoperative complications (including infection), long-term complications (including hardware failure), and revision surgery.

Results: 532 patients met criteria for inclusion. Of these, 20 (4%) had surgical site infection. There were no demographic or clinical characteristics associated with surgical site infection. Number of fused levels and operative time were similar between groups. Hardware failure occurred in 68 (12.8%) patients, 10 of whom (15%) had surgical site infection, while of the 464 patients with no hardware failure, only 10 (2%) had surgical site infection (p=0.003). Of the 20 patients with surgical site infection, 10 (50%) had hardware failure, while in the 512 patients with no infection, only 58 (11%) had hardware failure (p=0.002). Patients with infection also experienced significantly shorter time to hardware failure (p=0.015), higher need for revision surgery (p<0.001), and shorter time to revision surgery (p=0.001).

Conclusions: Our study demonstrates that early surgical site infection significantly increases the risk of instrumentation failure in patients with thoracolumbar scoliotic deformity, shortens the time to hardware failure, increases the rate of revision surgery, and decreases time to revision surgery.

Patient Care: Our findings inform neurosurgeons treating patients with adult spinal deformity who develop a surgical site infection following corrective surgery, and guide their anticipatory monitoring of patients in long-term follow-up.

Learning Objectives: By the conclusion of this session, participants should be able to: 1) Describe the relationship between infection and hardware failure 2) Anticipate the need for revision surgery in patients with surgical site infection

References: Adult spinal deformity; complication; instrumentation failure; surgical site infection; revision surgery