227. Prospective, randomized, blinded clinical trial comparing PEEK and allograft spacers in patients undergoing ACDF surgeries

Abstract

BACKGROUND CONTEXT The biomechanical qualities as well as osteoconductive, osteogenic and osteoinductive properties of various graft materials have been previously evaluated. There remain questions, however as to whether there are any clinical and/or radiographic outcome differences in the selection of interbody graft types for ACDF. PURPOSE The main objective of the study was to examine clinical and radiological outcomes in patients undergoing ACDF surgeries randomized to receive either PEEK or structural bone allografts. STUDY DESIGN/SETTING A prospective, randomized, blinded clinical trial was initiated at a single center. PATIENT SAMPLE A total of 120 patients were enrolled and randomized. OUTCOME MEASURES All patients were followed for 2 years ± 2 months; radiographic and clinical outcomes were assessed at 3, 6, 12 and 24 months with an additional follow-up at 3 weeks for radiographic assessment. METHODS Patients undergoing one- to three-level ACDF with single anterior plate fixation were randomized (1:1 ratio) to receive either cortical allograft or PEEK interbody spacers. RESULTS Comparing clinical outcomes, no differences in arm or neck pain scores were noted, however there was a statistically significant (< 0.041) improvement in SF-36 PCS scores for the allograft group at all follow-up time points and a tendency towards lower disability scores. Overall, evidence of radiographic fusion was achieved in 87 (91.6%) patients: five (10.2%) and three (6.5%) patients had pseudoarthrosis (p=0.72) in the PEEK and allograft groups, respectively. At 24 months follow-up time, any cervical or segmental alignment restoration achieved with surgery was lost and no statistically significant changes were detected when all levels of surgery were included. Likewise, there were no statistically significant differences between the groups for anterior or posterior body height measurements at the 24 months follow-up. Approximately 20% of patients had anterior and posterior subsidence, all grade 0 regardless of the group assignment. CONCLUSIONS Comparable radiographic outcomes were observed for patients undergoing one- to three-level PEEK vs allograft-assisted ACDF surgeries. There was a tendency for improved clinical outcomes in the allograft patient group. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs. The biomechanical qualities as well as osteoconductive, osteogenic and osteoinductive properties of various graft materials have been previously evaluated. There remain questions, however as to whether there are any clinical and/or radiographic outcome differences in the selection of interbody graft types for ACDF. The main objective of the study was to examine clinical and radiological outcomes in patients undergoing ACDF surgeries randomized to receive either PEEK or structural bone allografts. A prospective, randomized, blinded clinical trial was initiated at a single center. A total of 120 patients were enrolled and randomized. All patients were followed for 2 years ± 2 months; radiographic and clinical outcomes were assessed at 3, 6, 12 and 24 months with an additional follow-up at 3 weeks for radiographic assessment. Patients undergoing one- to three-level ACDF with single anterior plate fixation were randomized (1:1 ratio) to receive either cortical allograft or PEEK interbody spacers. Comparing clinical outcomes, no differences in arm or neck pain scores were noted, however there was a statistically significant (< 0.041) improvement in SF-36 PCS scores for the allograft group at all follow-up time points and a tendency towards lower disability scores. Overall, evidence of radiographic fusion was achieved in 87 (91.6%) patients: five (10.2%) and three (6.5%) patients had pseudoarthrosis (p=0.72) in the PEEK and allograft groups, respectively. At 24 months follow-up time, any cervical or segmental alignment restoration achieved with surgery was lost and no statistically significant changes were detected when all levels of surgery were included. Likewise, there were no statistically significant differences between the groups for anterior or posterior body height measurements at the 24 months follow-up. Approximately 20% of patients had anterior and posterior subsidence, all grade 0 regardless of the group assignment. Comparable radiographic outcomes were observed for patients undergoing one- to three-level PEEK vs allograft-assisted ACDF surgeries. There was a tendency for improved clinical outcomes in the allograft patient group.