P130. Comparative safety and efficacy of four surgical techniques in three level Anterior Cervical Discectomy and Fusion (ACDF)

Abstract

<h3>BACKGROUND CONTEXT</h3> No consensus exists on the ideal surgical technique for multilevel ACDF, the gold standard treatment for cervical disc disease. Anterior plate (AP) fixation has been traditionally utilized for additional stability but associated complications have led to the increased use of stand-alone (SA) PEEK-anchored cages in recent years. There is a paucity of literature on use of these techniques in 3-level ACDF patients. In order to gain insight into the optimal surgical technique for 3-level ACDF, we conducted a retrospective comparative analysis of the safety and efficacy of the AP, SA and two other common surgical techniques. <h3>PURPOSE</h3> To compare the safety and efficacy of four surgical techniques in patients receiving three-level Anterior Cervical Discectomy and Fusion (ACDF). <h3>STUDY DESIGN/SETTING</h3> A retrospective chart review of patients who underwent primary 3-level ACDF by the two senior authors at two hospitals in Westchester County, NY. <h3>PATIENT SAMPLE</h3> A total of 50 patients who received primary 3-level ACDF by the senior authors between August 2015 and February 2020. <h3>OUTCOME MEASURES</h3> The outcomes investigated in this study include the following: Clinical Success (measured using Odom's criteria score), Safety (complication incidence), Operative (OP) Time, Blood Loss (BL) and Hospital Length of Stay (LOS). <h3>METHODS</h3> Surgical and clinical data for 50 patients who received primary 3-level ACDF by the senior authors between August 2015 and February 2020 was retrospectively analyzed. All patients received a combination of autograft and allograft. Four patient groups were compiled based on surgical technique performed; Anterior Plating with no cage at 3 levels (AP, 24%), Stand-Alone PEEK-anchored cages at 3 levels (SA, 30%), Stand-Alone PEEK-anchored cage at the first level and Anterior Plating with PEEK-anchored cages at the 2 subsequent levels (SAAP, 30%), and Anterior Plating with PEEK-anchored cages at three levels (APC, 16%). Patients were assessed at 5 time points: 1-4 weeks, 5-10 weeks, 3-5.5 months, 6-8 months and 9-12 months. At each time point, patients were evaluated for clinical success (using Odom's Criteria scoring) and safety (complication incidence). Other outcomes investigated include Operative (OP) Time, Blood Loss (BL) and Hospital Length of Stay (LOS). Data analysis was conducted in SPSS 20.0 (SPSS, Inc. Chicago, IL) and included one-way ANOVA, two-tailed t-test, and linear regression analyses. <h3>RESULTS</h3> Patients in the AP group had longer mean OP times (220 min) when compared to patients in the SA (170 min, p=0.04), SAAP (175 min, p=0.009), and APC (167 min, p=0.01) groups. The difference in mean OP time between the AP group and each of the other patient groups were statistically significant (p=0.008). A linear regression analysis showed no significant differences in the mean Odom's criteria score between the four groups (1) over time and (2) at each time point. There were four complications recorded, one per group. The complications were as follows (group in parenthesis): pulmonary embolism (AP), hematoma (SA), adjacent level disease (SAAP) and broken hardware (APC). There were no statistically significant differences between any of the patient groups regarding BL (p = 0.378) and LOS (p = 0.174). The following patient factors were controlled for in all analyses: advanced age (age greater than 65), gender, high BMI (BMI greater than 35), diabetes, osteoporosis, cardiac history (hypertension and/or myocardial infarction), sleep apnea and smoking status. None of these factors were found to have a statistically significant effect on the study outcomes. <h3>CONCLUSIONS</h3> Consistent with the literature, the OP times were longer for 3-level ACDF patients who underwent the AP technique compared to patients who underwent the SA technique. We demonstrated that patients in the AP group also had longer OP times than patients in the SAAP and APC groups. In addition, all four surgical techniques appeared to have analogous safety profiles and clinical success rates. Past studies in the literature examining the AP and SA techniques in 2-level ACDF patients have reported comparable clinical outcomes. Future studies should employ a larger sample size and investigate radiological outcomes such as fusion rate and loss of lordosis. <h3>FDA DEVICE/DRUG STATUS</h3> This abstract does not discuss or include any applicable devices or drugs.