Postoperative Ketorolac Does Not Predispose to Pseudoarthrosis Following Posterior Spinal Fusion and Instrumentation for Adolescent Idiopathic Scoliosis

Abstract

A retrospective review comparing patients who had postoperative ketorolac and those who did not following posterior spinal fusion and instrumentation (PSFI) for adolescent idiopathic scoliosis (AIS). To analyze the effect of postoperative ketorolac on the incidence of pseudoarthrosis in postoperative AIS patients. Ketorolac (Toradol, Roche Laboratories, Nutley, NJ) is a nonsteroidal antiinflammatory drug that is an effective adjunct to manage postoperative pain. It has been previously demonstrated to inhibit spinal fusion in adult patients undergoing a L4 to sacral fusion. To our knowledge, there are no large studies analyzing this effect following PSFI for AIS. An IRB-approved retrospective medical record review was performed from 1994 to 2000 of patients undergoing a PSFI for AIS at a single institution. Segmental spinal instrumentation (Texas Scottish Rite Hospital) and iliac crest bone graft were used in both groups. Demographic and operative data were recorded. Patients were divided into those who had postoperative ketorolac (K group) and those who did not (NK group). Patients who had a surgically confirmed pseudoarthrosis were identified and the K group and NK group were statistically compared. There were 161 patients in the NK group and 158 in the K group. There were no differences with respect to age (14.4 vs. 14.2 years), gender (83.9% vs. 84.8% females), levels fused (9.8 vs. 9.7), or preoperative curve magnitude (57.9 degrees vs. 58.9 degrees ). In the K group, the number of doses of ketorolac administered was 6.7 for an average of 26.7 mg for a duration of 46 hours after surgery. Patients in the K group were more likely to have Motrin (average 5.8 doses) compared with the NK group (average 0.7 doses) (P < 0.01). No patient in the K group had a history of cigarette smoking compared with 2 patients in the NK group, both of whom went on to solid arthrodesis. The overall incidence of pseudoarthrosis was 2.5% for all patients. There was no difference in the incidence of pseudoarthrosis comparing the K (1.9%) and the NK group (3.1%)(P = 0.7). When the single rod posterior implants were excluded, there was no difference between the K (0.7%) and NK groups (1.8%) (P = 0.58). Ketorolac does not increase the incidence of developing a pseudoarthrosis when used as an adjunct for postoperative analgesia following a PSFI for AIS using segmental spinal instrumentation and iliac crest bone graft. The differences seen here compared with adults may be due to the greater healing potential in these young patients. We recommend utilization of ketorolac after surgery to supplement pain management when necessary.