Does Perioperative Use of Ketorolac for Pain Control Really Inhibit Spinal Fusion?

Methods: A retrospective review of over 300 patients who underwent posterolateral lumbar spine fusion with instrumentation was performed. Of these, approximately 200 patients received Toradol for pain relief after surgery, whereas 100 did not. A detailed comparison is made with a previous index study, which concluded that postoperative use of ketorolac was detrimental to spinal fusion rates. What were perceived to be significant weaknesses of the previous landmark study were eliminated in this study design. A single surgeon performed all of the surgeries that used Toradol for postoperative analgesia. The same surgeon also operated on almost all of the patients that did not receive Toradol postoperatively. Every single patient was a non-smoker, or had quit for at least five years. Every single patient in the Toradol group got the same dose and duration of Toradol (30 mg intravenously every 6 hours for 48 hours), regardless of pain level. The two groups were demographically equivalent. Results of the two groups were compared with a minimum of 24 months of follow-up.

Results: The results indicate that there is no significant adverse effect on spinal fusion with early post-operative use of Toradol for pain relief. Preliminary data suggests an approximately 6% nonunion rate for the Toradol group vs. a 7% nonunion rate for the non-Toradol group (P > 0.05).

Discussion: The findings in this study are in stark contradistinction with the previous landmark study on this topic. However this study design has some key improvements. The patients studied belong almost entirely to one surgeon. None of them were smokers, which was a significant confounding variable in the previous study (approximately one half of the patients were smokers). In this study every patient in the Toradol group received the same dose and duration of Toradol - it was not given as an "as needed" medication - which would selectively have given more Toradol to patients with more pain (and perhaps more susceptibility to pseudarthrosis). It has been proven in the literature that Toradol is a very effective post-operative analgesic. However, recent studies have suggested that its use may inhibit spinal fusion, significantly decreasing its popularity amongst surgeons. Here we have shown that in a well-controlled study with comparable demographics, adequate power, administration of Toradol in equal doses, and with smoking eliminated as a confounding variable short-term postoperative use of Toradol for analgesia cannot be shown to increase nonunion rates in spine surgery. In animal studies, prolonged use of NSAIDs has inhibited healing and bone fusion, but limited post-operative use for pain control in humans may have no significant long-term effect.