Background: Sacroiliac joint (SIJ) pain after spinal surgery is a common problem. The objectives of this study were to report the frequency of new-onset SIJ pain after spinal fusion surgery and identify factors associated to the response to injection.
Methods: A total of 200 patients had lumbar or lumbosacral fixation between June 2017 and December 2018. This retrospective study included 41 patients who had sacroiliac joint pain after spinal fusion surgery that did not respond to conservative treatment and therefore underwent injection. All patients were followed after surgery for six months. Study endpoint was the post injection response of low back pain and referred pain was assessed with visual analogue (VAS) , Oswestry Disability Index (ODI) less and more than 3 months and evaluated by Odom's crtiteria.
Results: The mean age was 46.29 ±11.08 years and male presented 53.7%. Thirty-three patients (80.5%) had positive provocative test and 27 patients (65.9%) had severe pre-injection pain with equal pre-injection VAS and ODI scores. There was a significant improvement in VAS and ODI scores post-injection (p < 0.001). Excellent Odom's criteria was achieved in younger patients (p= 0.04), and in patients with moderate pre-injection VAS/ODI score (p < 0.001). Thirty-two patients (78%) had response after three months.
Conclusion: SIJ pain is common after spinal fusion surgery. Good to excellent improvement of pain and disability could be achieved with in 3-6 months post injection. SIJ Injection could be an effective option to improve the outcomes in patients who failed conservative medical management.