The incidence of new onset sacroiliac joint pain following lumbar fusion.

BACKGROUND

The sacroiliac joint (SIJ) can be a new source of pain following lumbar fusion. The aim of this study was to identify the incidence of and predisposing factors for new onset SIJ pain following successful lumbar fusion.

METHODS

We review our series of 317 patients who underwent spinal fusion in the past 5 years to identify patients who developed new onset SIJ pain. All patients had a minimum 12 months follow up. Diagnostic criteria for SIJ pain were: New onset pain localised to lower lumbar region and buttocks, ≥2 positive provocative tests of SIJ and pain relief of >70% achieved from SIJ block.

RESULTS

There were 38 patients who developed new SIJ pain following fusion with an overall incidence of 12.0%. The average time to new onset symptoms was 22 months. Of the 38 patients, 57.9% had fusion to sacrum. The incidence of SIJ pain in patients who had fusion extending into sacrum was 12.6% . 11.2% in those who had not. The incidence of SIJ pain was 11.1% with 1-level fusion, 12.0% with 2-level fusion, 12.9% with 3-level fusion and 14.0% with equal or more than 4-level fusion.

CONCLUSIONS

New onset SIJ pain can arise following spinal fusion. We have not found a higher frequency of SIJ pain in patients with fusion extending to sacrum or longer spinal construct.