Sacroiliac joint arthrodesis for chronic sacroiliac joint pain: an anterior approach and clinical outcomes with a minimum 5-year follow-up.

OBJECTIVE The authors evaluated the outcomes of sacroiliac joint (SIJ) arthrodesis via an original anterior approach to the upper anterior surface of the SIJ in patients with a minimum of 5 years' follow-up. METHODS The authors performed anterior SIJ arthrodesis in 45 patients between 2001 and 2015. Of these patients, 27 (11 men and 16 women; mean age at surgery 49 [24-86] years) were followed up for a minimum of 5 years (average 113 months, range 61-157 months). In the 14 patients in the earlier period of this study, the authors used an anterior approach to expose the SIJ by separating the iliac muscle from the iliac bone and performed internal fixation. In the 13 patients later in the study, the authors changed to a pararectal approach, which involved an incision along the lateral border of the rectus abdominal muscle. Then, extraperitoneally, the upper anterior surface of the SIJ was exposed between the psoas major muscle and the iliac muscle. RESULTS Among the 27 patients, 21 had unilateral anterior arthrodesis alone, 4 required additional posterior arthrodesis, and 2 required pelvic ring arthrodesis because of later pain on the opposite side. In the 21 patients with a unilateral anterior arthrodesis, outcome according to the modified Macnab criteria was excellent in 7, good in 11, and fair in 3. Outcomes were excellent, good, fair, and poor in 1 patient each among the 4 with additional posterior fusion. Outcomes were good and poor for 1 patient each among those with pelvic ring arthrodesis. All 27 patients demonstrated bone union of the SIJ on CT. Lateral femoral cutaneous neuralgia developed in 7 of the 27 patients; 6 patients had undergone the initial anterior method and 1 the later method. CONCLUSIONS Anterior SIJ arthrodesis was effective in most patients with severe SIJ pain resistant to conservative therapy. This approach has the advantage of direct curettage and bone graft into the wide area of the SIJ, which result in good bone union. In particular, the authors' current pararectal approach could decrease the potential risk of lateral cutaneous injury.