The surgical treatment of Andersson lesions associated with ankylosing spondylitis

Eight men with Andersson lesions associated with ankylosing spondylitis who underwent surgical treatment were reviewed for this study. Eight Andersson lesions were found in the 8 patients, and all presented as pseudoarthrosis. Including a patient with obvious vertebral body destruction, no obvious local kyphosis was observed. Spinal cord compression and neural deficit were observed in 1 patient. Without established instructions for the surgical treatment of Andersson lesions, we alternated the surgical technique for each patient. Therefore, 5 patients, including the patient with obvious anterior destruction requiring reconstruction, underwent surgical treatment with lesion curettage and anterior bone graft and fusion; 3 other patients underwent surgical treatment without lesion curettage and anterior bone graft. All surgeries were performed from a posterior approach. Posterolateral autograft was supplemented to posterior instrumentation with or without anterior bone graft.All 8 patients experienced pain relief immediately postoperatively. No evidence of non-union was observed on radiographs at the level of pseudoarthrosis at final follow-up, and no neural and infectious complications were observed. Based on these results, surgical treatment with only posterior instrumentation supplemented by posterolateral autograft was effective for patients with Andersson lesions without obvious vertebral body destruction requiring reconstruction. Anterior lesion curettage and bone graft were not necessary. Solid immobilization, achieved by posterior instrumentation, should be the focus of the treatment of Andersson lesions with ankylosing spondylitis.