One-stage posterior grade 4 osteotomy and bone graft fusion at pseudarthrosis for the treatment of kyphotic deformity with Andersson lesions in ankylosing spondylitis

Effects of Andersson lesion treatment in ankylosing spondylitis: A medical record review study focused on medium‐ to long‐term outcomes

“…In 1972, Cawley et al 1 reviewed the literature and concluded that AL is a delayed complication of AS that manifests as a localized lesion in the vertebral rim that can cause spinal pseudarthrosis and aggravate kyphotic deformity, sagittal imbalance, and pain. As reported in several previous studies, 6,19,22,23 AL most commonly occurs in middle‐aged males (63%‐86%) who experience long‐term progression from a slight fracture or inflammatory reaction to severe erosion. The etiology of AL has yet to be clearly demonstrated.…”

“…[16][17]19,24 Chang et al 25 in AS in relation to JOA recovery rate. 11,23,26 The role of laboratory tests in patients with AL is also controversial. Both ESR and CRP levels may be elevated in patients with AL and may be involved in the clinical disease activity of AL.…”

“…Thus, our study supports this opinion. However, there are still disputes regarding the prognostic factors, and only a few previous studies have reported the medium‐ to long‐term outcomes of AL treatment in AS in relation to JOA recovery rate 11,23,26 . The role of laboratory tests in patients with AL is also controversial.…”

“…Although numerous surgical techniques have been advocated, including instrumented and noninstrumented stabilization through anterior, posterior or combined approaches, the main argument is focused on the necessity of bone grafting and fusion. Bone grafting and fusion are generally accepted as an optimal surgical procedure to treat AL in AS patients and can achieve satisfactory correction of local kyphosis and good safety 21,23,25,26 . In 2006, Chang et al 25 reported that bone grafting was not necessary because of the excellent higher fusion ability of AS patients.…”

“…In 1972, Cawley et al1 reviewed the literature and concluded that AL is a delayed complication of AS that manifests as a localized lesion in the vertebral rim that can cause spinal pseudarthrosis and aggravate kyphotic deformity, sagittal imbalance, and pain. As reported in several previous studies,6,19,22,23 AL most commonly occurs in middle-aged males (63%-86%) who experience long-term progression from a slight fracture or F I G U R E 2 A 55-y-old male patient with ankylosing spondylitis (AS) complicated by Andersson legion (AL) at the level of T11-T12 is presented. Preoperative lateral (A) and anteroposterior (B) plain radiographs of the thoracic region demonstrate the presence of advanced features of ankyloses and spinal lesions with sclerosed irregular margins (white arrow).…”