CT classification at extension and its significance for stage Ⅲ Kümmell′s disease

English Keywords:Kümmell′s diease  Subtypes  CT reconstruction image on extension position  Percutaneous vertebral augmentation  Osteotomy and deformity correction

English Abstract:

  【Abstract】 Objectives: To investigate the chlinical value of CT classification at extension position and its significance for stage Ⅲ Kümmell′s disease. Methods: 11 cases of stage Ⅲ Kümmell′s disease between January 2008 and September 2010 were reviewed retrospectively. There were 2 males and 9 females with the average age of 71.4 years(range, 54-87 years). Single level was involved in 10 cases including 5 T12, 1 L1, 3 L2 and 1 L4; two levels was involved in 1 case(T11, L1). Based on the reduction of diseased vertebral collapse over 50% or not and secondary vertebral canal stenosis removal or not on CT scan at extension position, all cases were classified into reducible type(type A, reduction ≥50%) and irreducible type(type B, reduction ＜50%). In the group of type A, according to Denis classification, cases were divided into two subtypes: stable type(A1, with the rate of anteroposterior diameter of fractured body/anteroposterior diameter of vertebral body ≥50%) and unstable type(A2, with that rate ＜50%). Cases with type A1 experienced vertebral augmentation at extension position; cases with type A2 underwent internal fixation, fusion and vertebral augmentation at extension position; cases with type B underwent posterior osteotomy and fusion. The clinical outcomes were evaluated by visual analog scale(VAS), kyphosis angle(Cobb′s), and ODI at preoperative, 3 months and the final follow-up respectively. Furthermore, all perioperative complications were recorded. Results: There were 5 cases with type A1, 3 type A2 and 3 type B. All of the patients were followed up for an average of 18 months(range, 6-33 months). 2 cases experiencing vertebral augmentation(1 A1 and 1 A2) were noted bone cement leakage, but no symptom was noted. 1 case of type B was complicated with severe hypertension, right heart failure and atrial fibrillation after operation, and was alleviated by active intervention. The kyphosis Cobb angles, VAS scores, ODI at 3 months and final follow-up improved significantly. Conclusions: Based on CT reconstruction at extension position, stage Ⅲ Kümmell′s disease can be divided into three types which are type A1, A2 and B respectively, which is meaningful for determining individualized management.