Idiopathic thoracolumbar/lumbar scoliosis treated with anterior correction and interbody fusion with calcium phosphate cement

Abstract

To investigate the clinical outcome and fusion rate in patients with idiopathic thoracolumbar/lumbar scoliosis treated with anterior correction and interbody fusion with calcium phosphate cement. From October 2006 to March 2008, 24 cases undergoing anterior correction and interbody fusion with calcium phosphate cement were enrolled. All of them were female, with an age ranged from 12 to 25 years. The mean Cobb angle of main curve was 46° ± 5° (range, 40° - 56°) before surgery. During operation, the most proximal and distal disc spaces were filled with rib autograft, while the remaining levels were filled with calcium phosphate cement. The interbody fusion rate, coronal correction and sagittal profile reconstruction were evaluated respectively by using χ² test and t test. Interbody fusion was performed in 103 levels, including 48 levels with rib autograft and 55 levels with calcium phosphate cement. The mean follow-up period was 23.8 months (range, 12 - 33 months) in this series. At the follow-up of 6 months, fusion rate was found as 54.2% in the levels filled with rib autograft, while 50.9% in those filled with calcium phosphate cement. Solid fusion of the whole instrumented area was achieved in all cases with a minimum one-year follow-up. No instrumentation-related complications occurred. The correction rate of main curve was on an average of 76% ± 11% after surgery. A significant difference was found between preoperative and immediate postoperative value in terms of the main curve magnitude (46° ± 5° vs. 14° ± 5°, t = -26.95, P < 0.05). The correction loss of the main curve was -5.1° - 10.4° at the final follow-up. The coronal balance and lower instrumented vertebra tilting were significantly improved after operation. The thoracolumbar kyphosis was significantly reduced postoperatively (t = 3.11, P < 0.05). Satisfactory bone fusion and correction maintenance can be achieved in idiopathic thoracolumbar/lumbar scoliosis treated by anterior instrumentation combined with interbody fusion using calcium phosphate cement.