Abstract
Scoliosis surgery has moved towards all posterior correction, as modern implants are perceived to be powerful enough to overcome stiffer and more severe curves. However, shortening of the anterior spinal column remains most effective in creating thoracic kyphosis, and may still have a role in correcting both coronal and sagittal deformities. Furthermore, anterior correction of lumbar and thoracolumbar curves can theoretically reduce the distal fusion level, and may have significant impact on patients' post-operative function.
A single surgeon series of 62 patients with idiopathic scoliosis were examined retrospectively. Radiographs and operation notes were examined by 2 spinal surgeons, sagittal and coronal parameters were measured before and after the operation. The patients were divided into 4 groups: 16 anterior and posterior fusions (AP), 16 anterior thoracolumbar fusions (A), 5 anterior thoracic releases and posterior fusions (AR), and 25 posterior fusions only (P).
The mean age was 15.3 (range 10 – 20). The mean main thoracic Cobb angle pre-operatively was: 54° (AP), 43° (A), 63° (AR), and 50° (P). The mean thoracolumbar Cobb angle was: 55° (AP) and 51° (A). There was no significant difference in lumbar lordosis.
The mean post-operative main thoracic Cobb angle was: 9° (AP), 13° (A), 9° (AR) and 15° (P). There was significant difference between AR and P groups. The mean post-operative thoracolumbar Cobb angle was: 8° (AP) and 6° for (A). There was a significant difference in the post-operative thoracic kyphosis between AP (mean 14°), A (mean 38°), AR (mean 19°) and P (mean 14°). Overall, the lumbar lordosis for all 4 groups reduced from a mean of 67° to 50°, with no significant difference between the groups.
The distal level of fusion for A and AP groups were L3 for all cases, whereas 2 cases had to extend to L4 in the P group.
Anterior release improved both coronal and sagittal correction when compared to posterior only surgery, however it is of unknown clinical significance. Anterior thoracolumbar fusion with or without posterior spinal fusion appeared to produce adequate coronal correction if fused to L3. No difference was found between all groups in post-operative lumbar lordosis.
