Whether a combined anteroposterior fusion or a posterior-only fusion is more effective in the management of patients with Scheuermann’s kyphosis remains controversial. The aim of this study was to compare the radiological and clinical outcomes of these surgical approaches, and to evaluate the postoperative complications with the hypothesis that proximal junctional kyphosis would be more common in one-stage posterior-only fusion. A retrospective review of patients treated surgically for Scheuermann’s kyphosis between 2006 and 2014 was performed. A total of 62 patients were identified, with 31 in each group. Parameters were compared to evaluate postoperative outcomes using chi-squared tests, independent-samples Aims
Methods
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.
There is a wide range of reports on the prevalence of neurological injuries during scoliosis surgery, however this should depend on the subtypes and severity of the deformity. Furthermore, anterior versus posterior corrections pose different stresses to the spine, further quantifications of neurological risks are presented. Neuromonitoring data was prospectively entered, and the database between 2006 and 2012 was interrogated. All deformity cases under the age of 21 were included. Tumour, fracture, infection and revision cases were excluded. All “red alerts” were identified and detailed examinations of the neuromonitoring records, clinical notes and radiographs were made. Diagnosis, deformity severity and operative details were recorded. 2290 deformity operations were performed: 2068 scoliosis (1636 idiopathic, 204 neuromuscular, 216 syndromic, and 12 others), 89 kyphosis, 54 growing rod procedures, and 80 operations for hemivertebra. 696 anterior and 1363 posterior operations were performed for scoliosis (8 not recorded), and 38 anterior and 51 posterior kyphosis correction. 67 “red alerts” were identified, there were 14 transient and 6 permanent neurological injuries. 62 were during posterior stage (24 idiopathic, 21 neuromuscular, 15 syndromic (2 kyphosis), 1 growing rod procedure, 1 haemivertebra), and 5 were during anterior stage (4 idiopathic scoliosis and 1 syndromic kyphosis). Average Cobb angle was 88°. 1 permanent injuries were during correction for kyphosis, and 5 were for scoliosis (4 syndromic, 1 neuromuscular, and 1 anterior idiopathic). Common reactions after “red alerts” were surgical pause with anaesthetic interventions (n=39) and the Stagnara wake-up test (n=22). Metalwork was partially removed in 20, revised in 12 and completely removed in 9. 13 procedures were abandoned. The overall risk of permanent neurological injuries was 0.2%, the highest risk groups were posterior corrections for kyphosis and scoliosis associated with a syndrome. 4% of all posterior deformity corrections had “red alerts”, and 0.3% resulted in permanent injuries; compared to 0.6% “red alerts” and 0.3% permanent injuries for anterior surgery. The overall risk for idiopathic scoliosis was 0.06%.
