COMPARISON OF CLINICAL AND RADIOLOGICAL OUTCOMES OF THREE SURGICAL TECHNIQUES IN SCHEUERMANN'S KYPHOSIS

Objective To compare the radiological and clinical outcomes following three different techniques used in the correction of Scheuermann9s kyphosis. Materials and Methods Twenty three patients with comparable preoperative radiographic and physical variables (age, gender, height, weight, body mass index) underwent correction of thoracic kyphotic deformity using three different surgical methods. Group A (n=8) had combined anterior and posterior fusion with instrumentation using morselised rib graft. Group B (n=7) had combined anterior and posterior fusion with instrumentation using titanium interbody cages. Group C (n=8) had posterior segmental pedicle screw fixation only. All groups had posterior apical multi-level chevron osteotomy and posterior instrumentation extending from T2 to L2/3. Preoperative and postoperative curve morphometry studied on plain radiographs included Cobb angle, sagittal vertical axis (SVA), sacral inclination (SI) and lumbar lordosis (LL). Preoperative and postoperative questionnaires including ODI, VAS and SRS-22 were also analysed. Results The average follow-up was 70 months for group A, 66 months for group B and 35 months for group C. For the whole cohort, the preoperative median cobb angle for thoracic Kyphosis was 88.4°, SVA +3.5 centimeters (cms), lumbar lordosis was 66 °, and the median sacral inclination angle was 40°. The average immediate postoperative cobb angle for thoracic kyphosis was 42°, SVA -1.5 cms, lumbar lordosis 45 ° and sacral inclination angle was 30°. At follow-up, the average cobb angle for thoracic kyphosis was 42.0°, SVA +1 cm, lumbar lordosis 42.0 ° and sacral inclination angle was 22.0 °. There was a significant difference between preoperative and postoperative measurements in all three groups, indicating that good correction and satisfaction was achieved. Three patients had distal junctional Kyphosis in early cases. There was no significant difference obtained in the final cobb angle between group A, group B and group C. All three groups retained the postoperative correction with respect to thoracic kyphosis, and changes in ODI and SRS-22 scores were similar in three groups. Conclusion In all groups the SVA became negative following correction and at long-term follow-up it was observed to return towards normal physiological limits. The compensatory lumbar curve reduces and this was associated with a decrease in sacral inclination. This method of compensation, without causing junctional kyphosis, has not previously been reported. We were unable to demonstrate a significant difference between the three groups with regards to the clinical outcome, the degree of initial correction, loss of correction and complications. Therefore, in conclusion, we believe a single stage posterior correction and segmental instrumentation not only provides the same clinical and radiological outcomes, but also reduces blood loss, operative time and hospital stay. Ethics approval: None Interest Statement: None