Mid-term efficacy of inferior parietal osteotomy in the treatment of patients with degenerative thoracolumbar kyphosis with apex located at T12

English Keywords:Degenerative spinal kyphosis  Thoracolumbar  Osteotomy  Clinical efficacy

English Abstract:

  【Abstract】 Objectives: To investigate the clinical effect of inferior parietal osteotomy in the treatment of patients with degenerative thoracolumbar kyphosis with apex located at T12. Methods: The clinical and imaging data of 29 patients with thoracolumbar kyphosis treated with posterior correction and fusion as well as single segment pedicle subtraction osteotomy(PSO) at the inferior parietal level in our hospital from January 2017 to December 2021 were retrospectively analyzed. The patients were all female aged 60.6±5.5 years old, and were followed up for 28.1±3.8 months. Radiographic parameters including global kyphosis(GK), thoracic kyphosis(TK), thoracolumbar junctional kyphosis(TJK), lumbar lordosis(LL), sagittal vertical axis(SVA), pelvic incidence(PI), pelvic tilt(PT), sacral slope(SS), T1-pelvic angle(T1PA) were measured in the standing radiographs before and after operation and at the final follow-up. Quality of life of the patients were evaluated by the Scoliosis Research Society-22 questionnaire(SRS-22), the lumbar stiffness disability index(LSDI), the Oswestry disability index(ODI) and the visual analog scale(VAS). Intraoperative neurophysiological monitoring events(IONM), postoperative neurologic damage, and complications were recorded. Results: The sagittal GK was corrected from 63.3°±11.3° preoperatively to 27.3°±8.3° postoperatively(P<0.001), and the correction rate was (56.4±12.4)%. At the final follow-up, the GK was 29.5°±8.4°, and the rate of correction loss was (10.1±14.6)%. TJK was corrected from 52.9°±10.2° preoperatively to 17.0°±3.3° postoperatively(P<0.001), and the correction rate was (67.0±7.8)%. The TJK at the final follow-up was 16.9°±3.0°, showing no significant difference from that after operation(P=0.609). SVA was improved from preoperatively 44.3±34.1mm to postoperatively 20.4±23.6mm(P<0.001), and it was 25.5±24.9mm at the final follow-up, which showed no significant difference compared with that after operation(P=0.086). After surgical treatment, the postoperative quality of life of the patients was significantly improved compared with that before surgery. The scores of SRS-22(pain, image, psychological, activity function), ODI, VAS and LSDI at final follow-up were significantly different from those before surgery(P<0.001). IONM events occurred in 2 patients(6.9%), and none of the patients showed neurologic impairment related complications after surgery. Four patients had proximal junction kyphosis(PJK) during follow-up period. Infection, screw loosening, screw fracture and rod fracture were not identified in the cohort. Conclusions: For patients with degenerative thoracolumbar kyphosis(apical vertebra at T12), PSO performed at one lower level of the apex vertebra not only can achieve satisfactory clinical results, but also improve the safety of the operation and reduce the risk of postoperative complications.