Efficacy of pedicle subtraction osteotomy combined with long segment fixation in treating thoracolumbar kyphosis secondary to percutaneous vertebroplasty for osteoporotic vertebral compression fractures

English Keywords:Vertebral compression fracture  Osteoporosis  Kyphosis  Vertebroplasty  Osteotomy

English Abstract:

  【Abstract】 Objectives: To investigate the clinical efficacy of posterior pedicle subtraction osteotomy(PSO) plus long segment fixation for thoracolumbar kyphosis secondary to percutaneous vertebroplasty(PVP). Methods: A retrospective case series study was conducted on the clinical data of 12 patients with thoracolumbar kyphosis secondary to PVP treated in our hospital from January 2017 to December 2022. There were 4 males and 8 females, aged 63-81 years(71.1±5.1 years). Injured segment: one case at T11, two cases at T12, four cases at L1, and five cases at L2. According to the American Spinal Injury Association(ASIA) classification, the spinal injuries were rated as grade C in two patients, grade D in nine and grade E in one. All the patients underwent PSO combined with long segment fixation. The operative time and intraoperative blood loss were recorded. All the patients were followed up for 17-36 months(26.6±5.1 months). The Cobb angle of injured vertebra, thoracolumbar kyphosis(TLK) angle and sagittal vertical axis(SVA) were measured on the standing full-spine radiographs of spine before operation, at one week after operation, and at final follow-up. Visual analogue scale(VAS) score, and Oswestry disability index(ODI) were recorded to evaluate the pain and improvement in function. ASIA grade and fusion status at final follow-up, and complications were recorded. Results: All operations were successfully completed. The operative time was 187-275min(221.4±30.5min), and the intraoperative blood loss was 425-900mL(540.8±125.7mL). One case of dural tear was complicated with cerebrospinal fluid leakage occurred during operation, and the incision healed in one stage after suturing; One other patient developed residual lower back pain after surgery, which improved after targeted therapy with a herbal formula for promoting blood circulation and rehabilitation. The kyphotic Cobb angle of the injured vertebra, TLK, SVA, VAS score and ODI at 1 week and final follow-up significantly improved versus preoperative values(P<0.05). Compared with 1 week postoperatively, SVA at final follow-up significantly increased(P<0.05), while VAS score and ODI significantly decreased(P<0.05). In contrast, the final follow-up kyphotic Cobb angle of the injured vertebra and TLK showed no significant changes from the values at 1 week after operation(P>0.05). ASIA grades at final follow-up were significantly improved(P<0.05), with 1 patient of grade D and 11 patients of grade E. During the final follow-up, all 12 patients achieved fusion, with 11 rated as Bridwell grade Ⅰ and 1 as grade Ⅱ. Furthermore, there was no radiographic evidence of instrumentation loosening or pseudarthrosis. Conclusions: Posterior PSO plus long segment fixation can significantly reduce back pain and promote daily activities and neurological functional recovery in treating thoracolumbar kyphosis secondary to PVP, which can correct the deformity remarkably with durable orthopedic outcome.