Efficacy analysis of posterior multi-segment Ponte osteotomy and pedicle subtraction osteotomy in treating Scheuermann′s thoracolumbar kyphosis

English Keywords:Scheuermann′s disease  Kyphosis  Ponte osteotomy  Pedicle subtraction osteotomy  Efficacy

English Abstract:

  【Abstract】 Objectives: To compare and analyze the efficacies of posterior multi-segment Ponte osteotomy and pedicle subtraction osteotomy(PSO) in the treatment of Scheuermann′s thoracolumbar kyphosis(STLK). Methods: We retrospectively analyzed the data of patients with STLK(apex below T10) who underwent multi-segment Ponte osteotomy or PSO at our hospital from December 2011 to June 2021, and 18 patients were included with a mean follow-up of 35.83±8.41 months(26-55 months). 10 out of the 18 patients were included in the Ponte group(three-segment osteotomy on average), and the other 8 were include in the PSO group(single-segment osteotomy). Data such as age, gender, body mass index(BMI), apical vertebra, lesion segments, surgical segments, operative time, intraoperative blood loss, postoperative drainage volume, length of hospital stay, follow-up period, and surgical complications of both groups of patients were recorded. The visual analogue scale(VAS) was compared between the two groups before operation, at 1 week post-operation and the final follow-up, the Oswestry disability index(ODI) and Scoliosis Research Society-22(SRS-22) patient questionnaire scores were compared between the two groups before operation and at the final follow-up. Thoracic kyphosis(TK), global kyphosis(GK), GK correction ratio, GK correction loss ratio, T1 pelvic angle(TPA), T1-L1 pelvic angle(TLPA) and lumbar lordosis(LL), pelvic tilt(PT), sacral slope(SS), pelvic incidence(PI), PI-LL and sagittal vertical axis(SVA) were measured and compared between the two groups before operation, at 1 week after operation and the final follow-up. Results: All the patients were successfully operated, with superficial surgical site infection occurred in 2 cases in Ponte group and 1 case in PSO group, and no other surgical complications. There were no statistically differences between the two groups in age, gender, BMI, apical vertebra, lesion segments, surgical segments and follow-up time(P>0.05); However, the operative time, intraoperative blood loss, and postoperative drainage were less and length of hospital stay was shorter in the Ponte group than those in the PSO group(P<0.05). The VAS significantly improved in both groups at postoperative 1 week and final follow-up than preoperation(P<0.05), while there was no significant difference between the two groups at each time points(P＞0.05). The ODI and SRS-22 scores were significantly improved at final follow-up in both groups compared with preoperation(P<0.05), and the ODI was lower while the functional status and self-image scores in the SRS-22 were higher in Ponte group than PSO group(P<0.05). The postoperative TK, GK, TPA, TLPA, LL and SS were significantly lower than those preoperatively in both groups(P<0.05), which all significantly increased at the final follow-up compared with those at postoperative 1 week(P<0.05); the postoperative PT, PI and PI-LL were significantly higher than those before operation in both groups, which were lower at the final follow-up compared with those at postoperative 1 week(P<0.05). There was no statistical difference in SVA before and after surgery in both groups(P>0.05). Correction loss occurred in both groups after operation, with an average GK correction loss ratio of (4.3±1.3)% in Ponte group and (4.9±2.4)% in PSO group. There was no statistical difference between groups for all imaging parameters at different time points(P>0.05). Conclusions: For STLK patients, both posterior multi-segment Ponte osteotomy and PSO with internal fixation can achieve excellent kyphosis correction; and multi-segment Ponte osteotomy is less in operative time, intraoperative blood loss, and postoperative drainage, shorter in length of hospital stay, and better in midterm efficacy with preferable ODI and SRS-22 scores improvement than PSO.