Effects of modified SRS-Schwab grade Ⅳ osteotomy on digestive function in the treatment of kyphosis after old thoracolumbar fractures

English Keywords:Old thoracolumbar fractures  Kyphosis  Osteotomy  Digestive function

English Abstract:

  【Abstract】 Objectives: To investigate the changes of digestive function after the treatment of kyphosis secondary to old thoracolumbar fractures with modified SRS-Schwab grade Ⅳ osteotomy and analyze the related influencing factors. Methods: The clinical data of 36 patients with kyphosis after old thoracolumbar fractures who underwent posterior modified SRS-Schwab grade Ⅳ osteotomy in our hospital from January 2018 to December 2020 were retrospectively analyzed, including 16 males and 20 females, aged 50-75 years old(62.19±6.79 years old）. The patients were followed up for 12-18 months, with an average of 13.6±2.1 months. The functional digestive disorders quality of life(FDDQL) questionnaire and gastrointestinal symptom rating scale(GSRS) were used to evaluate the digestive function of patients, and the differences between before operation and at the final follow-up(dFDDQL, dGSRS) were calculated respectively; The visual analogue scale(VAS) and Oswestry disability index(ODI) were adopted to assess the pain and disability, and difference between before operation and at the final follow-up(dVAS, dODI) were calculated respectively; The focal kyphosis angle(FK) was measured on standing full-length lateral radiograph of the spine before surgery and at final follow-up, and its correction rate was figured. And the projected acreage of the sagittal plane of the abdomen on the full-length lateral radiograph of spine was employed to reflect the abdominal volume, which was measured before operation and at final follow-up, and the difference between was counted. Paired t test was adopted to analyze the respective differences of the above indicators between preoperation and final follow-up. Pearson correlation was used to analyze the correlations between kyphosis correction rate and difference of abdominal sagittal plane area on standing full-length lateral X-ray films and dFDDQL and dGSRS. Results: All patients completed the operation successfully without serious surgical complications. The final follow-up FDDQL score of digestive function increased from(73.72±5.24)% before operation to (86.02±5.49)%(P＜0.001), and the GSRS score decreased from the preoperative 33.94±2.81 to 21.44±3.19(P<0.001); the final follow-up VAS score of low back pain decreased from 7.47±1.02 before operation to 1.22±0.54(P<0.001), and the ODI decreased from (79.74±4.89)% before operation to (20.09±5.61)%(P<0.001); the final follow-up FK decreased from the preoperative 44.01°±7.59° to 7.98°±1.68°(P<0.001), and the projected acreage of the sagittal plane of abdomen on the standing full-length lateral X-ray increased from 152.56±24.87cm2 before operation to 217.24±26.08cm2(P＜0.001). Pearson correlation analysis showed that the dFDDQL score was positively correlated with the correction rate of kyphosis and the difference in the projected acreage of the abdomen on X-ray films before and after surgery(r=0.542, P=0.001; r=0.738, P=0.001); the dGSRS score was positively correlated with the correction rate of kyphosis and the difference in the projected acreage of the abdomen on X-ray films before and after surgery(r=0.623, P<0.001; r=0.772, P<0.001). Conclusions: The modified SRS-Schwab grade Ⅳ osteotomy can safely and effectively correct kyphosis secondary to old thoracolumbar fractures, improve the disordered digestive function by increasing the volume of the abdominal cavity and reducing gastrointestinal entrapment.