Influence of intervertebral disc injury on surgical outcome of thoracolumbar fractures after percutaneous pedicle screw fixation

Objective To analyze the influence of intervertebral disc injuries on the surgical outcome of percutaneous pedicle screw fixation for thoracolumbar fractures. Methods Clinical data about 43 patients with thoracolumbar fractures who underwent percutaneous pedicle screw fixation in our department from January 2015 to May 2018 were retrospectively analyzed.According to the Sander's classification,the patients were divided into disc injury group （n=24） and non-injury group （n=19）.The Cobb angle （CA）,vertebral body angle （VBA） and intervertebral angle （IVA） were calculated and compared between the two groups before and after surgery. Results There was no significant difference in terms of gender,age,vertebral segment involved between the two groups （all P>0.05）.Statistically significant improvements were observed in CA,VBA and IVA after surgery (P_time<0.05) in both the two groups,but no significant difference was found in these radiologic outcomes between the two groups (P_intergroup>0.05),except IVA at last visit （1.000.00,1.00° vs 0.00-1.00,1.00°,P=0.012）.Correction loss was found in CA,VBA,and IVA in both groups,and injury group had significant higher loss in CA （4.63±4.29° vs 2.53±1.93°） and IVA （2.501.00,3.75° vs 0.000.00,1.00°）(P<0.05,respectively). Conclusion Intervertebral disc injury may cause more serious correction loss in patients with thoracolumbar fractures after percutaneous pedicle screw fixation.