Clinical Efficacy and Safety of Controlled Distraction-Compression Technique Using Expandable Titanium Cage in Correction of Posttraumatic Kyphosis

Abstract

Objective : To investigate the clinical efficacy and safety of the controlled distraction-compression technique using an expandable titanium cage (ETC) in posttraumatic kyphosis (PTK). Methods : We retrospectively studied and collected data on 20 patients with PTK. From January 2014 to December 2017, the controlled distraction-compression technique using ETC was consecutively performed in 20 patients with PTK of the thoracolumbar zone (range, 36-82 years). Among them, nine were males and 11 were females and the mean age was 61.5 years. The patients were followed regularly at 1, 3, 6, and 12 months, and the last follow-up was more than 2 years after surgery. Results : The mean follow-up period was 27.3 +/- 7.3 months (range, 14-48). The average operation time was 286.8 +/- 33.1 minutes (range, 225-365). The preoperative regional kyphotic angle (RKA) ranged from 35.6 degrees to 70.6 degrees with an average of 47.5 degrees +/- 8.1 degrees. The immediate postoperative mean RKA was 5.9 degrees +/- 3.8 degrees (86.2% correction rate, p=0.000), and at the last follow-up more than 2 years later, the mean RKA was 9.2 degrees +/- 4.9 degrees (80.2% correction rate, p=0.000). The preoperative mean thoracolumbar kyphosis was 49.1 degrees +/- 9.2 degrees and was corrected to an average of 8.8 degrees +/- 5.3 degrees immediately after surgery (p=0.000). At the last follow-up, a correction of 11.9 degrees +/- 6.3 degrees was obtained (p=0.000). The preoperative mean back visual analog scale (VAS) score was 7.9 +/- 0.8 and at the last follow-up, the VAS score was improved to a mean of 2.3 +/- 1.0 with a 70.9% correction rate (p=0.000). The preoperative mean Oswestry disability index (ODI) score was 32.3 +/- 6.9 (64.6%) and the last follow-up ODI score was improved to a mean of 6.85 +/- 2.9 (3.7%) with a 78.8% correction rate (p=0.000). The overall complication was 15%, with two of distal junctional fractures and one of proximal junctional kyphosis and screw loosening. However, there were no complications directly related to the operation. Conclusion : Posterior vertebral column resection through the controlled distraction-compression technique using ETC showed safe and good results in terms of complications, and clinical and radiologic outcomes in PTK. However, to further evaluate the efficacy of this surgical procedure, more patients need long-term follow-up and there is a need to apply it to other diseases.