Design and clinical application of a new extracorporeal reduction device for percutaneous pedicle screw fixation in treatment of thoracolumbar fractures

Abstract

To design a new extracorporeal reduction device for percutaneous pedicle screw fixation of thoracolumbar fractures (short for "new reduction device"), and to evaluate its effectiveness. According to the mechanism of thoracolumbar fractures and biomechanics characteristic of reduction, a new reduction device was designed and used in a combination with long U-shaped hollow pedicle screw system. Between January 2014 and January 2016, 36 patients (group A) with single segment thoracolumbar fracture without neurological complications underwent percutaneous pedicle screw fixation, and the clinical data were compared with those of another 39 patients (group B) with thoracolumbar fracture underwent traditional open pedicle screw fixation. There was no significant difference in gender, age, cause of injury, classification of fractures, segments of fractures, injury to operation interval, height percentage of injury vertebrae, and kyphotic angle between 2 groups ( P>0.05). The 2 groups were compared in terms of operation time, length of incision, intraoperative blood loss, drainage volume, visual analogue scale (VAS) at postoperative 24 hours, fluoroscopy frequency, ambulation time, height percentage of injury vertebrae, kyphotic angle and correction. Group A was significantly better than group B in the operation time, length of incision, intraoperative blood loss, drainage volume, VAS score at postoperative 24 hours, and ambulation time ( P<0.05). However, fluoroscopy frequency of group B was significantly less than that of group A ( P<0.05). All patients were followed up 11.2 months on average (range, 7-15 months). There was no intraoperative and postoperative complications of iatrogenic nerve injury, infection, breakage of internal fixation. Mild pulling-out of pedicle screws occurred in 1 case of group A during operation. The kyphotic angle and height percentage of the fractured vertebral body were significantly improved at 3 days after operation when compared with preoperative ones ( P<0.05), but no significant difference was found between 2 groups at 3 days after operation ( P>0.05). Minimally invasive extracorporeal reduction device for percutaneous pedicle screw fixation is an effective and safe treatment of thoracic vertebrae and lumbar vertebrae fractures, because of little trauma, less bleeding, and quicker recovery.