Analysis of reason and strategy for the failure of posterior pedicle screw short-segment internal fixation on thoracolumbar fractures

Objective:To analyze the reason and strategy for failure of posterior pedicle screw short-segment internal fixation on thoracolumbar fractures. Methods:From March 2008 to December 2010,the clinical data of 18 patients with thoracolumbar fracture failed in posterior pedicle screw short-segment internal fixation were retrospectively analyzed. There were 11 males and 7 females with an average age of 37.2 years (ranged,19 to 63). The time from the first operation to complication occurrence was from 6 to 44 months with an average of 14.3 months. Of them,fusion failure was in 7 cases (combined with screw breakage in 4 cases),the progressive neuro-dysfunction was in 5 cases,the progressive lumbodorsal pain was in 6 cases. All 18 patients with kyphosis were treated with anterior internal fixation remaining posterior fixation (9 cases) and anterior internal fixation after posterior fixation removal (9 cases). Results:All the patients were followed up from 18 to 50 months with an average of 30.5 months. No internal fixation loosening and breakage were found,moreover,X-ray and lamellar CT showed bone healing well. Preoperative,postoperative at 3 months and at final follow-up,ODI score was respectively 31.6±5.1,8.6±5.7,8.3±3.2;VAS score was respectively 7.2±2.3,2.3±0.7,2.1±1.1; kyphosis angle was respectively (-21.2±7.8)°,(-5.3±6.8)°,(-5.8±7.8)°. Compared with preoperative data,above-listed items had obviously ameliorated(P0.05). Conclusion:Treatment of thoracolumbar fracture with posterior pedicle screw short-segment internal fixation may result in the complications such as bone nonunion,internal fixation breakage and progressive kyphosis. Anterior reconstruction may be a good strategy for the failure of posterior operation.