Analysis of factors associated with the failure of treatment in thoracolumbar burst fractures treated with short-segment posterior spinal fixation

Abstract

Background: The treatment of thoracolumbar burst fractures continues to pose challenges. Although short-segment posterior spinal fixation (SSPSF) has shown satisfactory clinical outcomes, it is accompanied by a relatively high rate of treatment failure. This study aimed to assess factors associated with treatment failure in thoracolumbar burst fractures treated with SSPSF.

Methods: The clinical data of 241 consecutive patients with a traumatic thoracolumbar burst fracture who underwent SSPSF at our center between Apr 2016 and Apr 2021 were retrospectively reviewed. Patients were divided into two groups (failure of the treatment group and non-failure of the treatment group). We compared potential risk factors for the failure of treatment including age, gender, body mass index, smoking, diabetes, vertebral body compression rate, use of crosslinks, percentage of anterior height compression, presence of index level instrumentation, Cobb angle, interpedicular distance (IPD), canal compromise, Load Sharing Classification (LSC) score, use of posterolateral fusion, and pain intensity between the two groups.

Results: A sum of 137 (56.8%) males and 104 (43.2%) females were enrolled where the mean age and follow-up of the participants were 48.34 ± 10.23 years and 18.67 ± 5.23 months, respectively. Treatment failure was observed in 34 cases (14.1%). The results of the binary logistic regression analysis revealed that the lack of index level instrumentation (OR 2.21; 95% CI 1.78-3.04; P = 0.014), LSC score (odds ratio [OR] 2.64; 95% confidence interval [95% CI], 1.34-3.77; P = 0.007), and IPD (OR 1.77; 95% CI 1.51-2.67; P = 0.023) were independently associated with a higher rate of failure of treatment.

Conclusions: The findings of this study revealed that increased rates of treatment failure in thoracolumbar burst fractures treated with SSPSF were associated with factors such as the absence of index level instrumentation, higher LSC scores, and larger IPD. These findings could be helpful in the proper management of patients with unstable thoracolumbar burst fractures.

Keywords: Failure of treatment; Interpedicular distance; Load sharing classification; Short-segment posterior spinal fixation; Thoracolumbar burst fractures.

Fig. 1

Cobb angle was measured as the angle between the superior endplate of the vertebra above the fracture and the inferior endplate of the vertebra below the fracture. Vertebral body compression rate (VBCR) and percentage of anterior height compression were calculated as follows: VBCR = AVH/PVH × 100%. PAHC = AVH/[(AVH* + AVH**)/2] × 100%. AVH: Anterior vertebral height of the fractured vertebra. AVH*: Anterior vertebral height of a vertebra above the fracture. AVH**: Anterior vertebral height of a vertebra below the fracture. PVH: posterior vertebral height of fractured vertebra

Fig. 2

The interpedicular distance (IPD) was calculated by comparing the widening between the pedicles of the fractured vertebrae with the mean of similar values obtained from levels above and below them; IPD = [2D − (D* + D**) / (D* + D**)] × 100%