Objective:
Thoracolumbar vertebral body fractures are the most common spine injuries. Despite the development of the Thoracolumbar AOSpine Injury Score (TL AOSIS) and Load Sharing Classification (LSC), treatment criteria remain unclear. Consequently, surgical indications and approaches are considered on a case-by-case basis, depending on the patient's age and the presence of concomitant injuries. Additionally, the range of fixation is also considered according to each case. Based on this background, this study compares outcomes of 1above-1below (1A1B) and 2above-2below (2A2B) posterior fusion in 33 patients with LSC scores of 7 or higher.
Subjects and Methods:
Thirty-three patients (20 males and 13 females, mean age 54.1 years, treatment level of Th5-L5, TL AOSIS grades: A2-B2) with LSC scores of 7 or higher underwent posterior fusion for thoracolumbar vertebral fractures. They were classified into 1A1B (Group A) and 2A2B (Group B). Parameters such as age, gender, LSC score, anterior reconstruction presence, pre-and postoperative vertebral kyphosis correction (ΔVK), local kyphosis correction (ΔLK), and vertebral body wall height correction loss were analyzed at 3 months post-surgery using X-ray images. The significance level was set at 0.05.
Results:
Both groups showed no significant differences in gender, LSC score, the presence of anterior reconstruction, ΔVK, VK, and LK correction loss, and vertebral wall height correction loss. However, significant differences were found in age (average 50±19.6 years in Group A vs. 77.2±5.5 years in Group B) and ΔLK (77.3°in Group A vs. 27.7° in Group B). One patient in Group B experienced postoperative implant failure.
Conclusion:
In general, the necessity of anterior reconstruction in patients with LSC scores of 7 or higher is highlighted due to significant vertebral fractures. However, the utility of posterior reconstruction alone has been reported with the advancement of MIS devices like the PPS. As a result, although 2A2B fixation was performed in older patients, no significant difference was observed in postoperative correction loss in either group. This suggests that patients with LSC scores of 7 or higher could be effectively treated within the range of 1A1B fixation.