Віддалені імплантат-асоційовані ускладнення після ізольованої передньої стабілізації при травмах грудо-поперекового переходу: радіологічний та клінічний аналіз

Objective: To evaluate the long-term implant-related complications following anterior-only stabilization of traumatic thoracolumbar injuries and to identify structural and radiological patterns associated with construct failure. Materials and methods: A retrospective multicenter study was conducted at two neurosurgical institutions (Kyiv, Ukraine; Lahore, Pakistan) between 2000 and 2023. Sixteen patients who underwent anterior stabilization at T11–L2 and developed mechanical complications ≥5 years postoperatively were included. Radiographic analysis (CT, X-ray) assessed signs of construct instability, segmental kyphosis (modified Cobb method), global sagittal balance (SVA), and bone mineral density (Hounsfield units, HU). Neurological status was graded using the ASIA scale; pain was assessed via VAS. A complication severity score was developed based on the type of implant failure. Statistical analysis was performed using R version 4.0.5. Results: The most frequent complications were screw-related failures (87.5%), plate migration (68.8%), and cage subsidence/displacement (31.3%). A direct correlation was observed between the severity of structural failure and kyphotic deformity: the median Cobb angles for high-severity cases reached 57°. Global sagittal imbalance (SVA>50 mm) was present in 31.3% of patients, primarily among those with the most severe failures. Neurological decline occurred in 25% of cases, exclusively in the presence of marked kyphosis or implant migration. A bone density < 135 HU was associated with a higher risk of earlier complication onset (HR = 2.83; p = 0.068). Pain intensity showed only a weak correlation with structural deformity. Conclusions: Anterior-only stabilization at the thoracolumbar junction provides effective decompression and anterior column support but carries a risk of delayed mechanical complications, particularly in the absence of posterior reinforcement. The cantilever effect remains a key biomechanical vulnerability. Patients with HU < 135 should be considered at an elevated risk. A tailored surgical strategy, meticulous implant positioning, and long-term radiological surveillance are critical. In cases with poor bone quality or suspected PLC injury, posterior stabilization may offer superior long-term outcomes.