Factors affecting the formation of bone block in patients with isthmic spondylolisthesis

Objective. To analyze significance of the influence of various factors on the fusion rate in patients with isthmic spondylolisthesis.Material and Methods. A retrospective monocenter study included data from 41 patients aged 18 years and older with isthmic spondylolisthesis who underwent transforaminal interbody fusion with cage using a four-screw rigid transpedicular fixation system. The influence of potential risk factors on the fusion rate was studied.Results. A univariate analysis showed that obesity (p = 0.037) and the use of non-steroidal anti-inflammatory drugs (NSAIDs) for more than three months (p = 0.007) significantly affect the formation of a bone block. When compiling a logistic regression model, it was found that a combination of obesity, smoking, and the use of NSAIDs for more than three months significantly worsens the prognosis of bone block formation (p = 0.007; R2N = 0.405; AUC = 0.850).Conclusion. The study showed that the absence of bone block formation in patients with isthmic spondylolisthesis may be associated with smoking, obesity, and the use of NSAIDs for more than three months. Keeping these factors in mind and trying to minimize their presence can help ensure better radiographic outcomes after surgery.