Magnetic resonance imaging predictors of treatment outcome in patients with "failed back surgery" syndrome

Herniated lumbar intervertebral discs are the most common etiological cause of lumbar radiculopathy. Routine discectomy makes it possible to achieve the fastest regression of the clinical manifestations of the disease, although a significant proportion of patients demonstrate satisfactory results with conservative therapy. The purpose of the study was to determine the relationship between the initial data of magnetic resonance imaging (including central and foraminal stenosis, modal changes, disc morphological characteristics, faceted arthropathy, degree of disc degeneration, compression of nerve roots and dural sac) and the differential effect of surgical intervention. Materials and methods. Intervertebral hernia remains the leading cause of lumbar radiculopathy, which can be treated both surgically (discectomy) and nonoperatively. Despite the fact that MRI retains the status of a reliable "gold standard" of diagnosis, the degree of influence of its results on the effectiveness of various therapeutic approaches remains unclear. The study included one hundred and three complete tomographic images of patients who underwent the deidentification procedure and were evaluated by independent experts. The data obtained were compared with treatment outcome indicators, including the Oswestry disability index. A comparison of the results of surgical and conservative treatment was carried out between subgroups identified by image characteristics, and the therapeutic effect was determined based on differences in scores on the Oswestry index. Results. The study cohort included 40% of women with an average age of 41.5 ± 11.6 years, of whom 61% underwent discectomy for intervertebral herniation. Patients with surgical changes of type I end plates had less favorable outcomes after surgery (p = 0.003). Patients with compression ≥1/3 showed the greatest improvement in the surgical group (p=0.007) and the highest treatment rate (p=0.015). In addition, patients with minimal nerve root injury showed worse surgical results (p=0.016). Conclusion. Among people with a herniated disc, a more pronounced positive effect of surgical intervention was observed in patients with dural sac compression ≥ 1/3, compared with patients with small hernias and modal changes of type I. In addition, the best results of surgical treatment were observed in patients with significant displacement or compression of the nerve roots compared with patients with only minimal pinching of the roots