Use of Dynamic Spinal Instruments (Dynesys) in Adult Spinal Deformities According to Silva-Lenke and Berjano-Lamartina Classifications.

Background: Adult spinal deformities (ASD) present complex challenges in spine surgery. The diverse nature of these deformities requires a comprehensive understanding of their classification and treatment options. Traditional approaches, such as fusion and rigid stabilization are associated with complications, including screw loosening, breakage, proximal junctional kyphosis (PJK), and pseudoarthrosis. Dynamic stabilization techniques have emerged as promising alternatives, to reduce these complications and preserve spinal motion.

Objective: This study investigated the effectiveness of dynamic stabilization using the Dynesys system in the surgical treatment of adult degenerative spinal deformities, with a particular emphasis on their classification.

Methods: ASDs were classified according to the Berjano-Lamartina (BL) and Silva-Lenke (SL) classifications. We analyzed the efficacy of the Dynesys system in enhancing sagittal balance, radiological parameters, and clinical outcomes in this context.

Results: Dynamic stabilization of patients with ASDs using the Dynesys system significantly improved the visual analog scale and Oswestry Disability Index scores and decreased the complication rates. Patients with BL types 2, 3, and 4 experienced a significant improvement in sagittal balance followed by sagittal vertical axis measurements ( = 0.045, = 0.015, and < 0.0001, respectively).

Conclusion: The SL and BL classifications, which were originally developed for rigid spinal stabilization, can be applied in dynamic stabilization. Furthermore, dynamic stabilization using the Dynesys system can be used as an alternative to rigid stabilization in SL levels 2 and 3, and BL types 1, 2, and 3, and in some patients with type 4 ASDs.