Should Iliac Wing Screws Be Included in Long Segment Dynamic Stabilization?

Area of Science:

• Spine surgery
• Orthopedics
• Biomechanical engineering

Background:

• Dynamic stabilization is a surgical option for spinal instability causing pain.
• The Dynesys system is commonly used for multilevel instabilities.
• S1 screw loosening is a known complication of the Dynesys system.

Purpose of the Study:

• To address S1 screw insufficiency in dynamic stabilization.
• To evaluate the efficacy of extending stabilization to the iliac wings.

Main Methods:

• Nineteen patients with multilevel instability underwent dynamic stabilization including iliac wings.
• Patient follow-up utilized the Visual Analog Scale (VAS) and Oswestry Disability Index (ODI).

Main Results:

• Significant improvements in VAS and ODI were observed in the first year.
• Complications included infection (1), proximal iliac wing loosening (1), and combined S1/iliac loosening (1), with no clinical symptoms.

Conclusions:

• S1 screw loosening is common with multi-level Dynesys use in elderly patients with chronic instability.
• Incorporating iliac bones into stabilization successfully resolves S1 screw loosening.
• The current Dynesys system lacks suitable screws for iliac bone fixation.