Evaluating the performance of a novel double-threaded dynamic stabilization system: a finite element study.

Abstract

To evaluate the biomechanical performance of a novel dual-cord and dual-spacer posterior dynamic stabilization system compared to a conventional single-threaded construct. A validated finite element (FE) model of the L1-S1 lumbar spine was developed. Posterior dynamic stabilization was simulated at the L4-L5 segment using two systems: a traditional polyethylene terephthalate (PET) cord with polycarbonate urethane (PCU) spacer (single-threaded), and a dual PET cord-spacer construct. Both systems were analyzed under full range of motion (ROM) loading and physiological loads using Abaqus software to simulate stress distribution and motion. The dual-cord system enhanced segmental stability at L4-5 by approximately 22% while preserving adjacent level mobility within normal physiological limits. Peak stress levels on implant components increased marginally but remained within safe thresholds. The dual-cord dynamic stabilization system demonstrates improved biomechanical stability with minimal adjacent segment compromise. These results support its potential for reducing long-term mechanical failure risks in lumbar stabilization.