Related Experiment Video
Updated: Sep 9, 2025

Three Dimensional Vestibular Ocular Reflex Testing Using a Six Degrees of Freedom Motion Platform
Published on: May 23, 2013
[Polyaxial angle stability]
Mark Lenz1, Mirko Rocci2, Martin Altmann2
1Klinik für Unfall‑, Hand- und Wiederherstellungschirurgie, Universitätsklinikum Jena, Jena, Deutschland.
Abstract:
Polyaxial screw systems are the state of the art in the field of fracture fixation. In contrast to conventional monoaxial systems, the polyaxial constructs enable variable screw angulation, enhancing the adaptability of plate-screw configurations in different surgical scenarios and different anatomical circumstances. This article provides a comprehensive overview of the functional principles, clinical applications and inherent limitations of polyaxial stability. The conventional monaxial technology restricts screw positioning, potentially compromising fixation in some fracture situations or anatomical regions. In contrast, polyaxial systems enable adapted screw placement, addressing specific requirements arising during surgery. Various locking mechanisms based on friction, deformation, thread forms and engagement techniques, play crucial roles in achieving stability. The article discusses the key currently used technologies, their mechanical characteristics and comparative behavior as the biomechanical interaction between screws and plates is crucial for achieving maximum stability and preventing failure modes that could compromise fracture healing. This article emphasizes that while polyaxial systems offer enhanced fragment-specific screw positioning, their successful application relies on careful surgical technique and an understanding of the mechanics involved. By integrating insights from clinical experiences, biomechanics, and the literature, we aim to raise awareness and support decision-making in fracture management using polyaxial systems. Ultimately, the article advocates a balanced understanding of both the benefits and challenges associated with polyaxial fracture fixation in modern orthopedic trauma surgery.
Related Concept Videos
Unsymmetric Bending - Angle of Neutral Axis
When a bending moment is applied at an angle θ concerning the vertical axis of a symmetrical member, it can be resolved into components along the member's principal...
Stability of structures
Stability of Equilibrium Configuration: Problem Solving
Problem-solving in the context of the stability of equilibrium configuration...
Pole and System Stability
Simple poles are unique roots of the denominator polynomial. Each simple pole corresponds to a distinct solution to the system's characteristic equation, typically resulting in exponential decay terms in the system's...
Eccentric Axial Loading in a Plane of Symmetry
Angle of Twist: Problem Solving

