Table 2. Overview of dynamic devices used in the included studies comparing dynamic stabilization with fusion.

Author	Dynamic device	Description	Proposed design benefit(s)
Kaner et al4 (2010)	Cosmic dynamic pedicular screw-rod system (Ulrich GmbH & co KG, Ulm, Germany)	Hinged-pedicle screws combined with rigid rods	Allows axial motion, reducing stress at the bone-screw interface
Korovessis et al2 (2004)	Twinflex rod system (Eurosurgical, Ireland) Claris instrumentation (Eurosurgical, Ireland)	Two pairs of flexible stainless steel rods (2.5 mm) and flat connectors for each instrumented level Longitudinal, smooth “semirigid” rods (6 mm) connected transversely with a thin (2 mm) flat connector to the pedicle screw head	Flexibility of the longitudinal connections allows the instrumentation to adapt to any screw placement in both alignment and direction Dynamic loading of the bone graft occurs as a result of the elasticity of the construct
Lee et al6 (2010)	Interspinous soft stabilization (ISS) with tension band system (Ligament Vertebral de Renfort; Cousine Biotech, Wervicq-sud, France)	Composed of polyester, polyethylene terephthalate, and a central thread of barium, platinum radiopaque silicone	Achieve regional lumbar lordosis by placing the motion segment into extension
Ozer et al5 (2010)	Dynamic (hinged) pedicle screw (Spahinaz, Medikon AS, Turkey)	Hinged-pedicle screws combined rigid rods	Allows axial motion, reducing stress at the bone-screw interface