In vivo compatibility of Dynesys® spinal implants: a case series of five retrieved periprosthetic tissue samples and corresponding implants

Abstract

This is the first study to evaluate wear accumulation and local tissue responses for explanted Dynesys(®) devices. Polymer wear debris and an associated foreign-body macrophage response were observed in three of five cases.

Tribological evaluation of biomedical polycarbonate urethanes against articular cartilage

“…However, retrieved PCU spinal spacers (0.7 to 7 years) exhibited permanent deformation and surface damage (Ianuzzi et al, 2010). PCU wear debris and an associated macrophage response were also observed in some retrivals affected by major failures (Neukamp et al, 2015).…”

In vitro oxidative degradation of a spinal posterior dynamic stabilization device

“…Explanted orthopaedic implants, which contain PCU components, have demonstrated new absorbance peaks at 1650 cm −1 and/or 1174 cm −1 to demonstrate biological oxidative degradation . However, another explant study did not find new absorbance peaks linked to biological oxidative degradation .…”

Hyperspectral chemical imaging reveals spatially varied degradation of polycarbonate urethane (PCU) biomaterials

“…In particular, the polyurethane (PU) group, and more specifically polycarbonate urethanes (PCU), are used in vascular catheters [6,7] and orthopaedic [8][9][10][11] applications. Though PCU has been shown to be more biostable than polyether urethanes (PEU) [12,13], another polymer in the PU group used in cardiovascular applications [14], PCU components of explanted orthopaedic implants have been reported to degrade in the human body due to oxidation [9,15]. This oxidative degradation results in the cleavage of chemical bonds in a polymer [16] and has been shown to adversely affect the surface chemical structure of the PCU spacer of the Dynesys spinal stabilisation device (Zimmer, Warsaw, Indiana, USA) [15,[17][18][19].…”

“…Though PCU has been shown to be more biostable than polyether urethanes (PEU) [12,13], another polymer in the PU group used in cardiovascular applications [14], PCU components of explanted orthopaedic implants have been reported to degrade in the human body due to oxidation [9,15]. This oxidative degradation results in the cleavage of chemical bonds in a polymer [16] and has been shown to adversely affect the surface chemical structure of the PCU spacer of the Dynesys spinal stabilisation device (Zimmer, Warsaw, Indiana, USA) [15,[17][18][19]. To replicate and understand the effect of in vivo oxidation on chemical structure, an accelerated in vitro oxidation method to degrade PCU biomaterials has been reported [8,12,20].…”

“…Fourier transform infra-red (FTIR) spectroscopy is one of the three recommended techniques to quantify the chemical structure of polymers according to the ISO standard 10993-18, in addition to nuclear magnetic resonance (NMR) spectroscopy and mass spectroscopy (MS). Attenuated total reflectance Fourier transform infra-red (ATR-FTIR) spectroscopy has been used to understand and characterise the chemical structure changes of films [20,[22][23][24][25], tubing [23], dumbbell or cylindrical specimen shapes [26][27][28][29][30], pacemaker or defibrillator leads [14,31] and orthopaedic devices [8,15,[17][18][19]. A major limitation of standard ATR-FTIR, as conventionally applied, is that spectra are usually acquired from a single point of a sample.…”