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A multimodal approach combining inductively coupled plasma mass spectrometry (ICP-MS), single-particle ICP-MS (spICP-MS), scanning electron microscopy-energy-dispersive X-ray spectroscopy (SEM-EDS) and Raman spectroscopy enabled a deeper insight into the balance between total titanium (Ti), the soluble titanium fraction and titanium dioxide based particle fraction levels in periprosthetic tissues collected from patients undergoing revision surgery. Hydrofluoric acid usage in the sample digestion allowed for complete digestion of TiO2 particles, thus enabling accurate estimation of total Ti levels. The TiO2 fraction represents 38–94% of the titanium load in the six samples where particles were detected, and the fraction is present mainly in samples from patients with aseptically loosened total hip arthroplasty. Further attention was given to this fraction determining the elemental composition, particle count, particle size and modification of TiO2. The spICP-MS analysis confirmed the presence of the TiO2-derived (nano)particles (NPs) with a 39- to 187-nm median size and particle count up to 2.3 × 1011 particles per gram of tissue. On top of that, the SEM-EDS confirmed the presence of the TiO2 nanoparticles with 230-nm median size and an anatase crystal phase was determined by Raman spectroscopy. This study presents a novel multimodal approach for TiO2 particle determination and characterization in tissue samples and is the first in vivo study of this character. [ABSTRACT FROM AUTHOR]

This unique study provides information on Cr species and their distribution in periprosthetic tissues of patients with metal‐on‐polyethylene joint implants. Co–Cr–Mo alloy has been widely used in joint replacement and represents a source of metal derived species. In the case of chromium, previous studies on periprosthetic tissues revealed mainly Cr(III) distribution, whereas the potential release of carcinogenic Cr(VI) species has been still a subject of debate. Here, an analytical approach utilizing speciation and fractionation was developed to analyze periprosthetic tissue samples collected from wide range of patients with failed total hip or knee replacements. The results reveal that Cr(III) is mainly released in the form of insoluble CrPO4 and Cr2O3 particles. The highest Cr contents were found in periprosthetic tissues of patients suffering from aseptic loosening and having more Cr‐based implants in the body. Cr species penetrated tissue layers, but their levels decreased with the distance from an implant. The detailed speciation/fractionation study carried out using the set of consecutive periprosthetic tissues of a patient with extensive metallosis showed the presence of trace amounts of free Cr(III), nanoparticles, and metal‐protein complexes, but the majority of Cr still occurred in CrPO4 form. Carcinogenic Cr(VI) species were not detected. Up to date, there is no published human tissue study focused on the detailed speciation of both soluble and insoluble Cr‐based species in the context of failing total hip and knee replacements. [ABSTRACT FROM AUTHOR]

This prospective study examined the content of metals released from total joint arthroplasty into joint fluid, whole blood and periprosthetic tissues. We determined the levels of Ti, V, Nb, Co, Cr, and Mo, using inductively coupled plasma mass spectrometry, in samples from patients who underwent reoperation of total hip or knee arthroplasty. All of the patients (n = 117) included in the study had either metal on polyethylene or ceramic on polyethylene‐bearing pairs. First, our results conclusively showed that the majority of released metals were deposited in periprosthetic tissues. In this context, the bloodstream turned out to be an ineffective biomarker of the effects occurring in local tissues. Second, there was a clear time‐dependent nature of metallic accumulation. Based on our extensive dataset, we found significantly elevated levels of the released metals in joint fluid and periprosthetic tissues originating from loosened implants compared to stable ones, as well as recognizable differences between the groups with stable implants and aseptic loosening. Finally, it was proved that the concentrations of metals decreased dependent on the distance of the tissue from the implant. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 107B: 454–462, 2019. [ABSTRACT FROM AUTHOR]

Wear analysis of total hip replacements (THRs) is considered one of the most relevant research areas helping to improve the longevity and overall design of THRs. The coordinate machine method (CMM) and Fourier profilometry are the most common methods for measuring THR wear. This article presents optical scanner digitalization as a new method for measuring the wear of polyethylene (PE) acetabular cups. The aim of this article is to explore the potential of this method for the PE wear measurements. Optical scans for the purposes of this study were produced using an ATOS Triple Scan 3D optical scanner. The optical scanner is efficient and it can measure a large number of points for polygonization and for further development of the preworn models. In this study, the scanner first generated point clouds on a sample of 13 retrieved ultra-high-molecular-weight polyethylene (UHMWPE) acetabular cups. Next, volumetric models of the cups were created by polygonizing the point clouds. Reverse engineering was used to develop models of the original acetabular cups using the geometry of the unworn parts of the retrieved cups. A comparison of the two models then showed the total volume of the PE debris. The optical scanning method was validated against the gravimetric method using three new acetabular cups that were worn out on a hip pendulum simulator. Validation shows that the optical scanning method is a valid method for wear analysis of the retrieved UHMWPE acetabular cups. [ABSTRACT FROM AUTHOR]

Low back pain (LBP) is a painful disease which results in limitations on normal daily physical activities related to self-care, social contact and communication. Physiotherapy combined with spa treatments and hippotherapy could be a suitable treatment method recommended in patients with LBP. The purpose of the study was to determine the effect of standard physiotherapy with and without hippotherapy on gait kinematic parameters in patients with chronic LBP. A total of 23 patients suffering from LBP with a damage located between L4 and S1 segments were enrolled in the study. Thirteen of them (the experimental group) underwent in addition to standard physiotherapy also hippotherapy. Physiotherapy intervention and hippotherapy units were performed at the Darkov Spa, Czech Republic. The kinematic gait parameters were obtained by the Vicon MX system. The intensity of the pain was determined using the visual analogue pain scale (VAS). After the intervention, we found statistically significant increase in the range of motion the knee joint in the sagittal plane (P < 0.05) as well as the flexion in the hip joint (P<0.05) in the experimental group. Similar trends were observed in the control group. Only two significant differences (P<0.05) between lower extremities with and without pain propagation were detected for the experimental group while for the control group the number of differences increased after the intervention. VAS pain score decreased in both groups but significantly (P < 0.01) only in the experimental group. Particular physiotherapy protocol had an observable effect on the gait kinematics in the patients with chronic LBP. A significant effect of hippotherapy on the symmetry of gait and VAS pain score was found. [ABSTRACT FROM AUTHOR]