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In Vivo Prevention of Implant-Associated Infections Caused by Antibiotic-Resistant Bacteria through Biofunctionalization of Additively Manufactured Porous Titanium

van Hengel, I.A.J. (author), van Dijk, B. (author), Modaresifar, K. (author), Hooning van Duyvenbode, J. Fred F. (author), Nurmohamed, F. Ruben H.A. (author), Leeflang, M.A. (author), Fluit, A.C. (author), Fratila-Apachitei, E.L. (author), Apachitei, I. (author), Weinans, Harrie (author), Zadpoor, A.A. (author)

Additively manufactured (AM) porous titanium implants may have an increased risk of implant-associated infection (IAI) due to their huge internal surfaces. However, the same surface, when biofunctionalized, can be used to prevent IAI. Here, we used a rat implant infection model to evaluate the biocompatibility and infection prevention...

journal article 2023

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Patient-specific 3D-printed shelf implant for the treatment of hip dysplasia: Anatomical and biomechanical outcomes in a canine model

Willemsen, Koen (author), Tryfonidou, Marianna (author), Sakkers, Ralph (author), Castelein, René M. (author), Zadpoor, A.A. (author), Seevinck, Peter (author), Weinans, Harrie (author), Meij, Björn (author), van der Wal, Bart C.H. (author)

A solution for challenging hip dysplasia surgery could be a patient-specific 3D-printed shelf implant that is positioned extra-articular and restores the dysplastic acetabular rim to normal anatomical dimensions. The anatomical correction and biomechanical stability of this concept were tested in a canine model that, like humans, also suffers...

journal article 2022

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Topographic features of nano-pores within the osteochondral interface and their effects on transport properties –a 3D imaging and modeling study

Pouran, Behdad (author), Raoof, Amir (author), de Winter, D. A.Matthijs (author), Arbabi, V. (author), Bleys, Ronald L.A.W. (author), Beekman, F.J. (author), Zadpoor, A.A. (author), Malda, Jos (author), Weinans, Harrie (author)

Recent insights suggest that the osteochondral interface plays a central role in maintaining healthy articulating joints. Uncovering the underlying transport mechanisms is key to the understanding of the cross-talk between articular cartilage and subchondral bone. Here, we describe the mechanisms that facilitate transport at the osteochondral...

journal article 2021

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Additively manufactured space-filling meta-implants

Kolken, H.M.A. (author), de Jonge, C.P. (author), van der Sloten, T. (author), Garcia, A. Fontecha (author), Pouran, B. (author), Willemsen, K. (author), Weinans, Harrie (author), Zadpoor, A.A. (author)

The unprecedented properties of meta-biomaterials could pave the way for the development of life-lasting orthopedic implants. Here, we used non-auxetic meta-biomaterials to address the shortcomings of the current treatment options in acetabular revision surgery. Due to the severe bone deficiencies and poor bone quality, it can be very...

journal article 2021

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Mechanical performance of auxetic meta-biomaterials

Kolken, H.M.A. (author), Lietaert, K. (author), van der Sloten, T. (author), Pouran, B. (author), Meynen, A. (author), Van Loock, G. (author), Weinans, Harrie (author), Scheys, L. (author), Zadpoor, A.A. (author)

The innovative design of orthopedic implants could play an important role in the development of life-lasting implants, by improving both primary and secondary implant fixations. The concept of meta-biomaterials aims to achieve a unique combination of mechanical, mass transport, and biological properties through optimized topological design of...

journal article 2020

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Functionality-packed additively manufactured porous titanium implants

van Hengel, I.A.J. (author), Gelderman, F. S.A. (author), Athanasiadis, S. (author), Minneboo, M.B. (author), Weinans, Harrie (author), Fluit, A. C. (author), van der Eerden, B.C.J. (author), Fratila-Apachitei, E.L. (author), Apachitei, I. (author), Zadpoor, A.A. (author)

The holy grail of orthopedic implant design is to ward off both aseptic and septic loosening for long enough that the implant outlives the patient. Questing this holy grail is feasible only if orthopedic biomaterials possess a long list of functionalities that enable them to discharge the onerous task of permanently replacing the native bone...

journal article 2020

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Bone regeneration in critical-sized bone defects treated with additively manufactured porous metallic biomaterials: The effects of inelastic mechanical properties

Koolen, Marianne (author), Amin Yavari, S. (author), Lietaert, Karel (author), Wauthle, Ruben (author), Zadpoor, A.A. (author), Weinans, Harrie (author)

Additively manufactured (AM) porous metallic biomaterials, in general, and AM porous titanium, in particular, have recently emerged as promising candidates for bone substitution. The porous design of such materials allows for mimicking the elastic mechanical properties of native bone tissue and showed to be effective in improving bone...

journal article 2020

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Three-dimensional analysis of shape variations and symmetry of the fibula, tibia, calcaneus and talus

Tümer, N. (author), Arbabi, V. (author), Gielis, Willem Paul (author), de Jong, Pim A. (author), Weinans, Harrie (author), Tuijthof, Gabrielle J.M. (author), Zadpoor, A.A. (author)

The bones forming the talocrural joint (TCJ) and subtalar joint (STJ) are often assumed to be bilaterally symmetric. Therefore, the contralateral limb (i.e. the fibula, tibia, calcaneus and talus) is used as a template or an intra-subject control in clinical and research practice. However, the validity of the symmetry assumption is...

journal article 2019

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Early signs of bone and cartilage changes induced by treadmill exercise in rats

Rahnamay Moshtagh, P. (author), Korthagen, Nicoline M. (author), Plomp, Saskia G. (author), Pouran, B. (author), Castelein, Rene M. (author), Zadpoor, A.A. (author), Weinans, Harrie (author)

This study aims to investigate the earliest alterations of bone and cartilage tissues as a result of different exercise protocols in the knee joint of Wistar rats. We hypothesize that pretraining to a continuous intense running protocol would protect the animals from cartilage degeneration. Three groups of animals were used: (i) an adaptive ...

journal article 2018

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Rationally designed meta-implants: a combination of auxetic and conventional meta-biomaterials

Kolken, H.M.A. (author), Janbaz, S. (author), Leeflang, M.A. (author), Lietaert, K. (author), Weinans, Harrie (author), Zadpoor, A.A. (author)

Rationally designed meta-biomaterials present unprecedented combinations of mechanical, mass transport, and biological properties favorable for tissue regeneration. Here we introduce hybrid meta-biomaterials with rationally-distributed values of negative (auxetic) and positive Poisson’s ratios, and use them to design meta-implants that unlike...

journal article 2018

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Additively manufactured biodegradable porous iron

Li, Y. (author), Jahr, H. (author), Lietaert, K. (author), Pavanram, P. (author), Yilmaz, A. (author), Fockaert, L.I. (author), Leeflang, M.A. (author), Pouran, B. (author), Gonzalez Garcia, Y. (author), Weinans, Harrie (author), Mol, J.M.C. (author), Zhou, J. (author), Zadpoor, A.A. (author)

Additively manufactured (AM) topologically ordered porous metallic biomaterials with the proper biodegradation profile offer a unique combination of properties ideal for bone regeneration. These include a fully interconnected porous structure, bone-mimicking mechanical properties, and the possibility of fully regenerating bony defects. Most...

journal article 2018

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Non-enzymatic cross-linking of collagen type II fibrils is tuned via osmolality switch

Pouran, B. (author), Moshtagh, Parisa R. (author), Arbabi, V. (author), Snabel, Jessica (author), Stoop, Reinout (author), Ruberti, Jeffrey (author), Malda, Jos (author), Zadpoor, A.A. (author), Weinans, Harrie (author)

An important aspect in cartilage ageing is accumulation of advanced glycation end products (AGEs) after exposure to sugars. Advanced glycation results in cross-links formation between the collagen fibrils in articular cartilage, hampering their flexibility and making cartilage more brittle. In the current study, we investigate whether...

journal article 2018

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Fatigue performance of additively manufactured meta-biomaterials: The effects of topology and material type

Ahmadi, S.M. (author), Hedayati, R. (author), Li, Y (author), Lietaert, K. (author), Tümer, N. (author), Fatemi, A. (author), Rans, C.D. (author), Pouran, B. (author), Weinans, Harrie (author), Zadpoor, A.A. (author)

Additive manufacturing (AM) techniques enable fabrication of bone-mimicking meta-biomaterials with unprecedented combinations of topological, mechanical, and mass transport properties. The mechanical performance of AM meta-biomaterials is a direct function of their topological design. It is, however, not clear to what extent the material type...

journal article 2018

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Unfocused shockwaves for osteoinduction in bone substitutes in rat cortical bone defects

Koolen, Marianne K.E. (author), Pouran, B. (author), Oner, Fetullah C. (author), Zadpoor, A.A. (author), van der Jagt, Olav P. (author), Weinans, Harrie (author)

Bone substitutes are frequently used in clinical practice but often exhibit limited osteoinductivity. We hypothesized that unfocused shockwaves enhance the osteoinductivity of bone substitutes and improve osteointegration and angiogenesis. Three different bone substitutes, namely porous tricalcium phosphate, porous hydroxyapatite and porous...

journal article 2018

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In-silico quest for bactericidal but non-cytotoxic nanopatterns

Mirzaali, Mohammad J. (author), Van Dongen, I. C.P. (author), Tümer, N. (author), Weinans, Harrie (author), Amin Yavari, S. (author), Zadpoor, A.A. (author)

Nanopillar arrays that are bactericidal but not cytotoxic against the host cells could be used in implantable medical devices to prevent implant-associated infections. It is, however, unclear what heights, widths, interspacing, and shape should be used for the nanopillars to achieve the desired antibacterial effects while not hampering the...

journal article 2018

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Additively manufactured metallic porous biomaterials based on minimal surfaces: A unique combination of topological, mechanical, and mass transport properties

Bobbert, F.S.L. (author), Lietaert, K. (author), Eftekhari, A.A. (author), Pouran, B. (author), Ahmadi, S.M. (author), Weinans, Harrie (author), Zadpoor, A.A. (author)

Porous biomaterials that simultaneously mimic the topological, mechanical, and mass transport properties of bone are in great demand but are rarely found in the literature. In this study, we rationally designed and additively manufactured (AM) porous metallic biomaterials based on four different types of triply periodic minimal surfaces (TPMS)...

journal article 2017

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Additively manufactured biodegradable porous magnesium

Li, Y. (author), Zhou, J. (author), Pavanram, P. (author), Leeflang, M.A. (author), Fockaert, L.I. (author), Pouran, B. (author), Tümer, N. (author), Schröder, K. U. (author), Mol, J.M.C. (author), Weinans, Harrie (author), Jahr, H. (author), Zadpoor, A.A. (author)

An ideal bone substituting material should be bone-mimicking in terms of mechanical properties, present a precisely controlled and fully interconnected porous structure, and degrade in the human body to allow for full regeneration of large bony defects. However, simultaneously satisfying all these three requirements has so far been highly...

journal article 2017

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Simultaneous delivery of multiple antibacterial agents from additively manufactured porous biomaterials to fully eradicate planktonic and adherent Staphylococcus aureus

Bakhshandeh, S. (author), Gorgin Karaji, Z. (author), Lietaert, K. (author), Fluit, A.C. (author), Boel, C.H.E. (author), Vogely, H.C. (author), Vermonden, T. (author), Hennink, W. E. (author), Weinans, Harrie (author), Zadpoor, A.A. (author), Amin Yavari, S. (author)

Implant-associated infections are notoriously difficult to treat and may even result in amputation and death. The first few days after surgery are the most critical time to prevent those infections, preferably through full eradication of the micro-organisms entering the body perioperatively. That is particularly important for patients with a...

journal article 2017

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Geometry-based control of instability patterns in cellular soft matter

Janbaz, S. (author), Weinans, H. (author), Zadpoor, A.A. (author)

Recent research has shown the potential of rationally designed geometrical features for controlling the functionality of advanced materials. Of particular recent interest has been the use of geometry for controlling the buckling behaviour of soft materials under compression. However, the effects of geometry may be mixed with those of the...

journal article 2016

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Combined inverse-forward artificial neural networks for fast and accurate estimation of the diffusion coefficients of cartilage based on multi-physics models

Arbabi, V. (author), Pouran, B. (author), Weinans, Harrie (author), Zadpoor, A.A. (author)

Analytical and numerical methods have been used to extract essential engineering parameters such as elastic modulus, Poisson's ratio, permeability and diffusion coefficient from experimental data in various types of biological tissues. The major limitation associated with analytical techniques is that they are often only applicable to problems...

journal article 2016