Orthopedic Devices Research Articles

Electrophoretic deposition of moringa loaded chitosan coatings on Mg: A study on antibacterial properties and degradation kinetics

Moringa loaded chitosan coatings (coating thickness ∼10 µm) were deposited on Mg substrate via electrophoretic deposition (applied electric field = 15 V/cm and deposition time = 20 min). Scanning electron microscopy images of chitosan/moringa coatings confirmed that the deposited coatings are densely packed and uniform. The presence of chitosan and moringa in the coating was confirmed by Fourier transform infrared spectroscopy. The corrosion studies revealed that the degradation rate of bare Mg decreased ∼7 order of magnitude upon coating deposition. Furthermore, the potential release of moringa from coatings inhibited the growth of Staphylococcus aureus and Escherichia coli. The moringa loaded chitosan coatings presented suitable morphology, electrochemical properties, and antibacterial properties for potential application in orthopedic devices.

Fabrication and Characterization of Zn Particle Incorporated Fibrous Scaffolds for Potential Application in Tissue Healing and Regeneration.

Zinc (Zn) metal and its alloys have received a lot of interest in biomedical applications due to their biodegradability, biocompatibility, antimicrobial activity, and ability to stimulate tissue regeneration. Bulk Zn has been successfully utilized in a variety of implant applications, most notably as bioabsorbable cardiac stents and orthopedic fixation devices, where it provides adequate mechanical properties while also releasing helpful Zn ions (Zn2+) during degradation. Such beneficial ions are dose-dependent and, when released in excess, can induce cellular toxicity. In this study, we hypothesize that embedding Zn metal particles into a polymer nanofibrous scaffold will enable control of the degradation and time release of the Zn2+. We designed and fabricated two polymer scaffolds, polycaprolactone (PCL) and polycaprolactone-chitosan (PCL-CH). Each scaffold had an increasing amount of Zn. Several physicochemical properties such as fiber morphology, crystallinity, mechanical strength, hydrophilicity, degradation and release of Zn2+, thermal properties, chemical compositions, and so forth were characterized and compared with the PCL fibrous scaffold. The biological properties of the scaffolds were evaluated in vitro utilizing direct and indirect cytotoxicity assays and cell viability. All the data show that the addition of Zn changed various physical properties of the PCL and PCL-CH scaffolds except their chemical structure. Further investigation reveals that the PCL-CH scaffolds degrade the Zn particles relatively faster than the PCL because the presence of the hydrophilic CH influences the faster release of Zn2+ in cell culture conditions as compared to the PCL fibrous scaffold. The combined advantages of CH and Zn in the PCL scaffold enriched 3T3 fibroblast cells' survival and proliferation except the ones with the higher concentration of Zn particles. These new composite scaffolds are promising and can be further considered for tissue healing and regeneration applications.

Research progress in degradable metal‐based multifunctional scaffolds for bone tissue engineering

AbstractThe increasing prevalence of orthopedic‐related diseases necessitates the development of effective orthopedic implants. Conventional metal scaffolds used in orthopedic devices have limitations such as poor biocompatibility and the need for a second surgery to remove the scaffold. Degradable metal‐based scaffolds, including metal‐based scaffolds and multifunctional scaffolds doped with metal elements, are a rapidly developing tissue engineering strategy aimed at utilizing the mechanical and biological properties of metal elements to create a support structure that matches the complex bone regeneration environment. Repairing bone defects involves the regeneration of various tissues, and incomplete repair can negatively affect bone function and overall recovery. Therefore, combining metal‐based degradable materials with other active components has great potential for enhancing the versatility and clinical applications of scaffolds. Multifunctional scaffolds doped with metal elements have better biocompatibility, osteoinductivity, biodegradability, matching mechanical, and microenvironmental adjustment capabilities. Moreover, these metal‐doped scaffolds possess the advantages of controlled release of metal ions, multifunctionality, and faster degradation. This review focuses on the materials and techniques used for constructing degradable metal‐based scaffolds. Furthermore, this study discussed the potential for designing and constructing multifunctional biodegradable metal‐based scaffolds doped with metal elements by integrating multiple strategies.

Development and Research Progress of 3D Printing Technology in Orthopedic Medical Devices

With the characteristics of fast prototyping and personalized manufacturing, 3D-printing (three-dimensional printing) is an emerging technology with promising applications for orthopedic medical devices. It can complete the process of medical devices with complex shape which can not be completed by conventional fabrication process. At present, a variety of orthopedic medical devices manufactured by 3D printing technology, has been approved for marketing, and their use has been proved to be beneficial. 3D bioprinting in this area has also made a few breakthroughs. However, many challenges still remain to be addressed as well. In this study, the research status, as well as the development of the 3D-printing technology in the field of orthopedic medical devices is elaborated.

Discussion and Concern on Animal Study for Orthopaedic Implantable Devices

In recent years, new orthopaedic implantable devices continue to emerge, which require higher requirements for technical evaluation. Animal study is an important part of the research and development process for the new orthopedic implantable devices, which provides relevant evidence for product design and stereotyping. By introducing the purpose of animal study, and the application of 3R principle (replacement, reduction, refinement) in this field, we summarize the concern on the animal study, in order to provide reference for the development and research of new orthopedic implantable devices and biomaterials. At the same time, the application of evidence-based research methods such as systematic review in the field is introduced, which provides new tools and approaches for the technical review and regulatory science.

Fatigue behavior of additively manufactured Ti3Al2V alloy.

This study measured the tensile, compression, and fatigue behavior of additively manufactured Ti3Al2V as a function of build orientation. Ti3Al2V alloy was prepared by mixing commercially pure titanium (CpTi) and Ti6Al4V in 1:1 wt. ratio. Laser powder bed fusion (L-PBF) based additive manufacturing (AM) technique was used to fabricate the samples. Tensile tests resulted in an ultimate strength of 989 ± 8 MPa for Ti3Al2V. Ti6Al4V 90° orientation samples showed a compressive yield strength of 1178 ± 33 MPa, and that for Ti3Al2V 90° orientation was 968 ± 24 MPa. Varying the build orientation to account for anisotropy, Ti32-45° and Ti32-0° displayed similar compressive yield strength values of 1071 ± 16 and 1051± 18 MPa, respectively, higher than Ti32-90°. Fatigue loading revealed an endurance limit (10 million cycles) of 250 MPa for Ti6Al4V and 219 MPa for Ti3Al2V built at 90° orientations. The effect of the build orientation was significant under fatigue loading; Ti3Al2V built at 45° displayed an endurance limit of 387.5 MPa, and 0° showed 512 MPa; more than two-fold increment in endurance limit was observed. Our results show the potential of Ti3Al2V alloy for orthopedic devices, replacing Ti6Al4V alloy, particularly in load-bearing applications.

Finite Element Parametric Design of Hallux Valgus Orthosis Based on Orthogonal Analysis.

To design appropriate orthosis for hallux valgus, a difficult foot condition that affects a quarter of the body's bones, we need to clarify the numerical biomechanical features, which have not been established in previous biomechanical studies. Therefore, we constructed a finite element model of the bunion foot to investigate the orthopaedic force compensation mechanism. A patient with moderate hallux valgus was recruited. CT imaging data in DICOM format were extracted for three-dimensional foot model reconstruction. In conjunction with the need for rapid design of bunion orthosis, a metatarsal force application sizing method based on an orthogonal test design was investigated. The orthogonal test design was used to obtain the hallux valgus angle (HVA) and the inter metatarsal angle (IMA) data for different force combinations. Based on the extreme difference analysis and analysis of variance of the test results, the influence of different force combinations on the bunion angle was quickly determined. The results showed that the stress concentration occurred mainly in the first metatarsal bone. The distribution trend was in the medial and lateral middle of the bone and gradually decreased to the dorsal base of the bone body. The greatest stress occurs in the cartilage between the phalanges and metatarsals. In 25 groups of simulation experiments, HVA was reduced from 27.7° to 13°, and IMA was reduced from 12.5° to 7.3°. Applying detailed orthopaedic force collocation to the first metatarsal column can effectively restore the mechanics and kinematics of hallux valgus, and provide a reference for the treatment of bunion valgus and the design of orthopaedic devices.

An Electrochemical Approach to Accelerate Mechanically Assisted Crevice Corrosion Damage on Modular Implant Interfaces

Abstract Corrosion within the crevice of modular tapers is one of the major mechanisms that leads to orthopedic device failures. However, the currently used fretting corrosion test methods involve extended test durations and are often burdensome. This study evaluates the feasibility of adding micromotion to crevices while being simultaneously subjected to cyclic polarization in order to accelerate corrosion damage. The addition of micromotion was intended to induce crevice and fretting corrosion between metals in a washer-rod combination geometry. Three commonly used orthopedic metals (316L stainless steel, SS316L; grade 5 titanium, Ti6Al4V; and cobalt-chromium-molybdenum per ASTM F1537-20, Standard Specification for Wrought Cobalt-28Chromium-6Molybdenum Alloys for Surgical Implants [UNS R31537, UNS R31538, and UNS R31539], CoCrMo) were used to form crevices in this study to evaluate the test method. A cyclic polarization control group in which no micromotion was present was used to determine the effect of the cyclic polarization alone. In addition, a fretting control group in which no cyclic polarization was conducted was used to assess the effect of micromotion without cyclic polarization. The results of this study showed that fretting corrosion damage can be achieved on Ti6Al4V and SS316L washer crevices when subjected to micromotion alone. The test method did not induce more corrosion on Ti6Al4V samples when crevices were tested with cyclic polarization alone. Furthermore, the results found that cyclic polarization in combination with micromotion did not achieve the same fretting corrosion damage on the CoCrMo samples as observed in explants. Still, electrochemical test methods have potential for accelerating corrosion damage within crevices when combined with existing fretting corrosion testing and therefore could potentially reduce test durations for fretting corrosion susceptibility evaluations for medical devices having modular taper connections.

Metal hypersensitivity in foot & ankle orthopaedic surgery: A systematic review

IntroductionMetal hypersensitivity affects 10–15% of individuals. Orthopaedic implants contain various metals and, therefore, metal hypersensitivity may impact patient outcomes. PurposeWe report a systematic review of the literature on metal hypersensitivity in patients undergoing foot and ankle (F&A) surgery. Our goal is to provide an overview presenting symptoms, diagnostic methods, treatment, and clinical outcomes. MethodsA comprehensive literature search of Ovid MEDLINE and EMBASE was performed from its inception (01-Jan 1966) to 23-Nov 2021. MeSH search terms on F&A were used including orthopaedic surgeries, metal types, and hypersensitivity. All full-text, English, experimental and observational studies reporting on metal hypersensitivity in the context of foot and/or ankle surgeries using metallic orthopaedic devices were included. Article screening, critical appraisal, and data extraction was performed by two reviewers. Disagreements were resolved by a third reviewer. ResultsFifteen studies were identified, reporting on 45 patients (18 male and 27 female). Median age was 58 years and mean follow-up was 20.8 months. 42 static and three arthroplasty implants were included. In total, 19 patients (42.2%) were diagnosed with metal hypersensitivity to a constituent of their implant, including two (4.4%) patients diagnosed without metal hypersensitivity testing. Twenty-six patients (57.8%) tested negative to their metal implant components. Of the 19 patients allergic to a constituent of their implant, 14 underwent hardware removal and improved. Four patients were asymptomatic and the last was symptomatic, but not revised. Of these, 23 patients retained their hardware (eight with skin reactions) and two symptomatic patients underwent hardware removal. ConclusionMetal hypersensitivity in the context of F&A surgery is not widely reported. It should be a differential diagnosis in patients who present with hypersensitivity-type symptoms once infection and mechanical failure are ruled out. This data informs a comprehensive algorithm for identifying and treating metal hypersensitivity in F&A patients. Level of evidenceLevel IV.

New developments in combating infection from biofilm forming bacteria of orthopedic implants

Orthopedic device related infections (ODRI’s) represent a difficult to treat situation owing to their biofilm based nature. Biofilm infections once established are difficult to eradicate even with an aggressive treatment regimen due to their recalcitrance towards antibiotics and immune attack. The definitive treatment to eradicate the infections once a biofilm has established is surgical excision of the implant and thorough local debridement, but this carries a significant socioeconomic cost, the outcomes for the patient are often poor, and there is a significant risk of recurrence. The aim of the study was to provide a comprehensive insight into the newer anti-biofilm interventions (non-antibiotic approaches) and a better understanding of their mechanism of action essential for improved management of orthopedic implant infections.

Multidimensional analysis for the correlation of physico-chemical attributes to osteoblastogenesis in TiNbZrSnTa alloys

Data-enabled approaches that complement experimental testing offer new capabilities to investigate the interplay between chemical, physical and mechanical attributes of alloys and elucidate their effect on biological behaviours. Reported here, instead of physical causation, statistical correlations were used to study the factors responsible for the adhesion, proliferation and maturation of pre-osteoblasts MC3T3-E1 cultured on Titanium alloys. Eight alloys with varying wt% of Niobium, Zirconium, Tin and Tantalum (Ti— (2–22 wt%)Nb— (5–20 wt%)Zr— (0–18 wt%)Sn— (0–14 wt%)Ta) were designed to achieve exemplars of allotropes (incl., metastable-β, β + α′, α″). Following confirmation of their compositions (ICP, EDX) and their crystal structure (XRD, SEM), their compressive bulk properties were measured and their surface features characterised (XPS, SFE). Because these alloys are intended for the manufacture of implantable orthopaedic devices, the correlation focuses on the effect of surface properties on cellular behaviour. Physico-chemical attributes were paired to biological performance, and these highlight the positive interdependencies between oxide composition and proliferation (esp. Ti4+), and maturation (esp. Zr4+). The correlation reveals the negative effect of oxide thickness, esp. TiOx and TaOx on osteoblastogenesis. This study also shows that the characterisation of the chemical state and elemental electronic structure of the alloys' surface is more predictive than physical properties, namely SFE and roughness.

Possibilities of orthopedic technical care for extremity lengthening and reconstruction

Orthopedic technical care plays acrucial role in improving function and mobility for patients undergoing limb lengthening and reconstruction. The treatment strategy is based on aprecise classification of the defect, taking into account factors such as joint instability, muscle pathology and limb length discrepancy. The selection of orthopedic aids depends on the specific deformity, its classification and the individual needs of the patient. Through interdisciplinary decision-making and customized adaptations of prostheses and orthoses, optimal function and aesthetically pleasing outcomes can be achieved. The utilization of custom-made technical components, such as traction devices combined with elastic liners, is essential for long-term treatment success and can support surgical interventions. The treating physician's expertise is crucial in selecting the appropriate orthopedic technical device following limb lengthening and reconstruction.

An Integrative Computational Design Workflow and Validation Methodology for 3D-Printed Personalized Orthopedic Devices: Case Study of a Wrist–Hand Orthosis (WHO)

Additive manufacturing (AM) technologies enable the production of customized and personalized medical devices that facilitate users’ comfort and rehabilitation requirements according to their individual conditions. The concept of a tailor-made orthopedic device addresses the accelerated recovery and comfort of the patient through the utilization of personalized rehabilitation equipment. Direct modeling, with an increasing number of approaches and prototypes, has provided many successful results until now. The modeling procedure for 3D-printed orthoses has emerged as the execution of steady and continuous tasks with several design selection criteria, such as cutting, thickening the surface, and engraving the shell of the orthosis. This publication takes into consideration the aforementioned criteria and proposes the creation of a holistic methodology and automated computational design process for the customization of orthotic assistive devices, considering aspects such as material properties, manufacturing limitations, recycling, and patients’ requirements. This proposal leads to the designing and manufacturing of a wrist orthopedic device based on reverse engineering, Design for AM (DfAM), and Design for Recycling (DfR) principles. The proposed methodology can be adjusted for different limbs. A dual-material approach was attained utilizing rigid, mechanically enhanced feedstock material and soft elastic material with reduced skin irritation risks to achieve both mechanical requirements and adequate cushioning for user comfort during rehabilitation. Recyclable thermoplastic matrices were selected, which also allow for the option to create washable devices for product life extension. Then, 3D scanning procedures were implemented to acquire the initial anatomic measurements for the design of the WHO and ensure and assess the dimensional accuracy of the final product. Physical mechanical testing was implemented to evaluate the WHO’s mechanical behavior and verify its functionality during basic wrist movements. The extracted dimensional data for the two main orthosis components that indicated approximately 50% and 25% of the tolerance values, respectively, were within the range (−0.1 mm, 0.1 mm).

Combined First-Principles and Experimental Study on the Microstructure and Mechanical Characteristics of the Multicomponent Additive-Manufactured Ti-35Nb-7Zr-5Ta Alloy.

New β-stabilized Ti-based alloys are highly promising for bone implants, thanks in part to their low elasticity. The nature of this elasticity, however, is as yet unknown. We here present combined first-principles DFT calculations and experiments on the microstructure, structural stability, mechanical characteristics, and electronic structure to elucidate this origin. Our results suggest that the studied β Ti-35Nb-7Zr-5Ta wt % (TNZT) alloy manufactured by the electron-beam powder bed fusion (E-PBF) method has homogeneous mechanical properties (H = 2.01 ± 0.22 GPa and E = 69.48 ± 0.03 GPa) along the building direction, which is dictated by the crystallographic texture and microstructure morphologies. The analysis of the structural and electronic properties, as the main factors dominating the chemical bonding mechanism, indicates that TNZT has a mixture of strong metallic and weak covalent bonding. Our calculations demonstrate that the softening in the Cauchy pressure (C' = 98.00 GPa) and elastic constant C̅44 = 23.84 GPa is the origin of the low elasticity of TNZT. Moreover, the nature of this softening phenomenon can be related to the weakness of the second and third neighbor bonds in comparison with the first neighbor bonds in the TNZT. Thus, the obtained results indicate that a carefully designed TNZT alloy can be an excellent candidate for the manufacturing of orthopedic internal fixation devices. In addition, the current findings can be used as guidance not only for predicting the mechanical properties but also the nature of elastic characteristics of the newly developed alloys with yet unknown properties.

Approach for Non-Intrusive Detection of the Fit of Orthopaedic Devices Based on Vibrational Data.

The soft tissues of residual limb amputees are subject to large volume fluctuations over the course of a day. Volume fluctuations in residual limbs can lead to local pressure marks, causing discomfort, pain and rejection of prostheses. Existing methods for measuring interface stress encounter several limitations. A major problem is that the measurement instrumentation is applied in the sensitive interface between the prosthesis and residual limb. This paper presents the principle investigation of a non-intrusive technique to evaluate the fit of orthopaedic prosthesis sockets in transfemoral amputees based on experimentally obtained vibrational data. The proposed approach is based on changes in the dynamical behaviour detectable at the outer surface of prostheses; thus, the described interface is not affected. Based on the experimental investigations shown and the derived results, it can be concluded that structural dynamic measurements are a promising non-intrusive technique to evaluate the fit of orthopaedic prosthesis sockets in transfemoral amputee patients. The obtained resonance frequency changes of 2% are a good indicator of successful applicabilityas these changes can be detected without the need for complex measurement devices.

Orthotics and prosthetics by 3D-printing: Accelerating its fabrication flow

Orthoses and socket prostheses are rarely used orthopaedic devices in veterinary medicine. Recently, more pet owners have sought these treatments for pets with orthopaedic conditions. However, veterinarians often lack substantial scientific evidence on device outcomes and may expect high costs, the main limiting factor, if human orthopaedic market prices are assumed. This discrepancy creates an imbalance between pet owners' expectations, veterinarians' recommendations, and actual patient benefits. To address economic constraints and enhance knowledge about these devices, this study used 3D technology—namely 3D scanning and printing via fused deposition modelling—to design, modify, and manufacture orthoses and socket prostheses for ten patients, including nine dogs and one calf. An equation was devised and applied to all printed devices to streamline the resizing process for sockets and orthoses. The 3D-printed devices were fitted to the patients, and their adaptation was assessed using three novel scales based on prior scientific literature in the small animal orthopaedic field. The orthoses were well-tolerated, with successful and straightforward adaptation. Although socket prostheses were tolerated, the dogs' adaptation was suboptimal, while the calf demonstrated excellent and immediate adaptation.

The Prince’s Prosthetic Body: Orthopedic Armor and Material Self-Fashioning in Sixteenth-Century Europe

Commonly seen to display military prowess or chivalric virtue, parade armor of the sixteenth century here is considered for its impact on the wearer’s own physiology and psychology. Through juxtaposing the ergonomic features of muscle cuirasses and children’s harnesses with courtly etiquette rules, humanist educational regimes, and orthopedic devices in medicine, this paper reveals armor’s stakes in fashioning the princely body by means of physical discipline rather than visual representation. Plate armor, by “correcting” posture and mannering comportment, aided in molding an exemplary disposition expected to incite subjects to imitation.

1st EFORT European Consensus "Medical & Scientific Research Requirements for the Clinical Introduction of Artificial Joint Arthroplasty Devices": Background, Delphi Methodology & Consensus process.

The objectives of the 1st EFORT European Consensus on 'Medical and Scientific Research Requirements for the Clinical Introduction of Artificial Joint Arthroplasty Devices' were foremost to focus on patient safety by establishing performance requirements for medical devices. The 1st EFORT European Consensus applied an a priori-defined, modified Delphi methodology to produce unbiased, high-quality recommendation statements, confirmed by consensus voting of a European expert panel. Intended key outcomes are practical guidelines justified by the current stage of knowledge and based on a broad European Expert Consensus, to maintain innovation and optimisation of orthopaedic devices within the boundaries of MDR 2017/745. Twenty-one main research areas of relevance were defined relying on input from the EFORT IPSI WG1 'Introduction of Innovation' recommendations and a related survey. A modified Delphi approach with a preparatory literature review and work in small groups were used to prepare answers to the research questions in the form of 32 draft Consensus statements. A Consensus Conference in a hybrid format, on-site in the Carl Gustav Carus University of Dresden was organised to further refine the draft statements and define consensus within the complete group of participants by final voting, intended to further quantify expert opinion knowledge. The modified Delphi approach provides practical guidelines for hands-on orientation for orthopaedic surgeons, research institutes and laboratories, orthopaedic device manufacturers, patient representatives, Notified Bodies, National Institutes and authorities. For the first time, initiated by the EFORT IPSI (WG1 'Introduction of Innovation'), knowledge of all related stakeholders was combined in the 1st EFORT European Consensus to develop guidelines and result in a comprehensive set of recommendations.

Infection-responsive long-term antibacterial bone plates for open fracture therapy.

The infections in open fracture induce high morbidity worldwide. Thus, developing efficient anti-infective orthopedic devices is of great significance. In this work, we designed a kind of infection-responsive long-term antibacterial bone plates. Through a facile and flexible volatilization method, a multi-aldehyde polysaccharide derivative, oxidized sodium alginate, was crosslinked with multi-amino compounds, gentamycin and gelatin, to fabricate a uniform coating on Ti bone plates via Schiff base reaction, which was followed by a secondary crosslinking process by glutaraldehyde. The double-crosslinked coating was stable under normal condition, and could responsively release gentamycin by the triggering of the acidic microenvironment caused by bacterial metabolism, owning to the pH-responsiveness of imine structure. The thickness of the coating was ranging from 22.0μm to 63.6μm. The coated bone plates (Ti-GOGs) showed infection-triggered antibacterial properties (>99%) and high biocompatibility. After being soaked for five months, it still possessed efficient antibacterial ability, showing its sustainable antibacterial performance. The in vivo anti-infection ability was demonstrated by an animal model of infection after fracture fixation (IAFF). At the early stage of IAFF, Ti-GOGs could inhibit the bacterial infection (>99%). Subsequently, Ti-GOGs could promote recovery of fracture of IAFF. This work provides a convenient and universal strategy for fabrication of various antibacterial orthopedic devices, which is promising to prevent and treat IAFF.

Introduction of innovations in joint arthroplasty: Recommendations from the 'EFORT implant and patient safety initiative'.

With the implementation of the new MDR 2017/745 by the European Parliament, more robust clinical and pre-clinical data will be required due to a more stringent approval process. The EFORT Implant and Patient Safety Initiative WG1 'Introduction of Innovation', combined knowledge of orthopaedic surgeons, research institutes, orthopaedic device manufacturers, patient representatives and regulatory authorities to develop a comprehensive set of recommendations for the introduction of innovations in joint arthroplasty within the boundaries of MDR 2017/745. Recommendations have been developed to address key questions about pre-clinical and clinical requirements for the introduction of new implants and implant-related instrumentation with the participation of a steering group, invited by the EFORT Board in dialogue with representatives from European National Societies and Speciality Societies. Different degrees of novelty and innovation were described and agreed on in relation to when surgeons can start, using implants and implant-related instrumentation routinely. Before any clinical phase of a new implant, following the pre-market clinical investigation or the equivalent device PMCF pathway, it is a common understanding that all appropriate pre-clinical testing (regulatory mandatory and evident state of the art) - which has to be considered for a specific device - has been successfully completed. Once manufacturers receive the CE mark for a medical device, it can be used in patients routinely when a clinical investigation has been conducted to demonstrate the conformity of devices according to MDR Article 62 or full equivalence for the technical, biological and clinical characteristics has been demonstrated (MDR, Annex XIV, Part A, 3.) and a PMCF study has been initiated.