Orthopedic Devices Research Articles

Enriching in vivo clinical trials with in silico models for orthopedic implants

Clinical trials are used by the medical device industry to confirm products safety, performance, and clinical benefits. Traditional clinical studies typically follow a limited number of volunteers, which prevents capturing the full breath of patient demographics and implant use. New tools are required to overcome the limitations of traditional trials while fulfilling increasingly demanding regulatory requirements. Computer simulations have the potential to enrich traditional clinical trials with so called in silico clinical trials (ISCT) by providing data on a much broader spectrum of patients, clinical conditions and implant configurations. The historical use of simulation in the orthopedic device industry is described here to explain how it is now technically possible to model virtual populations. We also discuss the multiple benefits of such a translational research approach for the patients, healthcare systems, and manufacturers, but also the challenges to overcome. A more detailed version is available in English [1].

Translation of three-dimensional printing for orthopedic devices

Translation of three-dimensional printing for orthopedic devices

Complication after the reconstruction of the old patellar tendon rupture

Introduction. Chronic patellar tendon rupture (PTR) occurs rarely; its frequency and prevalence are unknown. There are very little data on the late patellar tendon reconstruction in rheumatoid arthritis and its complications. Case report. We presented a surgical repair of a PTR with early postoperative rupture of the contralateral patellar tendon for a 21-year-old woman with a past medical history of juvenile rheumatoid arthritis (treated with corticosteroids) who sustained initial injury 11 months prior to the presentation. The contralateral side was used for autograft harvesting. We used bone-tendon-bone (BTB) autograft and allografts followed by double-wire loop reinforcement and immediate postoperative mobilization. The patient was followed for 2 years, and the function of both knees was re-stored completely, with a full active range of motion. In this case, reconstruction of an 11-month-old chronic PTR (with complete resorption of the tendon and completely separated infrapatellar pads, complicated by the contralateral PTR) with BTB autograft and allografts and double wire loop reinforcement gave an excellent functional result. Two years after the surgical treatment, the extensor function of both knees was completely restored with a full range of movements. The patient reported satisfying outcomes and was able to return to all pre-injury activities without the assistance of orthopedic devices. Conclusion. This case report highlights the importance of the early diagnosis and describes operative techniques used in chronic PTR repair and treatments of the early postoperative complications such as rupture of the contralateral tendon.

The boon of nasoalveolar molding (NAM) treatment in early management of cleft lip and palate patients

Patients with different types of labio-maxillo-palatine clefts go through a lifelong series of multidisciplinary therapeutic procedures; this “journey” sometimes begins prenatally and extends into adulthood. Presurgical orthopedic treat­ment (PSO) is one of the first stages of this therapeutic plan. The nasoalveolar molding technique (NAM) is a new method of approach, from the field of pre-surgical or­tho­pe­dics, in­sti­tu­ted at a very young age (infant), and aims to reduce the initial severity, the level of alveolar cleft and/or the degree of nasal deformity. This approach enables the primary surgical restore of the nostril and lip to heal beneath minimum ten­sion, thereby reducing scar for­ma­tion and enhancing the esthetic result. The NAM tech­nique is the non-surgical, pas­sive method of bringing the gum and lip together by re­di­rec­ting natural growth forces. NAM has been shown to be an effective adjunctive the­ra­py for reducing pain, de­for­mity and the level of soft tissue tearing before surgery. This paper reviews the basic principles of NAM therapy, the different types of devices used in this therapy, the protocol followed and a critical eva­lua­tion of the advantages and disadvantages of this tech­nique. As an example, finally, we present the case of an infant with a unilateral labio-maxil­lary cleft, to which a NAM-type orthopedic device was applied with the aim of reducing tensions at the level of the tissues with the de­fect, to minimize the extent of the sur­gi­cal intervention and to minimize the risk of postsurgical re­trac­tile scars. World­wide, the authors of various studies agree on the positive out­come of NAM for better aesthetics after surgical repair of cleft lip and palate (DLP). However, what still remains, at this moment, unfounded equivocal is whether the pre-sur­gi­cal reduction of the cleft sizes and the modeling ma­ni­pu­la­tion of the nasal complex benefit our patients in the long term. Despite a relatively small amount of high-level evi­dence, NAM appears to be a promising technique that de­serves further research.

Gradient coil and radiofrequency induced heating of orthopaedic implants in MRI: influencing factors

Patients with implanted orthopaedic devices represent a growing number of subjects undergoing magnetic resonance imaging (MRI) scans each year. MRI safety labelling is required for all implants under the EU Medical Device Regulations to ensure regulatory compliance, with each device assessed through standardised testing procedures. In this paper, we employ parametric studies to assess a range of clinically relevant factors that cause tissue heating, performing simulations with both radiofrequency (RF) and gradient coil (GC) switching fields, the latter of which is often overlooked in the literature. A series of ‘worst-case’ scenarios for both types of excitation field is discussed. In the case of GC fields, large volume implants and large plate areas with the field orientated perpendicular to the plane cause the highest heating levels, along with sequences with high rates of field switching. Implant heating from RF fields is driven primarily from the ‘antenna effect’, with thin, linear implants of resonant length resulting in the highest temperature rises. In this work, we show that simplifications may be made to the field sequence and in some cases the device geometry without significantly compromising the accuracy of the simulation results, enabling the possibility for generic estimates of the implant heating for orthopaedic device manufacturers and opportunities to simplify the safety compliance process.

Polylactic acid/multi walled carbon nanotubes (PLA/MWCNT) nanocomposite for 3D printing of medical devices

In recent years, the composite nanomaterials area has had a great development impact in health sciences. Biomaterials depict as one of the most promising since they are compatible with additive manufacturing (AM) techniques. It is also possible to use them to mold specific medical parts. Composite nanomaterials have shown good biocompatibility and low toxicity to have benefits equal to or greater than metals (i.e., Co-Cr alloy). The purpose of this study is to develop a nanocomposite biomaterial (PLA/MWCNTf) from Polylactic Acid (PLA) and functionalized Multi Walled Carbon Nanotubes (MWCNTf) to evidence its potential application in 3D printing of orthopedic fixation devices. PLA/MWCNTf nanocomposite was prepared by solution blending technique, incorporating a proportion of 0.5 wt% of MWCNTf to the PLA matrix. TGA analysis of the PLA/MWCNTf was used to determine the thermal stability, a slight increase was found compared to the PLA. FTIR spectroscopy confirmed the presence of carboxylic acid groups in the MWCNTf which improves good incorporation of the nanotubes in the PLA matrix. Additionally, Raman spectroscopy, SEM, and AFM micrographs were used to verify MWCNTf reached the PLA surface homogeneously. Additive manufacturing preparation was done by extrusion molding of PLA/MWCNTf as well as its 3D printing.

Enfants handicapés abandonnés : quel profil dans une pouponnière en Côte d’Ivoire ?

The admission of children with disabilities to a dedicated nursery in Côte d’Ivoire has made it possible to respond to the fight against infanticide or neglect without care. The aim of this work was to define the profile of disabled children abandoned and admitted to the Dabou nursery in Côte d’Ivoire. Material and methodsDescriptive cross-sectional study carried out over a 9-month period in the Dabou nursery in Côte d’Ivoire and including 74 children and adolescents with disabilities. The epidemiological, clinical and functional data and the treatment needs of infants were described. ResultsChildren aged 0 to 3 and 6 to 10 years were the most numerous (45% of cases) with a predominance of males (sex ratio=1.31). They came mainly from the capital of the country. The infants’ clinical aspects were polymorphic, sometimes associated with limb malformations (68.9%), various motor impairments, neuro-orthopaedic deformities (59.46%), and psychomotor acquisition delays. The therapeutic needs expressed were varied and superimposed on the clinical aspects of the children and were broken down into rehabilitation activities, orthopaedic devices and care. ConclusionThe implementation of an adapted rehabilitation care strategy is necessary to support disabled children who have been abandoned and admitted to a dedicated nursery.

An Optoelectronics-Based Sensor for Measuring Multi-Axial Shear Stresses

There is an increasing need for tactile shear sensors, particularly for medical applications such as orthopedic rehabilitation. Examples include measuring interfacial shear stresses between a residual limb and prosthesis to monitor socket fit and improve residual limb tissue health, and tracking shearing between a foot and shoe for assessing performance in athletes. However, there are considerable challenges in implementing shear force sensors for orthopedic applications due to the requirements for noninvasiveness, low mass, low power, and robustness against motion artifacts, normal force, and/or electromagnetic fields. To address these challenges, we designed, fabricated, and characterized a simple, low-cost, optoelectronic sensor that can measure multi-axial shear stresses. This novel sensor is based on a red, green, and blue (RGB) light-emitting diode (LED) projecting a cyclic illumination of RGB light onto a color pattern surface. As shear strain causes a displacement between the LED and the color pattern, the intensities of the reflected lights change due to the shift of the color pattern position. A photodiode captures the reflected light intensity at each color illumination, allowing the determination of the color pattern surface displacement and the shear along two axes. In this paper, we also report the efficacy of the sensor under benchtop testing conditions, confirming the potential of this technology for shear monitoring in orthopedic devices such as protheses or shoes. Future efforts will focus on miniaturization and packaging of the sensors, and characterizing their performance for the aforementioned medical applications.

Posttraumatic Osteoarthritis. Effective Combination of Non-steroidal Anti-inflammatory Drugs and SYSADOA

Osteoarthritis (OA) is the most frequent joint desease and is the leading cause of the functional loss and disability among older patients. The heterogeneity of OA determines the absence of a 100% effective therapeutic strategy for all patients. In addition, this heterogeneity may be the main reason for the failure of clinical trials of therapeutic agents designed to restore cartilage. The SYSADOA group of drugs, in particular – glucasamine and chondroitin, is among the most studied compounds, have a good safety profile and showed proven efficacy in the early stages of osteoarthritis. The use of these drugs in combination with non-steroidal anti-inflammatory drugs (NSAIDs) is widespread in the world and is included in the recommendations of the European Society for Clinical and Economic Aspects of Osteoporosis and Osteoarthritis – ESCEO. The objective: to assess the clinical efficacy and safety of the combination of diclofenac potassium 50 mg, chondroitini sulfatis 400 mg and glucosamini sulfatis 500 mg; chondroitini sulfatis 400 mg and glucosamini sulfatis 500 mg in treatment of patients with knee and ankle post-traumatic osteoarthritis in the early stages (I–II according to Kelgren and Lawrence). Materials and methods. The study was designed as a randomized comparative prospective placebo-controlled in parallel groups. The level of evidence for this study is II-B. Patients of the main group N1 underwent surgical treatment for joint trauma and had a radiographically and clinically confirmed diagnosis: post-traumatic osteoarthritis stage I-II (according to Kelgren and Lawrence) of the ankle (N1.1=15) and knee (N1.2=15) joints. Time from injury and surgery was 14.3±2.3 months. Patients from main group received combination of diclofenac potassium, chondroitini sulfatis and glucosamini sulfatis for 10 days at the begining of the treatment course, and followed with combination of chondroitin and glucosamin for 3 months further. The comparison group included similar patients in terms of the number, gender, age and the nature of OA (N2.1=15; N2.2=15), these patients were prescribed diclofenac potassium 50 mg 2 times a day (for the first 10 days of treatment), and further followed with placebo (for the next 3 months). All enrolled patients also were prescribed basic non-pharmacological treatment, which included body weight control, physical therapy, mechanotherapy, exercises, together with orthopedic devices to unload and stabilize the affected joint. The results of treatment were assessed clinically at 3 months and 6 months after the start of treatment using VAS, functional state of the ankle (according to AOFAS) and knee (according to Lysholm scale); on each visit information about adverse reactions was collected. Results. After 3 months, the intensity of pain according to VAS in the N1.1 group was 24.8±2.1 points, and in the N2.1 group 29.2±3.2 (p<0.05). After 6 months, the VAS results were accordingly 15.1±3.4 vs 26.7±0.9 (p<0.01). The functional capacity of the ankle joint, evaluated by AOFAS, after 3 months in N1.1 group achieved 81.7±4.3 and 68.4±5.6 points in N2.1 group (p<0.01). At 6 months, the AOFAS score was 93.9±3.8 vs 79.4±4.1 (p<0.05). After 3 months VAS score in patients with early stages of knee OA (group N1.2 and N2.2) was 21.2±1.9 vs 28.3±3.1 mm (p<0.05); after 6 months – 14.7±1.4 vs 23.9±2.8 mm (p<0.01). The level of functional activity after 3 months of treatment according to the Lysholm scale achieved 86.8±2.9 points versus 68.4±5.6 points (p<0.05) and after 6 months - continued to grow and got to 97.4±1.2 vs 86.2±2.9 points (p<0.01). There were no statistical differences in number and intensity of the adverse events in the studied groups (p>0.5). Conclusions. In the early stages of post-traumatic osteoarthritis of the knee and ankle joints (I–II according to Kelgren and Lawrence), a 3-month course of treatment with combination of NSAID and SYSADOA (diclofenac with chondroitin and glucosamin), followed by further treatment with SYSADOA (chondroitin and glucosamine) demonstrated superior efficacy compared to the placebo/standard treatment with the same level of safety.

Cutibacterium acnes clonal complexes display various growth rates in blood culture vials used for diagnosing orthopedic device-related infections

ObjectivesBlood culture bottles (BCBs) are commonly used for the diagnosis of infections associated with orthopedic devices. Although Cutibacterium acnes is an important pathogen in orthopedics, relatively little is known about its growth characteristics in BCBs. This prompted us to analyze the influence of bacterial genotype and clinical significance on time-to-detection (TTD) in BCBs. MethodsWe reviewed 59 cases of orthopedic device-related infections in which at least one intraoperative specimen yielded a pure C. acnes culture from anaerobic BCBs (BD Bactec Lytic/10 Anaerobic/F; Lytic-Ana) and/or solid media. A strain was considered infectant if the same genotype was present in two or more intraoperative samples. From these cases, we isolated a total of 72 unique C. acnes strains belonging to four multilocus sequence type clonal complexes (CCs): CC18, CC28, CC36 and CC53. Growth rate and TTD in Lytic-Ana BCB were studied under experimental conditions (inoculation of standard inoculum) and in clinical samples (inoculation of periprosthetic tissue samples). ResultsMedian TTD values were shorter for CC53 compared to other CCs under experimental conditions (69 vs. 103 h; p < 0.001) and from clinical specimens (70 vs. 200 h; p = 0.02). Infectant strains had a shorter median TTD compared to contaminant strains in a clinical situation, while the difference was not observed under experimental conditions. ConclusionsThe detection dynamics of C. acnes in Lytic-Ana BCBs were associated with genotype. Thus, TTD not only reflects the bacterial load in clinical samples, but may also reflect the intrinsic properties of the clonal complex of C. acnes.

Physiopathologie des infections ostéoarticulaires

Bone and joint infections gather heterogeneous clinical situation according to the infected site, the presence of orthopedic device and the infection chronicity. Their pathophysiology implicates complex interactions between the infectious agent, host immune system and osteoarticular tissue. It involves virulence factors at the initial phase of tissue invasion and destruction, and persistence mechanisms leading to chronicity and relapse. Infection can arise from three different pathways: direct inoculation during and invasive procedure or an open trauma, extension of a contiguous infection, or hematogenous spread during a bacteremia. Then, bacteria adhesion and the initial development of infection induces an inflammatory response that unbalances bone homeostasis resulting in bone lysis. Conversely, persistence mechanisms allow bacterial escape from the host immune system and the action of most antimicrobials. They include: (i) biofilm formation, a bacterial community adherent to the osteoarticular tissue and/or orthopedic device and organized in a self-produced matrix, that regulates bacterial survival in hostile growth conditions; (ii) bacterial internalization and persistence within bone cells constituting intracellular reservoirs; and (iii) phenotype switching to small colony variants characterized by a reduced metabolism and a tolerance to antimicrobials.

Minimum performance level definition for bone plate testing according to standard: A preliminary study

In silico modeling of osteosynthesis medical devices allows the reduction of the time required for experimental tests and the introduction of “simulation-driven design”. Using a wise combination of these techniques and analytical calculations, it is possible to relate the experimental results, which are mandatory for regulatory purposes, to the plate physiological application and prevent the occurrence of complications in the early stages after the orthopedic device implantation on humans and animals.

Minimum performance level definition for bone plate testing according to standard: A preliminary study

In silico modeling of osteosynthesis medical devices allows the reduction of the time required for experimental tests and the introduction of “simulation-driven design”. Using a wise combination of these techniques and analytical calculations, it is possible to relate the experimental results, which are mandatory for regulatory purposes, to the plate physiological application and prevent the occurrence of complications in the early stages after the orthopedic device implantation on humans and animals.

The effects of orthopedic pathological conditions and systemic diseases on the prevalence of hip osteoarthritis in Modern African- and European-Americans.

Osteoarthritis (OA) is a leading cause of disability among aging adults. In the U.S., many individuals living with total hip replacements attribute OA as the cause. However, the majority of anthropological OA research excludes pathological individuals (i.e., individuals with systemic disease, traumatic injuries, or orthopedic devices). Thus, little is known about how implants and pathological conditions impact OA beyond a general acceptance that they likely increase OA risk. This study adds to the skeletal research surrounding OA by directly investigating its relationship with age, disease, and implants. The proximal femora of 186 African- and European-American individuals (21-95 years old) from the Edmonds Orthopedic Pathology Collection (National Museum of Health and Medicine; Armed Forces Institute of Pathology) were analyzed. The individuals were grouped into three cohorts: disease; non-disease; and previous injury/implant. Jurmain's (1990) ordinal scoring method was used to categorize OA changes as: none/slight; moderate; severe; and ankylosis. Intra-rater reliability for the scoring of OA was perfect, while inter-rater reliability was moderate. Results from Chi-square tests, exploratory data analysis, and ordinal logistic regression showed that there was a statistically significant relationship (p < 0.001) between degree of OA, age, recorded disease (e.g., cancer), and evidence of previous injury (i.e., healed fractures, fracture fixation devices). In contrast with the expectation that different populations exhibit different patterns of OA, no significant sex or ancestry effects were observed. These results help researchers better understand the etiology and contemporary risk factors of OA as well as identifying an additional subset of the population who may be at greater risk for developing OA - i.e., individuals with fractures, implants, and systemic disease, especially those in older age cohorts (60+ years).

Prevalence of complementary and alternative medicine despite limited perceived efficacy in patients with rheumatic diseases in Mexico: Cross-sectional study.

Complementary and alternative medicine (CAM) is frequently used by patients with rheumatic diseases (RD) to improve their symptoms; however, its diversity and availability have increased notably while scientific support for its effectiveness and adverse effects is still scarce. To describe the prevalence and diversity of CAM in patients with RD in Chihuahua, Mexico. A cross-sectional study was conducted in 500 patients with RD who were interviewed about the use of CAM to treat their disease. The interview included sociodemographic aspects, characteristics of the disease, as well as a description of CAM use, including type, frequency of use, perception of the benefit, communication with the rheumatologist, among others. The prevalence of CAM use was reported by 59.2% of patients, which informed a total of 155 different therapies. The herbal CAM group was the most used (31.4%) and included more than 50 different therapies. The use of menthol-based and arnica ointments was highly prevalent (35%). Most patients (62.3%) reported very little or no improvement in their symptoms. Only a fourth of the patients informed the rheumatologist of the use of CAM. The use of CAM was influenced by female sex, university degree, diagnosis delay, lack adherence to the rheumatologist's treatment, family history of RD, and orthopedic devices. The use of CAM in our population is highly prevalent and similar to reports in different populations suggesting a widespread use in many different societies. We found high use of herbal remedies; however, there were many different types suggesting a lack of significant effect. Patients continue using CAM despite a perception of no-effectiveness. Recurrent use of CAM is explained by factors other than its efficacy.

Biodegradable magnesium alloys for orthopaedic applications.

ABSTRACTThere is increasing interest in the development of bone repair materials for biomedical applications. Magnesium (Mg)-based alloys have a natural ability to biodegrade because they corrode in aqueous media; they are thus promising materials for orthopaedic device applications in that the need for a secondary surgical operation to remove the implant can be eliminated. Notably, Mg has superior biocompatibility because Mg is found in the human body in abundance. Moreover, Mg alloys have a low elastic modulus, close to that of natural bone, which limits stress shielding. However, there are still some challenges for Mg-based fracture fixation. The degradation of Mg alloys in biological fluids can be too rapid, resulting in a loss of mechanical integrity before complete healing of the bone fracture. In order to achieve an appropriate combination of bio-corrosion and mechanical performance, the microstructure needs to be tailored properly by appropriate alloy design, as well as the use of strengthening processes and manufacturing techniques. This review covers the evolution, current strategies and future perspectives of Mg-based orthopaedic implants.

Update on the research and development of magnesium-based biodegradable implants and their clinical translation in orthopaedics.

ABSTRACTBiodegradable magnesium (Mg) or its alloys are desirable materials for development into new-generation internal fixation devices or implants with high biocompatibility, adequate mechanical modulus, and osteopromotive properties, which may overcome some of the drawbacks of the existing permanent orthopaedic implants with regard to stress-shielding of bone and beam-hardening effects on radiographic images. This review summarises the current research status of Mg-based orthopaedic implants in animals and clinical trials. First, detailed information of animal studies including bone fracture repair and anterior cruciate ligament reconstruction with the use of Mg-based orthopaedic devices is introduced. Second, the repair mechanisms of the Mg-based orthopaedic implants are also reviewed. Afterwards, reports of recent clinical cases treated using Mg-based implants in orthopaedics are summarised. Finally, the challenges and the strategies of the use of Mg-based orthopaedic implants are discussed. Taken together, the collected efforts in basic research, translational work, and clinical applications of Mg-based orthopaedic implants over the last decades greatly contribute to the development of a new generation of biodegradable metals used for the design of innovative implants for better treatment of orthopaedic conditions in patients with challenging skeletal disorders or injuries.

A few words about the arthrodesis operation

The operation of arthrodesis, or artificial ankylosis of the joint, first performed by Albert in 1878, is one of the most beneficial orthopedic methods of treatment in cases of complete paralysis of all muscles moving this joint and in cases of ankylosis in a functionally disadvantageous position of the joint, when a quick recovery of the patient's ability to work is required if it is impossible, for one reason or another, to use his orthopedic devices.

Biocompatibility assessment of biomaterials used in orthopedic devices: An overview (Review).

Biocompatibility is one of the mandatory requirements for the clinical use of biomaterials in orthopedics. It refers to the ability of a biomaterial to perform its function without eliciting toxic or injurious effects on biological systems but producing an appropriate host response in a specific case. Today, the biocompatibility concept includes not only bio-inertia, but also biofunctionality and biostability. High biocompatibility and functional properties are highly desirable for new biomaterials. The chemical, mechanical, structural properties of biomaterials, their interaction with biological environment or even the methodology of assessment can influence the biocompatibility. The biological evaluation of biomaterials includes a broad spectrum of in vitro and in vivo tests related to the cytocompatibility, genotoxicity, sensitization, irritation, acute and chronic toxicity, hemocompatibility, reproductive and developmental toxicitity, carcinogenicity, implantation and degradation as specified in different international standards. A brief review of the main assays used in the biocompatibility testing of orthopedic biomaterials is presented. In addition, their main biocompatibility issues are overviewed.

Antennifying Orthopedic Bone-Plate Fixtures for the Wireless Monitoring of Local Deep Infections

Infection is the unavoidable threat to any orthopedic implant that can also force its removal as extreme remedy. The diagnosis of infections is currently achieved by time consuming imaging (X-Rays, MRI, CT) or just by the onset of the patient's pain, when the problem is in an advanced status. Instead, by equipping the prosthesis with a local sensor (for the temperature as a first) and with a wireless communication radio, an early-time identification of the infection could be achieved. This paper proposes a method to transform an orthopedic device provided with holes (like a bone fixation plate) into an harvesting antenna integrating an RFID sensor, with no battery onboard. A miniaturized antenna adapter, fully embedded into a free hole, with tuning capability, collects the electromagnetic power intercepted by the medical device and transfers it to the RFID circuit. Simulations and experimentations with several prototypes demonstrated that the augmented implanted device can establish a stable RFID link up to 0.5 m and that it is able to correctly sample the variation (37°C - 40°C) of the local temperature of the bone as in case of typical deep infections.