Metal hypersensitivity in patients with orthopaedic implant complications-A retrospective clinical study

Metal implant allergy: A retrospective cohort analysis at a university allergy practice

Background: Concern of metal sensitization in pre- and postsurgical evaluation is growing, with the recent guidelines remaining the criterion standard for consideration of patch testing. Information remains scarce on surgical screening in the groups of patients who reported a history of metal sensitivity versus those with no reported history. Objective: The objective of this study was to assess the utility of patch testing in surgical candidates based on reported metal allergy history. The secondary objective was to evaluate the utility and outcomes in postsurgical patch testing. Methods: Nine hundred and thirty-one patient charts of patients with the diagnosis of "contact dermatitis" who underwent an evaluation at a single allergy clinic site between January 2013 and December 2022 were identified and reviewed as part of a retrospective chart review study. Patients were included in subgroups based on the time of patch testing and history of reported metal allergy. Results: In all, 67 patients underwent patch testing, 10 (14.9%) of whom were surgical candidates without a history of metal sensitivity, 31 (46.2%) of whom were surgical candidates with a history of metal sensitivity, and 26 (38.8%) of whom were postsurgical patients. Twenty-nine (43.3%) of patients had positive patch testing results, with only one (10%) in the presurgical group, 17 (54.8%) in the presurgical with a history of metal sensitivity, and 11 (42.3%) in the postsurgical group. Zero patients in our cohort without metal sensitivity who were undergoing the Nuss procedure had positive reactions on patch testing, whereas two of four (50%) with reported metal sensitivity who were undergoing the Nuss procedure had positive relevant metal reactions. Conclusion: Ambiguity in the utility of patch testing for surgical decision making remains, despite common utilization. Recent guidelines along with coordination of care among the surgeon, allergist, and patient remains the criterion standard of care.

Understanding immune-mediated cobalt/chromium allergy to orthopaedic implants: a meta-synthetic review

BACKGROUND

The frequency of primary joint replacement surgery continues to increase worldwide. While largely considered biologically inert entities, an increasing body of evidence continues to validate a not insignificant incidence of allergic reactions to such implants. Little previous work has explored genuinely immune-mediated reactivity in this context. In the absence of a contemporary published summary on the topic, this paper explored the current state of understanding of cobalt/chromium allergy and proposes a patient management algorithm whereby such immune reactions are clinically suggested.

METHODS

A structured, systematic literature review was performed by following PRISMA search principles to provide an updated review of this area.

RESULTS

Thirty-six topic-related articles were identified, the majority reflecting lower tiers of scientific evidence with a lack of homogeneous quantitative data to facilitate valid cohort comparisons. Largely, the available literature represented small case series' or expert opinions.

CONCLUSIONS

Despite increasing clinical awareness and acknowledgement of true allergy to joint replacement components, this review highlighted that the evidence base underpinning the diagnosis and management of such patients is limited. Both patient-reported metal allergy or skin patch testing are grossly unreliable methods and show almost no correlation with true immune reactivity. Recent studies suggested a potential role for patient-specific in vitro cellular activation testing and/or targeted genetic testing when cobalt/chromium allergy is clinically suspected. However, while likely representing the contemporary "best available" approaches both can be costly undertakings, are not yet universally available, and still require broader validation in non-research settings before wider uptake can be championed.

Emerging factors affecting peri-implant bone metabolism

Implant dentistry has evolved to the point that standard implant osseointegration is predictable. This is attributed in part to the advancements in material sciences that have led toward improvements in implant surface technology and characteristics. Nonetheless, there remain several cases where implant therapy fails (specifically at early time points), most commonly attributed to factors affecting bone metabolism. Among these patients, smokers are known to have impaired bone metabolism and thus be subject to higher risks of early implant failure and/or late complications related to the stability of the peri-implant bone and mucosal tissues. Notably, however, emerging data have unveiled other critical factors affecting osseointegration, namely, those related to the metabolism of bone tissues. The aim of this review is to shed light on the effects of implant-related factors, like implant surface or titanium particle release; surgical-related factors, like osseodensification or implanted biomaterials; various drugs, like selective serotonin reuptake inhibitors, proton pump inhibitors, anti-hypertensives, nonsteroidal anti-inflammatory medication, and statins, and host-related factors, like smoking, diet, and metabolic syndrome on bone metabolism, and aseptic peri-implant bone loss. Despite the infectious nature of peri-implant biological complications, these factors must be surveyed for the effective prevention and management of peri-implantitis.

Corrosion Resistance of 3D Printed Ti6Al4V Gyroid Lattices with Varying Porosity

Corrosion of medical implants is a possible failure mode via induced local inflammatory effects, systemic deposition and corrosion related mechanical failure. Cyclic potentiodynamic polarisation (CPP) testing was utilized to evaluate the effect of increased porosity (60% and 80%) and decreased wall thickness in gyroid lattice structures on the electrochemical behaviour of LPBF Ti6Al4V structures. The use of CPP allowed for the landmarks of breakdown potential, resting potential and vertex potential to be analysed, as well as facilitating the construction of Tafel plots and qualitative Goldberg analysis. The results indicated that 60% gyroid samples were most susceptible to the onset of pitting corrosion when compared to 80% gyroid and solid samples. This was shown through decreased breakdown and vertex potentials and were found to correlate to increased lattice surface area to void volume ratio. Tafel plots indicated that despite the earlier onset of pitting corrosion, both gyroid test groups displayed lower rates of corrosion per year, indicating a lower severity of corrosion. This study highlighted inherent tradeoffs between lattice optimisation and corrosion behaviour with a potential parabolic link between void volume, surface area and corrosion being identified. This potential link is supported by 60% gyroid samples having the lowest breakdown potentials, but investigation into other porosity ranges is suggested to support the hypothesis. All 3D printed materials studied here showed breakdown potentials higher than ASTM F2129's suggestion of 800 mV for evaluation within the physiological environment, indicating that under static conditions pitting and crevice corrosion should not initiate within the body.

Metal Hypersensitivity or Missed Periprosthetic Joint Infection? A Critical Review

The World Association Against Infection in Orthopedics And Trauma (W.A.I.O.T.) Study Group on Bone And Joint Infection Definitions Metal hypersensitivity (MHS) has been investigated by several authors as a possible reason for painful total joint arthroplasty, with controversial results. Periprosthetic joint infection (PJI) is another possible source of unexplained pain and implant failure that may be difficult to diagnose if not properly investigated. We performed this critical review to assess whether the current literature on MHS includes an adequate diagnostic workup to discern metal allergy from PJI. The results of this review highlight the importance of assessing patients for PJI before making a diagnosis of MHS and emphasize that the methods currently used to exclude PJI are substantially inadequate. Therefore, well-designed clinical trials with adequate diagnostic protocols and definitions of PJI that can differentiate MHS from low-grade PJI are needed. [Orthopedics. 2022;45(2):e73-e78.].

Titanium Allergy Caused by Dental Implants: A Systematic Literature Review and Case Report

(1) Background: Hypersensitivity reactions to metals may arise in predisposed patients chronically exposed to metallic materials, including dental implants made of titanium alloys. The purpose of this article was to systematically review titanium allergy manifestations in patients treated with dental implants and report a clinical case; (2) Methods: A systematic electronic search was performed for articles published in the English language until July 2021. The following eligibility criteria were adopted: (1) Population: individuals undergoing titanium and/or titanium alloy implant-supported rehabilitations; (2) Exposure: peri-implant soft tissue reactions attributable to implant insertion; (3) Outcome: evidence of titanium allergy, diagnostic methods, and forms of resolution; (3) Results: The included studies, in summary, presented evidence that titanium should not be considered an inert material, being able to trigger allergic reactions, and may be responsible for implant failure. A 55-year-old male patient received 3 implants in the posterior region of the left mandible and presented an epulis-like lesion developed from the peri-implant mucosa. The immunohistochemical analysis of the biopsy specimen confirmed the initial diagnosis of allergic reaction to titanium; (4) Conclusions: Although the evidence is weak, and titanium allergy has a low incidence, hypersensitivity reactions should not be underestimated. A rapid and conclusive diagnosis is mandatory to prevent further complications.

Patch Test Results and Outcome in Patients with Complications from Total Knee Arthroplasty: A Consecutive Case Series

The role of hypersensitivity in implant-related complications remains controversial. The objectives of our study were to (1) establish the prevalence of hypersensitivity to components of knee prostheses in patients referred to our contact dermatitis clinic, (2) determine if patients with post-surgery dermatitis have become sensitized, and (3) describe the outcome of patients with and without hypersensitivity. We reviewed the charts of patients referred from 2007 to 2018 and extracted demographic information, date, type, and site of implant, clinical presentation, and results of patch testing (PT) or lymphocyte transformation tests (LTT). We called most patients to gather data such as clinical outcome, nature, and timing of additional surgery. Statistical analysis included computation of conventional descriptive statistics. Because of the type of study design, only some categorical variables were tested for possible associations by analytical tools (cross-tabulation). Thirty-nine patients, 23 men (59.0%), and 16 women (41.0%), were included. Their mean age in years was 63.3 (95% confidence interval [CI]: 60.9-65.7) ranging from 39.0 to 79.0, (standard deviation) = 9.69, without statistically significant differences between males and females. Five patients had positive PT possibly relevant to their implant. Four patients had revision surgery and two improved. Of nine patients with dermatitis, one with relevant PT did not improve after revision, and the dermatitis was unrelated to TKA in eight. Of the 26 patients without dermatitis or relevant PT results, 9 had revisions because of incapacitating symptoms, and 5 improved. Hypersensitivity to implant components is a potential factor in the etiology of TKA complications. Patients with confirmed hypersensitivity may benefit from revision. Our study, however, did not detect statistically significant differences in outcome of revision surgery between patients with positive versus negative PT or LTT. In spite of this, we consider that patients with a history suggestive of metal, acrylate or aminoglycoside allergy should be tested preoperatively to avoid hypersensitivity-related postoperative complications. In the absence of hypersensitivity, some patients with incapacitating symptoms may also improve following revision.

Preclinical In Vitro Assessment of Submicron-Scale Laser Surface Texturing on Ti6Al4V

Loosening of orthodontic and orthopedic implants is a critical and common clinical problem. To minimize the numbers of revision surgeries due to peri-implant inflammation or insufficient osseointegration, developments of new implant manufacturing strategies are indicated. Ultrafast laser surface texturing is a promising contact-free technology to modify the physicochemical properties of surfaces toward an anti-infectious functionalization. This work aims to texture Ti6Al4V surfaces with ultraviolet (UV) and green (GR) radiation for the manufacturing of laser-induced periodic surface structures (LIPSS). The assessment of these surface modifications addresses key aspects of topography, morphology and chemical composition. Human primary mesenchymal stromal cells (hMSCs) were cultured on laser-textured and polished Ti6Al4V to characterize the surfaces in terms of their in vitro biocompatibility, cytotoxicity, and metal release. The outcomes of the in vitro experiment show the successful culture of hMSCs on textured Ti6Al4V surfaces developed within this work. Cells cultured on LIPSS surfaces were not compromised in terms of their viability if compared to polished surfaces. Yet, the hMSC culture on UV-LIPSS show significantly lower lactate dehydrogenase and titanium release into the supernatant compared to polished. Thus, the presented surface modification can be a promising approach for future applications in orthodontics and orthopedics.

A rare case of delayed hypersensitivity reaction to metal ions secondary to a remnant pedicle screw fragment after spinal arthrodesis

Delayed hypersensitivity reaction to metal ions is rare and has been mostly documented among patients undergoing total joint arthroplasty with metal-on-metal bearing surfaces. Nonetheless, to our knowledge, only a few cases associated with spinal arthrodesis have been reported in the literature. The aim of this case report was to describe the clinical features of a rare case of delayed-type hypersensitivity reaction to nickel that occurred after an extraordinarily long period of time (approximately 15 years) after spinal arthrodesis. Here, we present a 38-year-old patient who was referred to us with a diagnosis of delayed-type hypersensitivity reaction to nickel that was established by a skin patch test. The chief sign and symptoms of the patient were allergic contact dermatitis along with intractable, generalized itching that started several months ago. The medical history revealed that the patient had undergone spinal arthrodesis using rods and pedicle screws approximately 15 years ago, followed by revision surgery to remove the implants. Radiological examination showed a remnant pedicle screw fragment at the third lumbar vertebra that had broken off during the removal of implants nine years ago. However, the signs and symptoms of metal hypersensitivity started shortly before the patient was referred to our hospital. We decided to remove the screw fragment as allergic contact dermatitis was refractory to medical treatment. On postoperative day one, the itching was completely resolved, although the skin patch test remained positive.

Contact Allergy-Emerging Allergens and Public Health Impact

Contact allergy (sensitisation) and allergic contact dermatitis (ACD) resulting from it have a considerable public health impact. For the present review, all pertinent articles were systematically searched via Medline and Web of Science™; additionally, all available issues of the journals "Contact Dermatitis" and "Dermatitis" were manually searched, covering the years 2018-2019, thereby extending and re-focusing a previous similar review. New allergens, or previously described allergens found in a new exposure context or of other current importance, are described in sections according to substance classes, e.g., metals, preservatives, fragrances. As a common finding in many investigations, a lack of information on product composition has been noted, for instance, regarding a newly described allergen in canvas shoes (dimethylthiocarbamylbenzothiazole sulfide) and, most notably, absence of co-operation from manufacturers of glucose-monitoring devices and insulin pumps, respectively. These latter devices have been shown to cause severe ACD in a considerable number of diabetic patients caused by the liberation of isobornyl acrylate and N,N'-dimethylacrylamide, respectively, as demonstrated by an international collaboration between dermatologists and chemists. Improved and complete ingredient labelling for all types of products, and not just cosmetics, must be put on the legislative agenda.

General review of titanium toxicity

Background

Titanium is a commonly used inert bio-implant material within the medical and dental fields. Although the use of titanium is thought to be safe with a high success rate, in some cases, there are rare reports of problems caused by titanium. In most of these problematic reports, only individual reports are dominant and comprehensive reporting has not been performed. This comprehensive article has been prepared to review the toxicity of titanium materials within the medical and dental fields.

Methods

We used online searching tools including MEDLINE (PubMed), Embase, Cochrane Library, and Google Scholar by combining keywords such as “titanium implant toxicity,” “titanium implant corrosion,” “titanium implant allergy,” and “yellow nail syndrome.” Recently updated data has been collected and compiled into one of four categories: “the toxicity of titanium,” “the toxicity of titanium alloys,” “the toxicity of titanium implants,” and “diseases related to titanium.”

Results

Recent studies with regard to titanium toxicity have been increasing and have now expanded to the medical field in addition to the fields of environmental research and basic science. Problems that may arise in titanium-based dental implants include the generation of titanium and titanium alloy particles and ions deposited into surrounding tissues due to the corrosion and wear of implants, resulting in bone loss due to inflammatory reactions, which may lead to osseointegration failure of the dental implant. These titanium ions and particles are systemically deposited and can lead to toxic reactions in other tissues such as yellow nail syndrome. Additionally, implant failure and allergic reactions can occur due to hypersensitivity reactions. Zirconia implants can be considered as an alternative; however, limitations still exist due to a lack of long-term clinical data.

Conclusions

Clinicians should pay attention to the use of titanium dental implants and need to be aware of the problems that may arise from the use of titanium implants and should be able to diagnose them, in spite of very rare occurrence. Within the limitation of this study, it was suggested that we should be aware the rare problems of titanium toxicity.