Do E-cigarettes and vaping have a lower risk of osteoporosis, nonunion, and infection than tobacco smoking?

Non-Tobacco Nicotine Use and Complications in Free Flap Repair in Head and Neck Cancer

OBJECTIVE

Assess associations between non-tobacco nicotine usage and free flap repair complications in head and neck cancer (HNC) patients.

STUDY DESIGN

Propensity-matched retrospective cohort study.

METHODS

The TriNetX database was queried for HNC patients who underwent free flap procedures from 2010 to 2024. Among these patients, the NIC cohort was defined as those with dependence on nicotine prior to surgery, but without the use of cigarettes, chewing tobacco, or other tobacco products. The non-NIC cohort was defined as patients with no nicotine dependence, cigarettes, chewing tobacco, or other tobacco product use prior to surgery. Cohorts were propensity-matched based on demographics and comorbidities. Primary outcomes included free flap failure, blood vessel repair, and other revisionary procedures (associated with wound disruption or repair) within 30 days of the primary reconstruction. Secondary outcomes included infection, pneumonia, cardiopulmonary complications, and hematoma within 30 days.

RESULTS

Following propensity matching, 1324 patients were included in each cohort. Across all free flaps, non-tobacco nicotine use was associated with a significantly increased risk of other revision procedures (RR: 1.230 [95% CI: 1.013, 1.493], p = 0.036), sepsis (RR: 1.563 [95% CI: 1.009, 2.419], p = 0.045), fistula (RR: 1.588 [95% CI: 1.041, 2.423], p = 0.032), cardiovascular complications (RR: 1.420 [95% CI: 1.054, 1.914], p = 0.021), pneumonia (RR: 2.055 [95% CI: 1.570, 2.689], p < 0.001), and pulmonary embolism (RR: 2.220 [95% CI: 1.217, 3.933], p = 0.008).

CONCLUSIONS

Non-tobacco nicotine use is associated with an increased risk of postoperative complications in HNC patients following free flap reconstruction. Screening for non-tobacco nicotine use in surgical candidates may better inform clinical management and counseling.

LEVEL OF EVIDENCE

III.

The impact of electronic cigarettes on the outcomes of total joint arthroplasty

BACKGROUND

Cigarette smoking is known to result in poorer outcomes for patients undergoing total joint arthroplasty. Smoking tobacco cigarettes in the perioperative period is associated with higher analgesia usage, increased mortality, poorer healing, and an increased risk of medical complications. As such, many surgeons advise their patients not to smoke in the perioperative period. Electronic cigarettes are emerging as a popular alternative for usage by patients who would otherwise continue to smoke traditional cigarettes. Importantly, there has been limited investigation into the impact of electronic cigarette usage on the outcomes of total joint arthroplasty. This review investigates the potential detrimental effects caused by the usage of electronic cigarettes on the outcomes of total joint arthroplasty.

METHODS

A systematic review was carried out in accordance with the PRISMA Guidelines. We have drawn from studies that investigated the impact of the constituents of E-cigarette vapour on bone health, wound healing, the immune system and the direct impact of electronic cigarette usage on surgical outcomes.

RESULTS

Electronic cigarettes release nicotine in an inconsistent manner, resulting in many negative consequences for bone health. Furthermore, they depress the immune system, impair wound healing and may result in longer hospital stays.

CONCLUSIONS

Electronic cigarette usage should be monitored in the perioperative period to reduce the risk of complication. There is a pressing need for more comprehensive research in this area to fully understand the implications of EC usage on the outcomes of total joint arthroplasty.

Non-Tobacco Nicotine dependence associated with increased Postoperative Complications following Intramedullary Nailing for Intertrochanteric Femur Fractures

Objectives

Nicotine usage is known to increase postoperative complications; however, studies show that the general population believes that non-tobacco nicotine delivery devices are a safer option compared to tobacco-based nicotine products. This study evaluates postoperative complications between non-tobacco nicotine dependent and non-nicotine dependent patients for intramedullary nailing in intertrochanteric femur fractures.

Methods

Utilizing the TriNetX database, we retrospectively examined postoperative outcomes in patients aged 18 to 90 who underwent intramedullary nailing for intertrochanteric femur fractures between November 21, 2013, and November 21, 2023. Two cohorts were analyzed: Cohort A comprised nicotine-dependent patients without tobacco product usage (e.g. cigarettes or chewing tobacco) and Cohort B consisted of patients without any nicotine dependence. Propensity matching was performed for BMI, type 2 diabetes, alcohol/substance abuse, socioeconomic status, and demographic factors. Outcomes assessed included mortality, sepsis, pneumonia, revision, dehiscence, pulmonary embolism, nonunion, and deep vein thrombosis within 1 day to 6 months post-treatment.

Results

A total of 2,041 non-tobacco nicotine dependent patients were matched with 22,872 non-nicotine dependent patients. Non-tobacco nicotine dependent patients experienced higher associated risk for numerous postoperative complications compared to non-nicotine dependent patients including increased risk for mortality within 6 months postoperatively (RR 1.386, 10.7% vs 7.7%, P = 0.001), sepsis (RR 1.459, 4.4% vs 3.0%, P = 0.027), and pneumonia (RR 1.751, 5.8% vs 3.3%, P = 0.001).

Conclusions

Non-tobacco nicotine dependence increases postoperative complications for patients undergoing intramedullary nailing for intertrochanteric femur fractures. Our findings support the need for development of perioperative nicotine cessation guidelines for non-tobacco nicotine users.

Level of evidence

Level III, Prognostic.

Astragalus polysaccharide promotes osteogenic differentiation of human bone marrow derived mesenchymal stem cells by facilitating ANKFY1 expression through miR-760 inhibition

Aims

Astragalus polysaccharide (APS) participates in various processes, such as the enhancement of immunity and inhibition of tumours. APS can affect osteoporosis (OP) by regulating the osteogenic differentiation of human bone mesenchymal stem cells (hBMSCs). This study was designed to elucidate the mechanism of APS in hBMSC proliferation and osteoblast differentiation.

Methods

Reverse transcriptase polymerase chain reaction (RT-PCR) and Western blotting were performed to determine the expression of microRNA (miR)-760 and ankyrin repeat and FYVE domain containing 1 (ANKFY1) in OP tissues and hBMSCs. Cell viability was measured using the Cell Counting Kit-8 assay. The expression of cyclin D1 and osteogenic marker genes (osteocalcin (OCN), alkaline phosphatase (ALP), and runt-related transcription factor 2 (RUNX2)) was evaluated using quantitative reverse transcriptase polymerase chain reaction (qRT-PCR). Mineral deposits were detected through Alizarin Red S staining. In addition, Western blotting was performed to detect the ANKFY1 protein levels following the regulation of miR-760. The relationship between miR-760 and ANKFY1 was determined using a luciferase reporter assay.

Results

The expression of miR-760 was upregulated in OP tissues, whereas ANKFY1 expression was downregulated. APS stimulated the differentiation and proliferation of hBMSCs by: increasing their viability; upregulating the expression levels of cyclin D1, ALP, OCN, and RUNX2; and inducing osteoblast mineralization. Moreover, APS downregulated the expression of miR-760. Overexpression of miR-760 was found to inhibit the promotive effect of APS on hBMSC differentiation and proliferation, while knockdown of miR-760 had the opposite effect. ANKFY1 was found to be the direct target of miR-760. Additionally, ANKFY1 participated in the APS-mediated regulation of miR-760 function in hBMSCs.

Conclusion

APS promotes the osteogenic differentiation and proliferation of hBMSCs. Moreover, APS alleviates the effects of OP by downregulating miR-760 and upregulating ANKFY1 expression.

Influence of smoking on the healing of conservatively treated displaced midshaft clavicle fractures

Aims

Tobacco, in addition to being one of the greatest public health threats facing our world, is believed to have deleterious effects on bone metabolism and especially on bone healing. It has been described in the literature that patients who smoke are approximately twice as likely to develop a nonunion following a non-specific bone fracture. For clavicle fractures, this risk is unclear, as is the impact that such a complication might have on the initial management of these fractures.

Methods

A systematic review and meta-analysis were performed for conservatively treated displaced midshaft clavicle fractures. Embase, PubMed, and Cochrane Central Register of Controlled Trials (via Cochrane Library) were searched from inception to 12 May 2022, with supplementary searches in Open Grey, ClinicalTrials.gov, ProQuest Dissertations & Theses, and Google Scholar. The searches were performed without limits for publication date or languages.

Results

The meta-analysis included eight studies, 2,285 observations, and 304 events (nonunion). The random effects model predicted a pooled risk ratio (RR) of 3.68 (95% confidence interval 1.87 to 7.23), which can be considered significant (p = 0.003). It indicates that smoking more than triples the risk of nonunion when a fracture is treated conservatively.

Conclusion

Smoking confers a RR of 3.68 for developing a nonunion in patients with a displaced middle third clavicle fracture treated conservatively. We know that most patients with pseudarthrosis will have pain and a poor functional outcome. Therefore, patients should be informed of the significantly higher risks of nonunion and offered smoking cessation efforts and counselling. Moreover, surgery should be considered for any patient who smokes with this type of fracture.

LncRNA PCBP1-AS1 induces osteoporosis by sponging miR-126-5p/PAK2 axis

Aims

Long non-coding RNAs (lncRNAs) act as crucial regulators in osteoporosis (OP). Nonetheless, the effects and potential molecular mechanism of lncRNA PCBP1 Antisense RNA 1 (PCBP1-AS1) on OP remain largely unclear. The aim of this study was to explore the role of lncRNA PCBP1-AS1 in the pathogenesis of OP.

Methods

Using quantitative real-time polymerase chain reaction (qRT-PCR), osteogenesis-related genes (alkaline phosphatase (ALP), osteocalcin (OCN), osteopontin (OPN), and Runt-related transcription factor 2 (RUNX2)), PCBP1-AS1, microRNA (miR)-126-5p, group I Pak family member p21-activated kinase 2 (PAK2), and their relative expression levels were determined. Western blotting was used to examine the expression of PAK2 protein. Cell Counting Kit-8 (CCK-8) assay was used to measure cell proliferation. To examine the osteogenic differentiation, Alizarin red along with ALP staining was used. RNA immunoprecipitation assay and bioinformatics analysis, as well as a dual-luciferase reporter, were used to study the association between PCBP1-AS1, PAK2, and miR-126-5p.

Results

The expression of PCBP1-AS1 was pre-eminent in OP tissues and decreased throughout the development of human bone marrow-derived mesenchymal stem cells (hBMSCs) into osteoblasts. PCBP1-AS1 knockdown and overexpression respectively promoted and suppressed hBMSC proliferation and osteogenic differentiation capacity. Mechanistically, PCBP1-AS1 sponged miR-126-5p and consequently targeted PAK2. Inhibiting miR-126-5p significantly counteracted the beneficial effects of PCBP1-AS1 or PAK2 knockdown on hBMSCs' ability to differentiate into osteoblasts.

Conclusion

PCBP1-AS1 is responsible for the development of OP and promotes its progression by inducing PAK2 expression via competitively binding to miR-126-5p. PCBP1-AS1 may therefore be a new therapeutic target for OP patients.

Oligonucleotide Therapeutics for Age-Related Musculoskeletal Disorders: Successes and Challenges

Age-related disorders of the musculoskeletal system including sarcopenia, osteoporosis and arthritis represent some of the most common chronic conditions worldwide, for which there remains a great clinical need to develop safer and more efficacious pharmacological treatments. Collectively, these conditions involve multiple tissues, including skeletal muscle, bone, articular cartilage and the synovium within the joint lining. In this review, we discuss the potential for oligonucleotide therapies to combat the unmet clinical need in musculoskeletal disorders by evaluating the successes of oligonucleotides to modify candidate pathological gene targets and cellular processes in relevant tissues and cells of the musculoskeletal system. Further, we discuss the challenges that remain for the clinical development of oligonucleotides therapies for musculoskeletal disorders and evaluate some of the current approaches to overcome these.

Vaping Trends and Outcomes in Primary Total Joint Arthroplasty Patients: An Analysis of 21,341 Patients

INTRODUCTION

The effect of vaping on outcomes after total joint arthroplasty (TJA) and its prevalence in this patient population remain unclear. The purpose of this study was twofold: (1) to investigate the trends of vaping in TJA patients compared with patients who underwent routine physical examination and (2) to examine the influence vaping has on outcomes after TJA.

METHODS

Patients were classified as never vaped, former vape users, or whether they reported current vaping (CV). TJA patients were further classified based on whether they had no exposure to tobacco or vaping (NTNV), tobacco only (TO), both tobacco and vaping (BTV), or vaping only (VO).

RESULTS

The TJA group exhibited a steady trend of patients with CV status (P = 0.540) while patients in the routine physical examination cohort demonstrated a significant upward trend in CV status (P = 0.015). Subanalysis of TJA patients revealed that those in the VO category had significantly higher mean surgical time (P < 0.001), length of stay (P = 0.01), and rates of readmission (P = 0.001) compared with all other subgroups.

CONCLUSION

We found steady or increasing trends of electronic cigarette exposure in both groups over time. Additional efforts should be made to document electronic cigarette exposure for all patients.

A Mini Review on Osteoporosis: From Biology to Pharmacological Management of Bone Loss

Osteoporosis refers to excessive bone loss as reflected by the deterioration of bone mass and microarchitecture, which compromises bone strength. It is a complex multifactorial endocrine disease. Its pathogenesis relies on the presence of several endogenous and exogenous risk factors, which skew the physiological bone remodelling to a more catabolic process that results in net bone loss. This review aims to provide an overview of osteoporosis from its biology, epidemiology and clinical aspects (detection and pharmacological management). The review will serve as an updated reference for readers to understand the basics of osteoporosis and take action to prevent and manage this disease.

e-Cigarette Vapour Condensate Reduces Viability and Impairs Function of Human Osteoblasts, in Part, via a Nicotine Dependent Mechanism

Cigarette consumption negatively impacts bone quality and is a risk-factor for the development of multiple bone associated disorders, due to the highly vascularised structure of bone being exposed to systemic factors. However, the impact on bone to electronic cigarette (e-cigarette) use, which contains high doses of nicotine and other compounds including flavouring chemicals, metal particulates and carbonyls, is poorly understood. Here, we present the first evidence demonstrating the impact of e-cigarette vapour condensate (replicating changes in e-cigarette liquid chemical structure that occur upon device usage), on human primary osteoblast viability and function. 24 h exposure of osteoblasts to e-cigarette vapour condensate, generated from either second or third generation devices, significantly reduced osteoblast viability in a dose dependent manner, with condensate generated from the more powerful third generation device having greater toxicity. This effect was mediated in-part by nicotine, since exposure to nicotine-free condensate of an equal concentration had a less toxic effect. The detrimental effect of e-cigarette vapour condensate on osteoblast viability was rescued by co-treatment with the antioxidant N-Acetyl-L-cysteine (NAC), indicating toxicity may also be driven by reactive species generated upon device usage. Finally, non-toxic doses of either second or third generation condensate significantly blunted osteoblast osteoprotegerin secretion after 24 h, which was sustained for up to 7 days. In summary we demonstrate that e-cigarette vapour condensate, generated from commonly used second and third generation devices, can significantly reduce osteoblast viability and impair osteoblast function, at physiologically relevant doses. These data highlight the need for further investigation to inform users of the potential risks of e-cigarette use on bone health, including, accelerating bone associated disease progression, impacting skeletal development in younger users and to advise patients following orthopaedic surgery, dental surgery, or injury to maximise bone healing.

Alcohol-induced inhibition of bone formation and neovascularization contributes to the failure of fracture healing via the miR-19a-3p/FOXF2 axis

Aims

Alcoholism is a well-known detrimental factor in fracture healing. However, the underlying mechanism of alcohol-inhibited fracture healing remains poorly understood.

Methods

MicroRNA (miR) sequencing was performed on bone mesenchymal stem cells (BMSCs). The effects of alcohol and miR-19a-3p on vascularization and osteogenic differentiation were analyzed in vitro using BMSCs and human umbilical vein endothelial cells (HUVECs). An in vivo alcohol-fed mouse model of femur fracture healing was also established, and radiological and histomorphometric analyses were used to evaluate the role of miR-19a-3p. The binding of miR-19a-3p to forkhead box F2 (FOXF2) was analyzed using a luciferase reporter assay.

Results

miR-19a-3p was identified as one of the key regulators in the osteogenic differentiation of BMSCs, and was found to be downregulated in the alcohol-fed mouse model of fracture healing. In vitro, miR-19a-3p expression was downregulated after ethanol administration in both BMSCs and HUVECs. Vascularization and osteogenic differentiation were independently suppressed by ethanol and reversed by miR-19a-3p. In addition, the luciferase reporter assay showed that FOXF2 is the direct binding target of miR-19a-3p. In vivo, miR-19a-3p agomir stimulated callus transformation and improved the alcohol-impaired fracture healing.

Conclusion

This study is the first to demonstrate that the miR-19a-3p/FOXF2 axis has a pivotal role in alcohol-impaired fracture healing, and may be a potential therapeutic target.

Cite this article: Bone Joint Res 2022;11(6):386–397.

Auraptene ameliorates osteoporosis by inhibiting RANKL/NFATc1 pathway-mediated bone resorption based on network pharmacology and experimental evaluation

AIMS

The association of auraptene (AUR), a 7-geranyloxycoumarin, on osteoporosis and its potential pathway was predicted by network pharmacology and confirmed in experimental osteoporotic mice.

METHODS

The network of AUR was constructed and a potential pathway predicted by Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway and Gene Ontology (GO) terms enrichment. Female ovariectomized (OVX) Institute of Cancer Research mice were intraperitoneally injected with 0.01, 0.1, and 1 mM AUR for four weeks. The bone mineral density (BMD) level was measured by dual-energy X-ray absorptiometry. The bone microstructure was determined by histomorphological changes in the femora. In addition, biochemical analysis of the serum and assessment of the messenger RNA (mRNA) levels of osteoclastic markers were performed.

RESULTS

In total, 65.93% of the genes of the AUR network matched with osteoporosis-related genes. Osteoclast differentiation was predicted to be a potential pathway of AUR in osteoporosis. Based on the network pharmacology, the BMD and bone mineral content levels were significantly (p < 0.05) increased in the whole body, femur, tibia, and lumbar spine by AUR. AUR normalized the bone microstructure and the serum alkaline phosphatase (ALP), bone-specific alkaline phosphatase (bALP), osteocalcin, and calcium in comparison with the OVX group. In addition, AUR treatment reduced TRAP-positive osteoclasts and receptor activator of nuclear factor kappa-B ligand (RANKL)⁺nuclear factor of activated T cells 1 (NFATc1)⁺ expression in the femoral body. Moreover, the expressions of initiators for osteoclastic resorption and bone matrix degradation were significantly (p < 0.05) regulated by AUR in the lumbar spine of the osteoporotic mice.

CONCLUSION

AUR ameliorated bone loss by downregulating the RANKL/NFATc1 pathway, resulting in improvement of osteoporosis. In conclusion, AUR might be an ameliorative cure that alleviates bone loss in osteoporosis via inhibition of osteoclastic activity. Cite this article: Bone Joint Res 2022;11(5):304-316.

Fracture-related infection in osteoporotic bone causes more severe infection and further delays healing

Aims

With the ageing population, fragility fractures have become one of the most common conditions. The objective of this study was to investigate whether microbiological outcomes and fracture-healing in osteoporotic bone is worse than normal bone with fracture-related infection (FRI).

Methods

A total of 120 six-month-old Sprague-Dawley (SD) rats were randomized to six groups: Sham, sham + infection (Sham-Inf), sham with infection + antibiotics (Sham-Inf-A), ovariectomized (OVX), OVX + infection (OVX-Inf), and OVX + infection + antibiotics (OVX-Inf-A). Open femoral diaphysis fractures with Kirschner wire fixation were performed. Staphylococcus aureus at 4 × 10⁴ colony-forming units (CFU)/ml was inoculated. Rats were euthanized at four and eight weeks post-surgery. Radiography, micro-CT, haematoxylin-eosin, mechanical testing, immunohistochemistry (IHC), gram staining, agar plating, crystal violet staining, and scanning electron microscopy were performed.

Results

Agar plating analysis revealed a higher bacterial load in bone (p = 0.002), and gram staining showed higher cortical bone colonization (p = 0.039) in OVX-Inf compared to Sham-Inf. OVX-Inf showed significantly increased callus area (p = 0.013), but decreased high-density bone volume (p = 0.023) compared to Sham-Inf. IHC staining showed a significantly increased expression of TNF-α in OVX-Inf compared to OVX (p = 0.049). Significantly reduced bacterial load on bone (p = 0.001), enhanced ultimate load (p = 0.001), and energy to failure were observed in Sham-Inf-A compared to Sham-Inf (p = 0.028), but not in OVX-Inf-A compared to OVX-Inf.

Conclusion

In osteoporotic bone with FRI, infection was more severe with more bone lysis and higher bacterial load, and fracture-healing was further delayed. Systemic antibiotics significantly reduced bacterial load and enhanced callus quality and strength in normal bone with FRI, but not in osteoporotic bone.

Cite this article: Bone Joint Res 2022;11(2):49–60.

The Orthopedic Effects of Electronic Cigarettes: A Systematic Review and Pediatric Case Series

Electronic cigarette (EC) use is highly prevalent, especially in the adolescent population, where 29% of Canadian adolescents have used an EC in the past thirty days per national surveys. Our pediatric orthopedic referral centre observed a cluster of delayed unions of bone fractures in adolescents using ECs and present the case series here. We then asked whether electronic cigarettes impair bone healing or influence orthopedic outcomes. A PRISMA-compliant systematic review was carried out, which revealed no human clinical studies and a general paucity of evidence around ECs and musculoskeletal health. The existing experimental evidence relevant to orthopedics is summarized. The effect of ECs on the musculoskeletal system is poorly understood and is a target for further research.