Alcohol abuse and healing complications after cervical hip fractures

Impact of heavy alcohol consumption on cortical bone mechanical properties in male rhesus macaques

Chronic heavy alcohol consumption may influence the skeleton by suppressing intracortical bone remodeling which may impact the quality of bone and its mechanical properties. However, this aspect has not been thoroughly assessed in either humans or animal models whose cortical bone microstructure resembles the microstructure of human cortical bone. The current study is the first to investigate the effects of chronic heavy alcohol consumption on various mechanical properties of bone in a non-human primate model with intracortical remodeling. Male rhesus macaques (5.3 years old at the initiation of treatment) were induced to drink alcohol and then given the choice to voluntarily self-administer water or ethanol (4 % w/v) for approximately 14 months, followed by three abstinence phases (lasting 34, 41, and 39-46 days) with approximately 3 months of ethanol access in between. During the initial 14 months of open-access, monkeys in the alcohol group consumed an average of 2.9 ± 0.8 g/kg/d ethanol (mean ± SD) resulting in a blood ethanol concentration of 89 ± 47 mg/dl in longitudinal samples taken at 7 h after the daily sessions began. To understand the impact of alcohol consumption on material properties, various mechanical tests were conducted on the distal tibia diaphysis of 2-5 monkeys per test group, including dynamic mechanical analysis (DMA) testing, nano-indentation, microhardness testing, compression testing, and fracture resistance curve (R-curve) testing. Additionally, compositional analyses were performed using Fourier-transform infrared (FTIR) spectroscopy. Significant differences in microhardness, compressive stress-strain response, and composition were not observed with alcohol consumption, and only minor differences were detected in hardness and elastic modulus of the matrix and osteons from nanoindentation. Furthermore, the R-curves of both groups overlapped, with similar crack initiation toughness, despite a significant decrease in crack growth toughness (p = 0.032) with alcohol consumption. However, storage modulus (p = 0.029) and loss factor (p = 0.015) from DMA testing were significantly increased in the alcohol group compared to the control group, while loss modulus remained unchanged. These results indicate that heavy alcohol consumption may have only a minor influence on the material properties and the composition of cortical bone in young adult male rhesus macaques.

Osteonecrosis Related to Steroid and Alcohol Use-An Update on Pathogenesis

Osteonecrosis (ON) is usually a progressive disease that negatively affects the quality of life and leads to significant disability. Most patients are aged 30-50 years and require multiple surgical interventions throughout their lifetime. In non-traumatic ON, alcohol abuse and corticosteroids are involved in up to 80% of cases. This narrative review aims to summarize data on their impact on healthy bone and the development of pathophysiological processes leading to ON development. We conducted EMBASE and MEDLINE database reviews to identify relevant research. We found that for both agents, the risk was time and dose-dependent. ON in alcohol and steroid use shared many pathogenetic mechanisms leading to the development of necrosis, including increased adipogenesis, the induction of chronic inflammation, vascular alterations, and impaired bone-cell differentiation. Because both alcohol and steroid use are modifiable factors, both general physicians and orthopedic surgeons should encourage patients to limit ethanol intake and avoid corticosteroid overuse. In the presence of ON, because both alcohol- and steroid-induced disease tend to be multifocal, addiction treatment and limiting steroid use are justified.

Suboptimal outcomes after internal fixation for displaced intracapsular femoral neck fractures in 50- to 60-year-old patients

PURPOSE

The aim of this study was to evaluate outcomes of internal fixation for displaced femoral neck fracture (FNF) between 50 and 60 years old. The patient and surgical factors for the failure were identified.

METHODS

We retrospectively reviewed the records of 102 displaced FNF patients between 50 and 60 years old (mean age 54.9 years) who had undergone internal fixation between 2005 and 2016. The minimum follow-up was 12 months. Primary end points included loss of reduction, non-union, and osteonecrosis of the femoral head (ONFH). Preoperative Pauwel's angle, fixation timing and methods, reduction quality, removal of implant and medical comorbidities were analysed.

RESULTS

The overall failure rate was 44.1%. In multivariate logistic regression analysis, poor reduction quality (adjusted odds ratio [aOR] 4.38; 95% confidence interval [CI], 1.54-12.46) and internal fixation delayed more than 6 hours (aOR 3.24; 95% CI, 1.08-9.69) were risk factors for all causes of failure. In a stratified analysis, poor reduction quality (aOR 3.81; 95% CI, 1.11-13.04) and a history of alcohol dependency (aOR 4.91; 95% CI, 1.09-22.13) were risk factors for loss of reduction. Internal fixation delayed >6 hours (aOR 3.67; 95% CI, 1.05-12.77) and removal of implant (aOR 3.32; 95% CI, 1.02-10.77) were risk factors for ONFH.

CONCLUSIONS

The outcome of internal fixation of displaced FNF in patients between 50 and 60 years old is suboptimal. The patient selection is important. Non-alcohol dependency lowered early failure. Implant retention reduced ONFH. Surgery within 6 hours and good quality of reduction yield better results.

Alcoholism as a predictor for pseudarthrosis in primary spine fusion: An analysis of risk factors and 30-day outcomes for 52,402 patients from 2005 to 2013

Introduction

This study assessed the incidence and risk factors for pseudarthrosis among primary spine fusion patients.

Methods

Retrospective review of ACS-NSQIP (2005-2013). Differences in comorbidities between spine fusion patients with and without pseudarthrosis (Pseud, N-Pseud) were assessed using chi-squared tests and Independent Samples t-tests. Binary logistic regression assessed patient-related and procedure-related predictors for pseudarthrosis.

Results

52,402 patients (57yrs, 53%F, 0.4% w/pseudarthrosis). Alcohol consumption (OR:2.6[1.2-5.7]) and prior history of surgical revision (OR:1.6[1.4-1.8]) were risk factors for pseudarthrosis operation. Pseud patients at higher risk for deep incisional SSI (at 30-days:OR:6.6[2.0-21.8]). Pseud patients had more perioperative complications (avg:0.24 ± 0.43v0.18 ± 0.39,p=0.026).

Conclusions

Alcoholism and surgical revision are major risk factors for pseudarthrosis in patients undergoing spine fusion.

Complications after surgical treatment of femoral neck fractures in men with alcohol dependence syndrome: retrospective register analysis of 154 cases

PURPOSE

One-third of hip fractures occur in men. The causes underlying hip fractures in men differ from those in women and include alcohol abuse. This retrospective register study evaluated the trends and results associated with different surgical treatment methods for nondisplaced and displaced femoral neck fractures in male patients with alcohol dependence syndrome.

METHODS

Men with hip fractures were identified from a local district hospital database. Alcohol dependence syndrome was identified as a diagnosis in medical records.

RESULTS

For displaced fractures, implant survival after total hip arthroplasty was significantly lower compared to hemiarthroplasty. For nondisplaced fractures, implant survival of cannulated screws was significantly lower compared to sliding hip screws. Overall patient survival for males with alcohol dependence syndrome with hip fracture was 62% at 1 year and 49% at 2 years. Patient survival in this population did not differ between displaced and nondisplaced fractures or among different surgical methods.

CONCLUSION

Patients with alcoholism who had documented evidence of alcohol dependence syndrome represented nearly half of patients <70 years old with low-energy hip fracture. In patients with nondisplaced femoral neck fractures, stability of the internal fixation appeared to play a major role in implant survival; sliding hip screws should be considered over multiple cannulated screws. In patients with displaced fracture, total hip arthroplasty was associated with a significantly higher risk of complications leading to revision compared to hemiarthoplasty.

LEVEL OF EVIDENCE

Prognostic Level III.

Three-year outcomes of intracapsular femoral neck fractures fixed with sliding hip screws in adults aged under sixty-five years

INTRODUCTION

Intracapsular femoral neck fractures remain associated with high rates of post-traumatic femoral head necrosis, non-union, and revision surgery.

AIM

Our aim was to identify factors associated with revision surgery in intracapsular femoral neck fractures treated with sliding hip screws (SHS) in adults aged <65 years.

PATIENTS AND METHODS

Consecutive admissions were identified retrospectively from the Royal Victoria Hospital, Belfast, which was the largest volume hospital on the National Hip Fracture Database. Of 2201 hip fractures between 1st August 2008 and 31st December 2010, 97 (4%) intracapsular fractures treated with SHS in adults <65 years were followed for a mean of 2.9 years (range 0-6.6).

RESULTS

Twenty-one (22%) hips were revised to arthroplasty. Avascular necrosis developed in 28 (29%) femoral heads. Eight (8%) fractures proceeded to non-union. Displaced fractures (p<0.001, Fisher's exact [FE]), posterior comminution (p=0.049, FE), chronic respiratory disease (p=0.006, FE) and residual distraction (p=0.011, χ²) were associated with revision to arthroplasty. Multiple regression found displaced fractures (p=0.006) and chronic respiratory disease (p=0.017) significant; in the latter 4 of 6 were revised (67%), including all four patients with chronic obstructive pulmonary disease (COPD). Eleven (11%) individuals required walking aids before injury, which rose to 34 (35%) at one year (p<0.0001, χ²). Eighty-nine (92%) individuals could walk alone outdoors before injury, but only 76 (78%) at one year (p=0.009, χ²).

CONCLUSIONS

Displaced fractures in individuals with chronic respiratory disease should be considered high risk for revision to arthroplasty. Posterior cortex deficiency should be evaluated prior to choice of operation. Fracture biology and revascularisation play a greater role than operation timing. A significant proportion of individuals do not recovery pre-morbid mobility by one year.

Hip fractures and chronic alcohol excess: a series of 7,023 cases

We aim to compare trends in characteristics and outcomes for 131 patients with evidence of excess alcohol intake at the time of admission with a hip fracture against 6,892 hip fracture patients with no evidence of alcohol excess. Alcohol excess was determined by a finding of abnormal liver function tests in association with a history of excessive alcohol consumption. Patients who consumed excess alcohol were younger (64 versus 80 years mean age), more likely to be male (47% versus 22%), smoke cigarettes (54% versus 11%), be more mobile and less likely to use a walking aid (28% versus 46%). They were also more likely to sustain an extracapsular fracture (53% versus 39%) and to be living in their own homes at the time of injury (85% versus 66%). Hypertension and cardiac disease were less common in those with alcohol excess. Postoperatively those with alcohol abuse had a shorter hospital stay (mean nine days versus 16 days) but were at a greater risk of developing deep wound infections (2.3% versus 0.6%). For those patients who sustained intracapsular fractures treated by internal fixation there was an increased risk of fracture non-union occurring (29% versus 16%) but there were no other differences in operative complications.

Constructing the toolbox: Patient-specific genetic factors of altered fracture healing

The multifaceted sequence of events that follow fracture repair can be further complicated when considering risk factors for impaired union, present in a large and growing percentage of the population. Risk factors such as diabetes, substance abuse, and poor nutrition affect both the young and old alike, and have been shown to dramatically impair the body's natural healing processes. To this end, biotherapeudic interventions such as ultrasound, electrical simulation, growth factor treatment (BMP-2, BMP-7, PDGF-BB, FGF-2) have been evaluated in preclinical models and in some cases are used widely for patients with established non-union or risk/indication or impaired healing (ie. ultrasound, BMP-2, etc.). Despite the promise of these interventions, they have been shown to be reliant on patient compliance and can produce adverse side-effects such as heterotopic ossification. Gene and cell therapy approaches have attempted to apply controlled regimens of these factors and have produced promising results. However, there are safety and efficacy concerns that may limit the translation of these approaches. In addition, none of the above mentioned approaches consider genetic variation between individual patients. Several clinical and preclinical studies have demonstrated a genetic component to fracture repair and that SNPs and genetic background variation play major roles in the determination of healing outcomes. Despite this, there is a need for preclinical data to dissect the mechanism underlying the influence of specific gene loci on the processes of fracture healing, which will be paramount in the future of patient-centered interventions for fracture repair.

Intestinal healing in rats submitted to ethanol ingestion

PURPOSE

To study the effect of alcoholism on intestinal healing and postoperative complications in rats

METHODS

One hundred and sixty rats were divided into two groups: control and treated. The control group received water and the treated group 30% ethanol. After 180 days, colotomy with anastomosis were performed. After, the groups were divided into four subgroups: 20 rats for study at the following moments: 4(th), 7(th), 14(th) and 21(st) postoperative. The analyzed parameters were: weight gain, breaking strength, tissue hydroxyproline, postoperative complications and histopathological study

RESULTS

Weight gain was greater in the control group (p<0.05). When all the subgroups were clustered, breaking strength was significantly greater in the control (p<0.05). Histopathology and hydroxyproline dosage did not show differences. There were five surgical site infections in the treated group while the control group showed two (p>0.05). Nine fistulas occurred in the treated group whereas the control group two (p<0.05). There were three deaths in the control group and seven in the treated group (p>0.05).

CONCLUSIONS

Treated group undergo a malnutrition process that is revealed by lower weight gain. Impaired intestinal healing as indicated by smaller breaking strength. There were a larger number of postoperative complications in the treated animals.

Alcohol induced epigenetic perturbations during the inflammatory stage of fracture healing

It is well recognized by orthopedic surgeons that fractures of alcoholics are more difficult to heal successfully and have a higher incidence of non-union, but the mechanism of alcohol's effect on fracture healing is unknown. In order to give direction for the study of the effects of alcohol on fracture healing, we propose to identify gene expression and microRNA changes during the early stages of fracture healing that might be attributable to alcohol consumption. As the inflammatory stage appears to be the most critical for successful fracture healing, this paper focuses on the events at day three following fracture or the stage of inflammation. Sprague-Dawley rats were placed on an ethanol-containing or pair-fed Lieber and DeCarli diet for four weeks prior to surgical fracture. Following insertion of a medullary pin, a closed mid-diaphyseal fracture was induced using a Bonnarens and Einhorn fracture device. At three days' post-fracture, the region of the fracture calluses was harvested from the right hind-limb. RNA was extracted and microarray analysis was conducted against the entire rat genome. There were 35 genes that demonstrated significant increased expression due to alcohol consumption and 20 that decreased due to alcohol. In addition, the expression of 20 microRNAs was increased and six decreased. In summary, while it is recognized that mRNA levels may or may not represent protein levels successfully produced by the cell, these studies reveal changes in gene expression that support the hypothesis that alcohol consumption affects events involved with inflammation. MicroRNAs are known to modulate mRNA and these findings were consistent with much of what was seen with mRNA microarray analysis, especially the involvement of smad4 which was demonstrated by mRNA microarray, microRNA and polymerase chain reaction.

MicroRNAs: master regulators of ethanol abuse and toxicity?

Ethanol exerts complex effects on human physiology and health. Ethanol is not only addictive, but it is also a fetal teratogen, an adult neurotoxin, and an etiologic agent in hepatic and cardiovascular disease, inflammation, bone loss, and fracture susceptibility. A large number of genes and signaling mechanisms have been implicated in ethanol's deleterious effects leading to the suggestion that ethanol is a "dirty drug." An important question is, are there cellular "master-switches" that can explain these pleiotropic effects of ethanol? MicroRNAs (miRNAs) have been recently identified as master regulators of the cellular transcriptome and proteome. miRNAs play an increasingly appreciated and crucial role in shaping the differentiation and function of tissues and organs in both health and disease. This critical review discusses new evidence showing that ethanol-sensitive miRNAs are indeed regulatory master-switches. More specifically, miRNAs control the development of tolerance, a crucial component of ethanol addiction. Other drugs of abuse also target some ethanol-sensitive miRNAs suggesting that common biochemical mechanisms underlie addiction. This review also discusses evidence that miRNAs mediate several ethanol pathologies, including disruption of neural stem cell proliferation and differentiation in the exposed fetus, gut leakiness that contributes to endotoxemia and alcoholic liver disease, and possibly also hepatocellular carcinomas and other gastrointestinal cancers. Finally, this review provides a perspective on emerging investigations into potential roles of miRNAs as mediators of ethanol's effects on inflammation and fracture healing, as well as the potential for miRNAs as diagnostic biomarkers and as targets for therapeutic interventions for alcohol-related disorders.

Ethanol interferes with the measurement of extracellular ionized calcium

BACKGROUND

Maintenance of extracellular calcium (Ca) concentration within narrow limits is critical for normal cell function and optimization of bone health. Ionized Ca (iCa), the form of Ca that is regulated, has been reported to vary inversely with blood alcohol concentration (BAC). The mechanism by which ethanol decreases blood iCa levels is unknown. However, one possible explanation is that it is, at least partially, a methodological artifact due to an effect of ethanol on the function of the ion selective electrode used to measure iCa. The purpose of this study was to determine if ethanol interferes with the measurement of iCa and if this interference can account for the typically observed in vivo effects of ethanol consumption on blood iCa levels.

METHODS

Ethanol (0-5 microl/ml) was added to blood or iCa standards and the iCa concentration measured using the ICA2 iCa analyzer (Radiometer) or the I-Stat Clinical Analyzer (Abbott Laboratories). Both instruments use an ion selective electrode to measure iCa. The relationship between iCa and BAC determined from the ex vivo addition of ethanol to blood was compared with relationships obtained in vivo during chronic ethanol consumption.

RESULTS

Addition of ethanol to blood or iCa standards resulted in a dose-dependent decrease in iCa concentration when iCa was measured using the ICA2 analyzer but had no effect on iCa concentration when measured with the I-Stat Clinical Analyzer. Ethanol's effect on iCa with the ICA2 analyzer did not differ between blood and standards, and ethanol had no effect on pH, suggesting that the ethanol-induced decrease in iCa was due to a methodological artifact. However, the magnitude of ethanol's effect was small and does not account entirely for the relationship between iCa and BAC observed in vivo with chronic ethanol consumption.

CONCLUSION

Ethanol can interfere with the measurement of iCa using ion selective electrodes, but this interference depends on the analyzer used. This is a significant methodological issue that has largely been unrecognized in the field of alcohol research. Although this interference does not explain entirely the relationship between iCa and BAC observed in vivo in studies on chronic ethanol consumption, it complicates investigations designed to assess the effect of ethanol on Ca homeostasis.

Skeletal toxicity associated with chronic ethanol exposure in a rat model using total enteral nutrition

Chronic alcohol abuse decreases bone mass, inhibits osteoblast differentiation and function, increases fracture incidence, and delays fracture healing. Four studies were designed to use intragastric ethanol delivery as part of a total enteral nutrition (TEN) system to determine the negative systemic effects of chronic ethanol on 1) the rat skeleton and 2) local rapid bone formation during limb lengthening (distraction osteogenesis, DO). In study 1, three-point bending tests demonstrated that after 75 days of ethanol exposure, the tibiae had significantly lower load to failure versus control diet (p = 0.0006) or ad libitum chow-fed rats (p = 0.0029). Study 2 examined alcohol's effects on the density and cross-sectional area of the proximal tibial metaphysis using peripheral quantitative computed tomography and found that after 25 days of ethanol exposure the trabecular volumetric bone mineral density (p = 0.011) and cortical cross-sectional area (p = 0.011) were lower compared with controls. In study 3, a comparison of distracted tibial radiographs and histological sections demonstrated ethanol-related decreases in both gap mineralization (p = 0.03) and bone column formation (p = 0.01). Histological comparisons in study 4 reproduced the ethanol-related deficits in new bone formation during DO (p = 0.001). These results indicate that the TEN system is a viable model to study ethanol's effects on the skeleton and that chronic ethanol delivery via TEN decreases trabecular bone density, cortical area, and mature bone strength. Also, the DO studies demonstrate, for the first time, that chronic ethanol inhibits rapid bone formation during limb lengthening.

Skeletal response to alcohol

This review briefly assesses the well-established effects of alcohol consumption on bone and mineral metabolism and addresses areas of controversy that need additional research. Alcohol consumption is a risk factor for osteoporosis based on the frequent finding of a low bone mass, decreased bone formation rate, and increased fracture incidence in alcoholics. Alcohol also has been shown to reduce bone formation in healthy humans and animals and to decrease proliferation of cultured osteoblastic cells. On the other hand, it has been difficult to demonstrate alcohol-induced bone loss and increased fracture rate in population-based studies. Indeed, most population-based studies have shown a positive association between alcohol and bone mass and no change or a decrease in fracture risk. Overall, the evidence generally supports a detrimental effect of chronic alcohol abuse on the skeleton of men and a neutral or generally beneficial effect of light to moderate alcohol consumption, especially in older women. This latter putative beneficial effect may be due to a reduction in the age-related increase in bone remodeling associated with postmenopausal bone loss. Specific areas of research are recommended to clarify the dose and sex effects of alcohol consumption and to determine cellular and molecular mechanisms of action. The goals of this proposed research emphasis are to determine the degree of risk for the range of alcohol consumption, to set guidelines of consumption compatible with maintaining bone health, and to develop appropriate countermeasures to prevent or reverse the detrimental skeletal effects of alcohol abuse.