Malnutrition and Fracture Healing: Are Specific Deficiencies in Amino Acids Important in Nonunion Development?

Mass Spectrometry Reveals Molecular Effects of Citrulline Supplementation during Bone Fracture Healing in a Rat Model

Bone fracture healing is a complex process in which specific molecular knowledge is still lacking. The citrulline-arginine-nitric oxide metabolism is one of the involved pathways, and its enrichment via citrulline supplementation can enhance fracture healing. This study investigated the molecular effects of citrulline supplementation during the different fracture healing phases in a rat model. Microcomputed tomography (μCT) was applied for the analysis of the fracture callus formation. Matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI) and liquid-chromatography tandem mass spectrometry (LC-MS/MS) were used for lipid and protein analyses, respectively. μCT analysis showed no significant differences in the fracture callus volume and volume fraction between the citrulline supplementation and control group. The observed lipid profiles for the citrulline supplementation and control group were distinct for the different fracture healing stages. The main contributing lipid classes were phosphatidylcholines (PCs) and lysophosphatidylcholines (LPCs). The changing effect of citrulline supplementation throughout fracture healing was indicated by changes in the differentially expressed proteins between the groups. Pathway analysis showed an enhancement of fracture healing in the citrulline supplementation group in comparison to the control group via improved angiogenesis and earlier formation of the soft and hard callus. This study showed the molecular effects on lipids, proteins, and pathways associated with citrulline supplementation during bone fracture healing, even though no effect was visible with μCT.

Improved physical disability and nutritional status by bovine colostrum supplementation in adults with traumatic peri-trochanteric femoral fracture: A randomized, controlled, clinical trial

OBJECTIVES

Patients with femur fracture after surgery are at risk of malnutrition, weight loss, disability, and mobility complications. In the present study the role of colostrum supplementation on physical disability, and some nutritional variables after surgery has been investigated.

RESEARCH METHODS & PROCEDURES

Patients were randomly assigned to two groups. The intervention group received 45 g colostrum and the control group received 15 g whey protein daily for 21 days (each containing 12 g of protein). The trend comparison during 30 days of variables including weight, appetite, serum albumin level, hemoglobin and lymphocytes between the two groups was modeled with the generalized estimation equation. Moreover, the trend comparison during 90 days of Oswestry Disability Index (ODI) between the two groups was calculated.

RESULTS

The basic characteristics were the same between the two groups (colostrum, n = 46; control, n = 48). Protein intake was the same in both groups during the study period. There was a significant difference in weight gain (ß = 0.32, 95 % CI: 0.09-0.54; P = 0.005) within 30 days after operation between the colostrum and control groups in favor of the increase in the colostrum group. Compared to the control group, patients in the colostrum group had a 0.31 score more appetite (P < 0.001), 0.17 g/dL higher serum albumin level (P = 0.001), 0.5 mg/dL higher hemoglobin level and 440 more blood lymphocytes (P < 0.001) during the 30 days of intervention. Regarding physical function disability, patients in the colostrum group had about 4 ODI scores lower than the control group during the study period.

CONCLUSION

Colostrum supplement can increase appetite, hemoglobin, serum albumin level and the number of blood lymphocytes more than the control group. It can also accelerate weight gain and physical performance after surgery.

Strategies for Perioperative Optimization in Upper Extremity Fracture Care

Perioperative optimization in upper extremity fracture care must balance the need for timely treatment with the benefits of medical optimization. Care pathways directed at optimizing glycemic control, chronic anticoagulation, smoking history, nutrition, and frailty can reduce surgical risk in upper extremity fracture care. The development of multidisciplinary approaches that tie risk modification with risk stratification is needed.

Development and validation of a novel nomogram of 1-year mortality in the elderly with hip fracture: a study of the MIMIC-III database

OBJECTIVE

Hip fracture is a prevalent condition with a significant death rate among the elderly. We sought to develop a nomogram-based survival prediction model for older patients with hip fracture.

DESIGN

A retrospective case-control study.

SETTING

The data from Medical Information Mart for Intensive Care III (MIMIC-III V.1.4).

PARTICIPANTS

The clinical features of elderly patients with hip fracture, including basic information, comorbidities, severity score, laboratory tests and therapy, were filtered out based on the MIMIC-III V.1.4.

METHODS AND MAIN OUTCOME MEASURES

All patients included in the study were from critical care and randomly divided into training and validation sets (7:3). On the basis of retrieved data, the least absolute shrinkage and selection operator (LASSO) regression and multiple logistic regression analysis were used to identify independent predictive variables of 1-year mortality, and then constructed a risk prediction nomogram. The predictive values of the nomogram model were evaluated by the concordance indexes (C-indexes), receiver operating characteristic curve, decision curve analysis (DCA) and calibration curve.

RESULTS

A total of 341 elderly patients with hip fracture were included in this study; 121 cases died within 1 year. After LASSO regression and multiple logistic regression analysis, a novel nomogram contained the predictive variables of age, weight, the proportion of lymphocyte count, liver disease, malignant tumour and congestive heart failure. The constructed model proved satisfactory discrimination with C-indexes of 0.738 (95% CI 0.674 to 0.802) in the training set and 0.713 (95% CI 0.608 to 0.819) in the validation set. The calibration curve shows a good degree of fitting between the predicted and observed probabilities and the DCA confirms the model's clinical practicability.

CONCLUSIONS

The novel prediction model provides personalised predictions for 1-year mortality in elderly patients with hip fractures. Compared with other hip fracture models, our nomogram is particularly suitable for predicting long-term mortality in critical patients.

Investigation Of The Relationship Between Prognostic Nutrition Index And Mortality In Patients With Femur Fracture

Aim: The incidence of adverse postoperative outcomes in surgeries for femur fractures is high and is associated with malnutrition. In this study, it was aimed to determine the independent factors for 6-month survival in patients with femur fracture and to evaluate the predictive value of the prognostic nutrition index (PNI). Material and Method: One hundred and sixteen patients operated on only for femoral fracture were divided into survival and non-survival groups according to mortality.Demographic characteristics of the patients, operation data, fracture sites, need for intensive care unit and length of stay, postoperative hospital stay, and preoperative laboratory values, prognostic nutrition indices and mortality were evaluated. Results: Twenty-six (22.4%) of 116 patients who were operated for femoral fracture resulted in 6-month mortality. CRP, albumin, prealbumin, crp/albumin ratio and PNI values at admission were independent risk factors for postoperative mortality (p=0.014, p

Treatment of Femoral Shaft Pseudarthrosis, Case Series and Medico-Legal Implications

Pseudarthrosis (PSA) is a possible complication of femoral shaft fracture treatment. It is often associated with reduced bone quality and can, therefore, adversely affect quality of life. Its treatment poses a major challenge for orthopaedic surgeons. Several authors have set forth different surgical approaches for the treatment of pseudarthrosis, such as internal fixation with plate and screws, replacement of an intramedullary nail or prosthetic replacement. In cases associated with bone loss, osteopenia, or comminution of fracture fragments, autologous or homologous bone grafts may also be used. The chronic outcomes of the surgical treatment of femoral shaft pseudarthrosis, even when consolidation is achieved, are linked to disabling sequelae of clinical-functional relevance, deserving an adequate medico-legal evaluation. The purpose of this retrospective study is to analyse a clinical case series of patients treated for atrophic femoral shaft pseudarthrosis at the IRCCS Orthopaedic Institute Galeazzi, Milan, Italy, from 2014 to 2020 and their orthopaedic-traumatological and medico-legal implications.

Association of Body Mass Index with Long-Term All-Cause Mortality in Patients Who Had Undergone a Vertebroplasty for a Vertebral Compression Fracture

We aimed to investigate the association between preoperative body mass index (BMI) and postoperative long-term mortality in patients who underwent a vertebroplasty. We retrospectively enrolled patients with a vertebral compression fracture who underwent a vertebroplasty between May 2013 and June 2020 in a medical center in Taiwan. The survival status of the study sample was confirmed by the end of March 2021. Cox-proportional hazard models were conducted to examine the effects of being overweight/obese (≥25 kg/m2 vs. <25 kg/m2) and BMI (as a continuous variable) on all-cause mortality after adjusting for age, sex, history of smoking, diabetes, hypertension, chronic kidney disease, and osteoporosis. A total of 164 patients were analyzed (mean age 75.8 ± 9.3 years, male 25.6%, mean BMI 24.0 ± 4.1 kg/m2) after a median follow-up of 785 days. Compared with a BMI < 25 kg/m2, a BMI ≥ 25 kg/m2 was associated with a significantly lower risk of all-cause mortality (HR 0.297, 95% CI 0.101 to 0.878, p = 0.028). These findings were consistent when BMI was examined as a continuous variable (HR 0.874, 95% CI 0.773 to 0.988, p = 0.031). A low BMI (<22 kg/m2) should be considered as a risk factor for postoperative long-term mortality in this ageing population.

Oral L-arginine supplementation for fracture healing: a systematic review of preclinical studies

Introduction

Approximately 5 to 10% of all patients with fractures experience deficient fracture healing that results in fracture nonunions. Previous studies have shown that nitric oxide production from arginine could improve fracture healing by improving local blood supply, supplementing growth factors, and improving collagen synthesis. Apart from its simple oral mode of administration, this amino acid provides a non-toxic and inexpensive option for fracture healing. To date, no systematic reviews regarding oral L-arginine supplementation for fracture healing are available. We present the first systematic review of oral L-arginine supplementation for fracture healing.

Methods

A systematic literature search was carried out using PubMed, Google Scholar, and ScienceDirect until February 1, 2021 using a combination of text words. No date limits were set. Studies investigating the use of oral L-arginine supplementation for fracture healing were included. Reference lists of relevant publications were assessed for additional references. In addition, bibliographies from other reviews were searched.

Results

Four studies were included. Of these, 3 were animal studies, and the other one was an in vitro study. Animals that were given oral L-arginine supplementation had significantly increased angiogenesis, reduced defect area, higher osteoblasts and osteoclasts, and higher rate of bone formation compared to controls.

Conclusions

The available preclinical studies suggest that oral L-arginine supplementation is a potential new therapy for fracture healing. This amino acid supplement is not only affordable and non-toxic; it is also simple. Further clinical studies are required to investigate the optimal dose of oral L-arginine supplementation for fracture healing in human subjects.

Heat Stress Alters the Effect of Eimeria maxima Infection on Ileal Amino Acids Digestibility and Transporters Expression in Meat-Type Chickens

Simple Summary

Heat stress (HS) and Eimeria (E.) maxima infection are the most common physical and pathological stressors in chicken houses, and both affect intestinal digestibility and absorption leading to reduction in growth, morbidity, and mortality, causing massive economic losses. This study identifies the impact of each stressor and their combined effects on apparent amino acid digestibility and molecular transporters expression in the ileum of broiler chicken. Heat-stressed chickens showed no change in amino acids digestibility, despite the reduction in feed intake. Combining HS and E. maxima infection modulated the reduction in amino acids digestibility observed in the infected chickens. The expression of the ileal amino acid transporters was severely impacted by E. maxima infection but not by HS. Interestingly, the infected group reared under HS exhibited significantly higher expression levels in all the enterocytic apical and about half of the basolateral amino acid transporters than the infected birds raised in thermoneutral environment. Thus, HS putatively curtailed the maldigestion effects of E. maxima.

Abstract

Eimeria (E.) maxima invades the midgut of chickens and destroys the intestinal mucosa, impacting nutrient digestibility and absorption. Heat stress (HS) commonly affects the broiler chicken and contributes to inflammation and oxidative stress. We examined the independent and combined effects of HS and E. maxima infection on apparent amino acid ileal digestibility (AID) and mRNA expression of amino acid transporters in broiler chickens (Ross 708). There were four treatment groups: thermoneutral-control (TNc) and infected (TNi), heat-stress control (HSc) and infected (HSi), six replicates of 10 birds/treatment. Ileal content and tissue were sampled at 6 d post infection to determine AID and transporters expression. Surprisingly, the HSi chickens exposed to two critical stressors exhibited normal AID. Only the TNi group displayed reduction in AID. Using TNc as control, the HSc group showed upregulated CAT1, LAT4, TAT1, SNAT1, and SNAT7. The HSi group showed upregulated CAT1 and LAT1, and downregulated b^0,+AT, rBAT, SNAT1, and SNAT2. The TNi group showed upregulated CAT1, LAT1, and SNAT1 and downregulated B⁰AT1, b^0,+AT, rBAT, LAT4, and TAT1. The expression of all enterocytic-apical and about half of the basolateral transporters was higher in the HSi group than in the TNi group, indicating that HS can putatively alleviate the E. maxima adverse effect on ileal digestion and absorption.

Efficacy of adjuvant treatment for fracture nonunion/delayed union: a network meta-analysis of randomized controlled trials

Background

Fracture nonunion/delayed union seriously affects physical and mental health and quality of life. The aim of this study was to evaluate the relative efficacy of different adjuvant treatments for nonunion/delayed union by network meta-analysis.

Methods

A comprehensive search was performed to identify randomized controlled trials (RCTs) evaluating adjuvant treatment in the management of nonunion/delayed union. A network meta-analysis reporting on healing rate, healing time, and adverse effect (AE) outcomes was conducted to assess and compare different interventions.

Results

Thirty studies were included in the analysis. For the healing rate outcome, bone marrow aspirate (BMA) + autologous cancellous bone (ACB) was found to be significantly better than ACB alone (odds ratio: 0.12; 95% confidence interval: 0.03, 0.59). In the ranking results, BMA+ platelet-rich plasma (PRP) (96%), BMA + ACB (90%), and BMA alone (82%) showed relative advantages in the healing rate. Low-intensity pulsed ultrasonography (LIUS) intervention significantly shortened the healing time compared with ACB (SMD: -9.26; 95% CI: − 14.64, − 3.87). LIUS (100%), BMA + PRP (74%), and bone morphogenetic proteins (BMPs) (69%) have relative advantages. Compared with the control, electromagnetic field (EMF) (OR: 13.21; 95% CI: 1.58, 110.40) and extracorporeal shock wave (ESWT) (OR: 4.90; 95% CI: 1.38, 17.43) had a higher AE risk.

Conclusions

Among the current intervention strategies, BMA in combination with PRP and ACB can improve the healing rate of nonunion/delayed union. LIUS can significantly shorten the healing time. EMF and ESWT may have a high risk of AE. However, large-scale, well-designed studies are still needed to confirm the results.

Trial registration

Retrospectively registered.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12891-022-05407-5.

Inverse relation of body weight with short-term and long-term mortality following hip fracture surgery: a meta-analysis

Background

The obesity paradox, which suggests that high body weight is positively associated with survival in some diseases, has not been proven in patients with hip fracture. In this study, meta-analysis of previous studies on the impacts of body weight on postoperative mortality following hip fracture surgery in older adults was conducted.

Methods

PubMed, Embase, and Cochrane library were searched for studies investigating the correlation between mortality after hip fracture surgery and body weight. The search main items included: (“Body mass index” OR “BMI” or “body weight”) and (“hip fracture” or “hip fractures”). Studies contained data on short-term (≤ 30-day) and long-term (≥ 1 year) mortality after hip fracture and its association with distinct body weight or BMI groups were reported as full-text articles were included in this meta-analysis.

Results

Eleven separate studies were included. The definitions of underweight and obesity differed among the included studies, but the majority of the enrolled studies used the average body weight definition of a BMI of 18.5 to 24.9 kg/m²; underweight referred to a BMI of < 18.5 kg/m²; and obesity pertained to a BMI of > 30 kg/m². Based on the generalized definitions of body-weight groups from the enrolled studies, the group with obesity had lower long-term (odds ratio [OR]: 0.63, 95% CI: 0.50–0.79, P < 0.00001) and short-term (OR: 0.63, 95% CI: 0.58–0.68, P ≤ 0.00001) mortality rates after hip fracture surgery when compared with patients with average-weight group. However, compared with the average-weight group, the underweight group had higher long-term (OR: 1.51, 95% CI: 1.15-1.98, P=0.003) and short-term (OR: 1.49, 95% CI: 1.29-1.72, P<0.00001) mortality rates after hip fracture surgery.

Conclusions

Current evidence demonstrates an inverse relation of body weight with long-term and short-term mortality after hip fracture surgery in older adults.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13018-022-03131-3.

Exogenous PTH 1-34 Attenuates Impaired Fracture Healing in Endogenous PTH Deficiency Mice via Activating Indian Hedgehog Signaling Pathway and Accelerating Endochondral Ossification

Fracture healing is a complicated, long-term, and multistage repair process. Intermittent administration of parathyroid hormone (PTH) has been proven effective on intramembranous and endochondral bone formation during the fracture healing process, however, the mechanism is unclear. In this study, we investigated the role of exogenous PTH and endogenous PTH deficiency in bone fracture healing and explored the mechanism by using PTH knockout (PTH^-/-) mice and ATDC5 cells. In a mouse femur fracture model, endogenous PTH deficiency could delay endochondral ossification whereas exogenous PTH promotes accumulation of endochondral bone, accelerates cartilaginous callus conversion to bony callus, enhances maturity of bony callus, and attenuates impaired fracture healing resulting from endogenous PTH deficiency. In fracture callus tissue, endogenous PTH deficiency could inhibit chondrocyte proliferation and differentiation whereas exogenous PTH could activate the IHH signaling pathway to accelerate endochondral ossification and rescue impaired fracture healing resulting from endogenous PTH deficiency. In vitro, exogenous PTH promotes cell proliferation by activating IHH signaling pathway on ATDC5 cells. In mechanistic studies, by using ChIP and luciferase reporter assays, we showed that PTH could phosphorylate CREB, and subsequently bind to the promoter of IHH, causing the activation of IHH gene expression. Therefore, results from this study support the concept that exogenous PTH 1-34 attenuates impaired fracture healing in endogenous PTH deficiency mice via activating the IHH pathway and accelerating endochondral ossification. Hence, the investigation of the mechanism underlying the effects of PTH treatment on fracture repair might guide the exploration of effective therapeutic targets for fracture.

Effect of dietary amino acids L-arginine and lysine on implant osseointegration

Background:

Low protein diets have been linked to decreased bone strength in humans. Arginine and lysine can help improve the healing process and stimulate growth factors.

Aim:

To evaluate if dietary arginine and lysine combination aids in reducing the time frame for osseo-integration process and bone formation in animal models.

Materials and Methods:

Controls (Group I) and Experimental (Group II) consisted of twelve New Zealand rabbits. Animals in the experimental group were fed a conventional pellet food, water, and the amino acids L-Lysine and L-Arginine (Biovea, USA), whereas those in the control group were offered a standard diet. In both groups of animals, titanium implants measuring 2.5mm* 6mm were implanted in each tibial osteotomy. At the end of two weeks, four weeks, and eight weeks, the animals were euthanized. The tibial bone was removed and preserved in 1% formalin. The samples were analysed histologically for presence or absence of Necrosis, presence or absence of clot formation, Vascularization, Fibroblast, Osteoblasts and Osteoid Bone growth.

Results:

Histological outcomes on vascularization, fibroblasts, osteoblasts, osteoid bone growth inferred no significant variation between the control and experimental groups after 8 weeks (P>.05).

Conclusion:

Vascularity, clot organisation, osteoblasts, fibroblasts, and osteoid bone production in the protein fed experimental group animals were better in initial stages of healing when compared to control groups.

The need for nutritional assessment and interventions based on the prognostic nutritional index for patients with femoral fractures: a retrospective study

Background

The incidence of adverse perioperative outcomes in surgery for femoral fractures is high and associated with malnutrition. Here, we identified independent factors and assessed the predictive value of the prognostic nutritional index (PNI) for perioperative adverse outcomes in patients with femoral fractures.

Methods

This retrospective study included 343 patients who underwent surgery for a single femur fracture. Demographic characteristics, surgery and anaesthesia records and blood test results at admission, 1 day postoperatively and before discharge were evaluated using logistic regression analysis. The discriminatory ability of the independent factors was assessed using the receiver operating characteristic curve analysis, and DeLong’s test was used to compare the area under the curve (AUC).

Results

Overall, 159 patients (46.4%) experienced adverse perioperative outcomes. Amongst these, 123 (35.9%) had lower limb vein thrombus, 68 (19.8%) had hospital-acquired pneumonia, 6 (1.7%) were transferred to the postoperative intensive care unit, 4 (1.2%) had pulmonary embolism, 3 (0.9%) died during hospitalisation and 9 (2.6%) had other adverse outcomes, including incision disunion, renal and liver function impairment, acute heart failure, acute cerebral infarction and stress gastroenteritis. The PNI at admission, age, postoperative hospital stay, time to admission, hypertension, combined injures and surgery type were independent factors for adverse perioperative outcomes. Based on the AUC (PNI at admission: 0.772 [0.723–0.821], P < 0.001; age: 0.678 [0.622–0.734], P < 0.001; postoperative hospital stay: 0.608 [0.548–0.668], P = 0.001; time to admission: 0.585 [0.525–0.646], P = 0.006), the PNI at admission had optimal discrimination ability, indicating its superiority over other independent factors (age vs. PNI at admission, P = 0.002; postoperative hospital stay vs. PNI at admission, P < 0.001; time to admission vs. PNI at admission, P < 0.001).

Conclusions

Patients with femoral fractures require a nutritional assessment and appropriate nutritional intervention at admission, and that the PNI value at admission may be a good nutritional assessment indicator.

Bone Healing and Inflammation: Principles of Fracture and Repair

Bones comprise a significant percentage of human weight and have important physiologic and structural roles. Bone remodeling occurs when healthy bone is renewed to maintain bone strength and maintain calcium and phosphate homeostasis. It proceeds through four phases: (1) cell activation, (2) resorption, (3) reversal, and (4) bone formation. Bone healing, on the other hand, involves rebuilding bone following a fracture. There are two main types of bone healing, primary and secondary. Inflammation plays an integral role in both bone remodeling and healing. Therefore, a tightly regulated inflammatory response helps achieve these two processes, and levels of inflammation can have detrimental effects on bone healing. Other factors that significantly affect bone healing are inadequate blood supply, biomechanical instability, immunosuppression, and smoking. By understanding the different mechanisms of bone healing and the factors that affect them, we may have a better understanding of the underlying principles of bony fixation and thereby improve patient care.

A probable atypical ulnar fracture in a man receiving denosumab

BACKGROUND

Atypical femur fractures are widely recognized and associated with anti-resorptive therapy, most commonly bisphosphonates. These fractures generally occur in the femoral shaft or subtrochanteric region. Cases of atypical fractures at non-femur sites, including the ulna, have been reported.

CASE REPORT

Here we report a probable atypical ulnar fracture in a man receiving denosumab, who had been using his upper extremities for transfers and ambulation. Radiographs demonstrated a non-comminuted, transverse fracture somewhat similar to findings of atypical femur fractures. He was deemed a poor surgical candidate and treated with teriparatide. To our knowledge, this is the first reported probable atypical ulnar fracture potentially associated with denosumab use.

CONCLUSION

We believe it important that clinicians be aware of the association of anti-resorptive therapy with atypical fractures not only of the femur, but also at other skeletal sites. In patients on long-term anti-resorptive therapy, it is appropriate to consider that persistent "prodromal" pain might indicate an impending atypical fracture at an atypical skeletal site.

The biology and treatment of acute long-bones diaphyseal fractures: Overview of the current options for bone healing enhancement

Diaphyseal fractures represent a complex biological entity that could often end into impaired bone-healing, with delayed union and non-union occurring up to 10% of cases. The role of the modern orthopaedic surgeon is to optimize the fracture healing environment, recognize and eliminate possible interfering factors, and choose the best suited surgical fixation technique. The impaired reparative process after surgical intervention can be modulated with different surgical techniques, such as dynamization or exchange nailing after failed intramedullary nailing. Moreover, the mechanical stability of a nail can be improved through augmentation plating, bone grafting or external fixation techniques with satisfactory results. According to the "diamond concept", local therapies, such as osteoconductive scaffolds, bone growth factors, and osteogenic cells can be successfully applied in "polytherapy" for the enhancement of delayed union and non-union of long bones diaphyseal fractures. Moreover, systemic anti-osteoporosis anabolic drugs, such as teriparatide, have been proposed as off-label treatment for bone healing enhancement both in fresh complex shaft fractures and impaired unions, especially for fragility fractures. The article aims to review the biological and mechanical principles of failed reparative osteogenesis of diaphyseal fractures after surgical treatment. Moreover, the evidence about the modern non-surgical and pharmacological options for bone healing enhancement will discussed.

The Role of Diet in Osteoporotic Fracture Healing: a Systematic Review

PURPOSE OF REVIEW

Summarize the in vivo evidences on the association between nutrition and osteoporosis fracture healing.

RECENT FINDINGS

Osteoporotic fractures constitute a considerable public health burden. The healing capacity of fractures is influenced by local factors related to the fracture and by general factors (e.g., age, sex, osteoporosis, muscular mass, smoking, alcohol, drugs, and diet). The systematic review was conducted according to PRISMA statement. From the literature search on PubMed and Web of Science, from January 2016 to October 2019, twelve studies were selected and resulted highly variable in samples, exposure, methods, outcomes, and outcome assessment. Eleven studies were conducted on laboratory animals. Only one study aimed to investigate the impact of nutritional status on fracture healing in osteoporotic patients. In this review, the role of calcium/vitamin D supplementation remained controversial, while sialoglycoprotein supplementation, phytoestrogen-rich herb extract, flavonoids, and phosphorylated peptides showed a positive effect on osteoporotic fracture healing.

Progress in Photobiomodulation for Bone Fractures: A Narrative Review

Objective: The aim of this article is to examine current concepts and the future direction of implementing photobiomodulation (PBM) for fracture treatment. Background data: The effectiveness of PBM for bone regeneration has been demonstrated throughout in vitro studies and animal models. Yet, insufficient clinical trials have been reported on treating fractures with PBM. Materials and methods: A narrative review was composed on the basis of a literary search. Inclusion criteria consisted of studies between 2000 and 2019 using animal or human fracture models. Exclusion criteria consisted of studies that did not pertain to complete fractures or used other forms of intervention. Results: Ten animal studies on rats and rabbits and four clinical trials were found on using PBM for complete fractures. Conclusions: Based on positive outcomes in animal trials, parameter optimization of PBM for human fractures still requires extensive research on factors such as dosage, wavelength, penetration depth, treatment frequency, and the use of pulsed waves.

Allogenic Bone Graft Enriched by Periosteal Stem Cell and Growth Factors for Osteogenesis in Critical Size Bone Defect in Rabbit Model: Histopathological and Radiological Evaluation

Background & Objective:

This study aimed to investigate the effect of decellularized allogeneic bone graft enriched by periosteal stem cells (PSCs) and growth factors on the bone repair process in a rabbit model, which could be used in many orthopedic procedures.

Methods:

In this experimental study, a critical size defect (CSD) (10 mm) was created in the radial diaphysis of 40 rabbits. In group A, the defect was left intact with no medical intervention. In group B, the defect was filled by a decellularized bone graft. In group C, the defect was implanted by a decellularized bone graft enriched with platelet growth factors. In group D, the defect was treated by a decellularized bone graft seeded by periosteal mesenchymal stem cells (MSCs). Also, in group E, the defect was filled by a decellularized bone graft enriched with platelet growth factors and periosteal MSCs. Radiological evaluation was done on the first day and then in the second, fourth, and eighth weeks after the operation. The specimens were harvested on the 28th and 56th postoperative days and evaluated for histopathological criteria.

Results:

The radiologic and microscopic analysis of the healing process in bone defects of the treated groups (C, D, and E) revealed more advanced repair criteria than those of groups A and B significantly (P<0.05).

Conclusion:

Based on this study, it appears that implantation of concentrated PSCs in combination with growth factors and allogeneic cortical bone graft is an effective therapy for the repair of large bone defects.