Designing and synthesis of injectable hydrogel based on carboxymethyl cellulose/carboxymethyl chitosan containing QK peptide for femoral head osteonecrosis healing.

Femoral head necrosis is a debilitating disorder that typically caused by impaired blood supply to the hip joint. In this study, a novel injectable hydrogel based on Oxidized Carboxymethyl Cellulose (OCMC)-Carboxymethyl Chitosan (CMCS) polymers containing an angiogenesis stimulator peptide (QK) with a non-toxic crosslinking interaction (Schiff based reaction) was synthesized to enhance angiogenesis following femoral head necrosis in an animal model. The physicochemical features of fabricated injectable hydrogel were analyzed by FTIR, swelling and degradation rate, rheometry, and peptide release. Also, the safety and efficacy were evaluated following an in vitro hydrogel injection study and an avascular necrosis (AVN) animal model. According to the results, the hydrogel exhibited an appropriate swelling ratio and water uptake (>90 %, 24 h) as well as a suitable degradation rate over 21 days accompanied by a continuous peptide release. Also, data showed that hydrogels containing QK peptide boosted the proliferation, differentiation, angiogenesis, and osteogenic potential of both Bone Marrow mesenchymal Stem Cells (BM-MSCs) and human umbilical vein endothelial cells (HUVECs) (****p < 0.0001 and ***p < 0.001, respectively). Furthermore, molecular and histological evaluations significantly demonstrated the overexpression of Runx2, Osteocalcin, Collagen I, VEGF and CD34 genes (**p < 0.01 and ***p < 0.001, respectively), and also femoral head necrosis was effectively prohibited, and more blood vessels were detected in defect area by OCMC-CMCS hydrogel containing QK peptide (bone trabeculae >9000, ***p < 0.001). In conclusion, the findings demonstrate that OCMC-CMCS-QK injectable hydrogel could be considered as an impressive therapeutic construct for femoral head AVN healing.

Spinopelvic Parameters as Risk Factors of Nonspecific Low Back Pain: A Case-Control Study.

Background: The effect of spinopelvic alignment on low back pain (LBP) incidence has been studied in many investigations. However, the interrelation between spinopelvic parameters and LBP is poorly understood. In particular, it is unknown whether particular patterns of spinopelvic parameters render nonspecific LBP. In this study, we aimed to evaluate the role of spinopelvic parameters as risk factors of nonspecific LBP. Methods: In this case-control study, spinopelvic parameters, including lumbar lordosis (LL), sacral slope (SS), pelvic tilt (PT), and pelvic incidence (PI), were compared between 148 patients with nonspecific LBP and 148 healthy controls. Demographic characteristics of the patients, such as age, gender, occupation, smoking, diabetes mellitus, and body mass index (BMI), were recorded as confounders. Spinopelvic parameters were assessed using radiographic findings in 2 groups. The analysis was done once as univariate (Kolmogorov-Smirnov test) and once as multivariate (multivariate logistic regression) analysis. Results: Univariate analysis showed that female gender, higher BMI, smoking, and blue-collar jobs were associated with a higher risk of nonspecific LBP. LL, SS, and PI, but not PT, were all greater in LPB patients in the univariate analysis regarding the spinopelvic parameters. Multivariate analysis showed female gender (odds ratio adjusted (ORAdj) = 4.26 [95% CI, 2.11-9.58]; P = 0.001) and LL (ORAdj = 1.58; [95% CI, 1.18-3.22]; P = 0.026) were predictable risk factors for Nonspecific LBP. Conclusion: Spinopelvic parameters, particularly LL, could be considered as risk factors of nonspecific LBP so that a more significant LL might indicate a greater risk of LBP. However, the role of other parameters in this association could not be neglected.

Coculture of adipose-derived mesenchymal stem cells/macrophages on decellularized placental sponge promotes differentiation into the osteogenic lineage.

BACKGROUND: Several factors like three-dimensional microstructure, growth factors, cytokines, cell-cell communication, and coculture with functional cells can affect the stem cells behavior and differentiation. The purpose of this study was to investigate the potential of decellularized placental sponge as adipose-derived mesenchymal stem cells (AD-MSCs) and macrophage coculture systems, and guiding the osteogenic differentiation of stem cells. METHODS: The decellularized placental sponge (DPS) was fabricated, and its mechanical characteristics were evaluated using degradation assay, swelling rate, and pore size determination. Its structure was also investigated using hematoxylin and eosin staining and scanning electron microscopy. Mouse peritoneal macrophages and AD-MSCs were isolated and characterized. The differentiation potential of AD-MSCs co-cultured with macrophages was evaluated by RT-qPCR of osteogenic genes on the surface of DPS. The in vivo biocompatibility of DPS was determined by subcutaneous implantation of scaffold and histological evaluations of the implanted site. RESULTS: The DPS had 67% porosity with an average pore size of 238 µm. The in vitro degradation assay showed around 25% weight loss during 30 days in PBS. The swelling rate was around 50% during 72 h. The coculture of AD-MSCs/macrophages on the DPS showed a significant upregulation of four differentiation osteogenic lineage genes in AD-MSCs on days 14 and 21 and a significantly higher mineralization rate than the groups without DPS. Subcutaneous implantation of DPS showed in vivo biocompatibility of scaffold during 28 days follow-up. CONCLUSIONS: Our findings suggest the decellularized placental sponge as an excellent bone substitute providing a naturally derived matrix substrate with biostructure close to the natural bone that guided differentiation of stem cells toward bone cells and a promising coculture substrate for crosstalk of macrophage and mesenchymal stem cells in vitro.

Evaluation of the short-term outcomes of anatomic ACL reconstruction with hamstring autograft in patients with generalized joint laxity: A retrospective case-control study.

PURPOSE: The outcomes of anterior cruciate ligament reconstruction (ACLR) in patients with generalized joint laxity (GJL) are not clearly understood. In this study, we compared the outcomes of ACLR with quadruple hamstring autograft between GJL and non-GJL patients. METHODS: In a retrospective case-control study, 36 patients with GJL, according to the Beighton and Horan Joint Mobility Index, who underwent ACLR surgery, were included. Forty-four group-matched non-GJL patients were included in the control group. The mean follow-up of the patients was 20.65 ± 6.93 months. The outcomes of ACLR were evaluated by the Lachman test, pivot shift test, anterior tibial translation and KT-1000 side-to-side difference, and International Knee Documentation Committee (IKDC) scale. RESULTS: The results of the Lachman and pivot shift test were not significantly different between the GJL and non-GJL patients (P = 0.67 and P = 0.27, respectively). The mean anterior tibial translation was 7.06 ± 1.41 mm in the GJL group and 6.11 ± 1.53 mm in the non-GJL group (P = 0.006). The mean KT-1000 side-to-side difference was 2.25 ± 1.31 mm in the case and 2.5 ± 1.44 mm in the control group (P = 0.42). The mean IKDC score of the patients was not significantly different between the GJL and non-GJL groups (66.1 ± 20.6 vs. 69.9 ± 16.1, P = 0.35). ACLR failure occurred in 2 (5.5%) patients of the GJL group and no patients of the control group (P = 0.21). CONCLUSION: The present findings suggest ACLR with quadruple hamstring autograft as an adequate treatment for GJL patients, at least in short-term follow-up.

Risk Communication in Early Containment of COVID-19 Pandemic in Iran: Implementation of the World Health Organization Strategic Preparedness and Response Plan (WHO-SPRP).

Background: Health systems must have functional and efficient preparedness and response plans to manage pandemics. Moreover, it is essential to adjust to changing circumstances and the dynamic character of pandemics. The World Health Organization (WHO) introduced the Strategic Preparedness and Response Plan (SPRP), emphasizing 144 measures across 10 pillars, helping governments prepare and respond to the coronavirus disease 2019 (COVID-19) pandemic. This study aimed to determine how the Iranian health system, based on the WHO-SPRP, addresses strategic preparedness and response plan in the COVID-19 pandemic at the national level. Methods: The WHO-SPRP was adopted and translated into Persian by 2 bilingual natives. The chief of the health office requested that authorized officers complete the SPRP. Then, a meeting was held by officers of related units involved in COVID-19 management to address the SPRP at regional and national levels. Results: Our findings suggest that up to August 2020, effective risk communication and community engagement were not fully established. Our response plan lacked evidence-based information and educational messaging to consistently shape public opinion and impression of a respiratory pandemic. Conclusion: The Iranian health care system and services were almost able to address the SPRP and perform the major indicators that the WHO had proposed. However, special attention should be paid to risk communication and community engagement to empower informed decision-making by individuals and communities.

The distance between new and previous incisions does not affect skin necrosis in total knee arthroplasty: a parallel-randomized controlled clinical trial.

BACKGROUND: To avoid skin necrosis, an 8 cm distance between the new and previous incision is recommended in patients undergoing total knee arthroplasty (TKA). It was hypothesized that making a new incision less than 8 cm of the prior scar does not increase the risk of skin complications, and the new incision can be made anywhere, regardless of the distance from the previous scar. This study investigated how making a new incision, irrespective of the previous scars, affects skin necrosis. METHODS: In this parallel, randomized clinical trial, by simple randomization method using a random number table, 50 patients with single longitudinal knee scars were randomly assigned to two groups with a 1:1 ratio and 25 participants in each group. Patients with a minimum age of 60 and a single longitudinal previous scar on the knee were included. The exclusion criteria were diabetes mellitus, hypertension, morbid obesity, smoking, vascular disorders, cardiopulmonary disorders, immune deficiencies, dementia, and taking steroids and angiogenesis inhibitors. TKA was performed through an anterior midline incision, regardless of the location of the previous scar in the intervention group. TKA was performed with a new incision at least 8 cm distant from the old incision in the control group. Skin necrosis and scar-related complications were evaluated on the first and second days and first, second, and fourth weeks after the surgery. Knee function was assessed using the Knee Society Score (KSS) six months after the surgery. RESULTS: The baseline characteristics of the groups did not differ significantly. The average distance from the previous scar was 4.1 ± 3.2 cm in the intervention group and 10.2 ± 2.1 cm in the control group. Only one patient in the control group developed skin necrosis (P-value = 0.31). Other wound-related complications were not observed in both groups. The mean KSS was 83.2 ± 10.2 and 82.9 ± 11.1 in the intervention and control groups, respectively (P-value = 0.33). CONCLUSIONS: It is possible that in TKA patients, the new incision near a previous scar does not increase the risk of skin necrosis and other complications.

A Study of Characteristic Features and Diagnostic Roles of X-ray and MRI in Calcifying Tendinitis of the Shoulder.

Background: Calcifying tendinitis (CT) is an enigmatic lesion with several obscure aspects and it is a common disorder of the upper extremity characterized by the presence of calcifications in rotator cuff tendons and synovial tissues. In this study, we aimed to review the demographic and clinical characteristics, as well as radiologic and treatment history in CT patients who were referred with shoulder pain. Methods: In this cross-sectional study, a total of 146 patients who were referred with a shoulder CT were included. The definitive diagnosis was based on a combination of plain radiograph and magnetic resonance imaging (MRI). A predesigned independent t test was used to capture demographic and clinical data, as well as radiologic and treatment histories, and a chi-square test was utilized to assess the statistical correlation between qualitative variables. Results: The median age of the patients was 42.5 years. The female to male ratio was 2.3 to 1. The complaint of restricted shoulder movement was recorded in 107 (73.3%) patients and more frequently in women (p = 0.042). Night pain was present in 109 (74.7%) patients. The current and previous diagnoses matched in 36.1% (13 out of 36) of patients who only had MRI and in 63.6% (35 out of 55) patients who had both MRI and plain radiograph with them. Supraspinatus tendon was the main site of calcified deposition 65% (95 out of 146). Conclusion: CT is frequent at the age of around 40 and in the female gender. The diagnosis should be based on a combination of radiography and MRI and not based on MRI alone. The efficacy of different conservative treatments remains to be unwrapped.

Calcaneostop Provides Favorable Short-term Outcomes in Patients With Flexible Flatfoot.

Background: Flatfoot is a relatively frequent deformity seen in almost 5% of children. It is classified into flexible and rigid flatfoot. Symptomatic flexible flatfoot (FFF) can be managed using several procedures, and calcaneostop is one of the procedures that has gained popularity recently. This study aimed to evaluate the outcome of the calcaneostop procedure using screws. Methods: We retrospectively evaluated 57 feet in 44 consecutive patients with FFF undergoing calcaneostop surgery. The same pediatric orthopedic surgeon performed all surgeries. Following a 10-mm incision on the sinus tarsi, a partial thread 6.5 cancellous screw size 40 was inserted. Achilles tendon lengthening was performed on all patients, and a short leg cast was applied. Pain relief, complications, and the change in the talocalcaneal (Kite), talometatarsal (Meary's), and calcaneal inclination (Pitch) angles were evaluated on plain radiographs using a paired t test. Results: Pain relief was achieved in 55 (96.5%) cases, and 2 (3.5%) patients experienced pain after surgery. Other complications, including nerve damage, infection, screw loosening, fracture, or position loss, were not observed. The mean preoperative and postoperative Meary's, Kite, and Pitch angles were 15.74 ± 2.02 (12.30-21.60), 8.72 ± 1.03 (7.20-10.60), 31.23 ± 1.97 (27.80-37.30), 21.30 ± 1.98 (18.50-24.60), 12.40 ± 1.64 (8.50-16.60), and 18.52 ± 1.97 (15.90-22.60), respectively. A significant improvement was observed in each angle following surgery (p<0.001). Conclusion: Calcaneostop is an inexpensive and simple procedure that avoids the involvement of several joints and uses a simple incision leaving a small scar. This procedure is remarkably successful and can be quite convenient.

Characteristic Features and Outcomes of Open Gunshot Fractures of Long-bones with Gustilo Grade 3: A Retrospective Study.

Background: The incidence of gunshot injuries is growing, and civilian orthopedics should be more aware of the treatment and consequences of these injuries. This study aimed to describe the characteristic features and complications of gunshot injuries to long-bones. Methods: A total of 50 patients who presented with an open gunshot fracture of the tibia, humerus, and femur in the emergency room of our hospital were included in this study. Primary irrigation and debridement, as well as prophylactic antibiotics, were administered in the emergency room. The treatment was performed either conservatively (n=4) or surgically (n=46). The external fixator, nailing, or plating was used for surgical fixation. Results: The mean age and follow-up duration of the patients were 32.3±9.9 years and 13.1±5.6 months, respectively. The most common injured long bone was the femur (32 of 50). Regarding the Gustilo grade, IIIa, IIIb, and IIIc were observed in 37, 7, and 5 patients, respectively. The Masquelet technique was used for 7 (14%) patients, and 12 (24%) cases had skin flaps. Furthermore, the vascular injury was present in 5 (10%) patients, and Malunion of the fracture site was observed in 5 (10%) cases. Nonunion of the fractured bone occurred in 13 (26%) patients that was significantly associated with the presence of vascular injuries (P=0.02). Postoperative infection occurred in 9 (18%) patients and was significantly associated with the presence of skin flap (P=0.014). Conclusion: Gunshot injuries of long bones are associated with a high incidence of post-treatment complications, such as infection and nonunion, and therefore, more intensive care should be taken to avoid these complications.

Evaluation of early complications, outcome, and mortality in Coronavirus Disease 2019 (COVID-19) infection in patients who underwent orthopedic surgery.

BACKGROUND: A higher mortality and morbidity rate has been reported in COVID-19 patients undergoing surgery. To reduce the morbidity and mortality rate in COVID-19 patients undergoing orthopedic procedures, we aimed to increase the threshold for surgical planning. METHODS: In a prospective cohort study, COVID-19 patients who underwent elective or emergent orthopedic surgery in three orthopedic surgery centers from February 2020 to September 2020 were included. In this period, 6751 patients were scheduled for orthopedic surgery. To increase surgical threshold planning, all patients with grade 5 of the American Society of Anesthesiologists (ASA) classification and patients with COVID-19 related moderate to severe pulmonary involvement were identified as high-risk patients and were excluded. RESULTS: 35 deaths occurred during the study. The frequency of deaths was significantly higher in patients with COVID-19, 6 (9.4%) than patients without COVID-19, 29 (0. 43%). The average hospitalization stay was 12.8 ± 12.1 days. The odds ratio (OR) for death was significantly higher in patients with COVID-19 than patients without COVID-19. [OR: 8.13, Confidence interval 95% (CI95%) (5.02-11.25), P: 0.001]. Four (6.3%) COVID-19-associated complications were recorded in this series that all were respiratory failure requiring unexpected postoperative ventilation. Twenty surgical complications (31.3%) were recorded. The odds ratio for ICU admission was significantly higher in patients with COVID-19 than patients without COVID-19. [OR: 5.46, CI 95% (2.68-8.68), P: 0.001]. CONCLUSIONS: An increased threshold for orthopedic surgery is suggested for COVID-19 patients with a mortality rate of 9.3%, which is less than the mortality rate in other studies. Level of evidence III.

Comparison of Students' Attitudes about the Effectiveness of Algorithm-based Education with Lecture-based Education.

Background: Training is a complex process, especially when the students are being prepared for patient's management. Therefore, the development of effective teaching methods is critical for to improvement of learning and communication between the content and concepts. In algorithm-based education, more focus is placed on more involvement of students in the subject, thereby providing a better understanding of the concept. In this study, we compared students' attitudes about the effectiveness of algorithm-based education (education based on the patient's complaints and symptoms) with lecture-based education in the learning ability of the medical students presented in the clinical course of the orthopedic group. Methods: This research is a single-group quasi-experimental study; we assessed the students' attitudes on a five-point Likert scale questionnaire with confirmed validity and reliability. The scores of two teaching methods were assessed after the training course, which was presented using the algorithmic method for selective titles and lectures for the other titles. Data were analyzed on SPSS software using a paired t-test. Results: A total of 220 internship medical students, including 58.7% of girls with a mean age of 22.9 ± 1.19 years, participated in the study. The mean score of the questions was 3.92±0.54 and 2.17±0.58 in the algorithmic and the lecture training, respectively. After comparing the results with a paired t-test, there was a significant difference between students' attitudes toward the two teaching methods (p ˂ 0.001), so the students' attitude was more positive toward the algorithm-based method. Conclusion: For the education of medical students, algorithm-based training is more efficacious compared to traditional methods such as lecture-based training.

Foot Metastasis: Review of 38 Cases.

Acrometastases are rare and account for approximately 0.1% of metastases. The most common primary cancer site is the lung, followed by colorectal and genitourinary system. We searched PubMed (www. pubmed.com), Google scholar (www.scholar.google.com), Science Direct (http://www.sciencedirect.com), and Springer (http://link.springer.com) databases, using a combination of controlled vocabulary and text word terms and reviewed the last 10 years literature in order to describe demographic trends, anatomical distribution, the most common primary sources of malignancy, and survival rates in the reports of foot metastases. In conclusion 38 cases were included in this review analysis. Lung and genitourinary system were the most frequent primary sites. Forefoot was involved in 71% of all metastases to foot either alone or in combination with other areas of the foot. Calcaneus was involved in about 23% of patients either alone or in combination with other foot bones.

The Impact of Depression, Personality, and Mental Health on Outcomes of Total Knee Arthroplasty.

BACKGROUND: Precise assessment of preoperative mental health and psychological determinants may be useful in identifying patients at risk for poor postoperative outcomes of total knee arthroplasty (TKA). The aim of this study was to investigate the influence of psychological status and physical and mental health on the outcome of patients undergoing TKA. METHODS: Fifty-two patients undergoing unilateral TKA were assessed preoperatively with Oxford Happiness Inventory, Eysenck Personality Inventory, 12-item short form health survey (SF-12), and Knee Injury and Osteoarthritis Outcome Score (KOOS) for evaluating depression, personality traits, physical and mental health, and function, respectively. At 1 year after surgery, health-related quality of life (HRQL) and function were assessed using the SF-12 and KOOS. RESULTS: HRQL and function of all personality traits increased significantly after TKA, without significant difference among them. Extroversion and neuroticism did not have significant correlation with subjective well-being, HRQL, and function before and after surgery. Subjective well-being and the baseline physical and mental health scores were correlated strongly and directly with postoperative physical component summary, mental component summary, and KOOS scores and their improvement. Among many factors that significantly affected the outcomes of TKA, the only independent predictor of physical, mental, and functional outcome was depression. CONCLUSIONS: Outcomes of surgery were not significantly different among diverse personality traits. Patients with less depressive symptoms and higher baseline mental and physical scores had significantly greater improvement in HRQL after surgery. The only independent factor affecting the physical, mental, and functional outcome was depression.

Rivaroxaban as an Alternative Agent for Heparin-Induced Thrombocytopenia.

Heparin-induced thrombocytopenia (HIT) is a high-risk adverse drug reaction because of its associated risk of life- and limb-threatening thrombosis. Rivaroxaban may be considered as an ideal nonheparin anticoagulant alternative for the management of HIT. In this preliminary retrospective study, the efficacy and safety of rivaroxaban to control the clinically suspected HIT (4Ts score 4 points or greater) were evaluated. Patients with chronic kidney disease, hepatic impairment, mechanical heart valves, and active bleeding were excluded. Forty-two eligible patients who received rivaroxaban for clinically suspected HIT were evaluated by medical records review, with 12-month follow-up after the first dose of rivaroxaban. End points included confirmed thrombosis (primary end point), mortality, and adverse treatment-related events. HIT-associated thrombosis was found in 17/42 (40.5%) patients before receiving rivaroxaban. After rivaroxaban therapy, platelet counts normalized in all patients, with only 1/42 (2.3%) patients developing new thrombosis. No hemorrhagic event was recorded in the patients. Twelve patients (28.6%) died, but the cause of death was not related to the thrombosis, hemorrhage, or adverse effects of rivaroxaban. Our findings are consistent with the available emerging data, suggesting that rivaroxaban is a safe and effective drug for the management of clinically suspected HIT. Rivaroxaban is a particularly valuable treatment option in developing countries, where there are issues of cost and availability of approved alternative agents.

MicroRNAs signatures, bioinformatics analysis of miRNAs, miRNA mimics and antagonists, and miRNA therapeutics in osteosarcoma.

MicroRNAs (miRNAs) involved in key signaling pathways and aggressive phenotypes of osteosarcoma (OS) was discussed, including PI3K/AKT/MTOR, MTOR AND RAF-1 signaling, tumor suppressor P53- linked miRNAs, NOTCH- related miRNAs, miRNA -15/16 cluster, apoptosis related miRNAs, invasion-metastasis-related miRNAs, and 14Q32-associated miRNAs cluster. Herrin, we discussed insights into the targeted therapies including miRNAs (i.e., tumor-suppressive miRNAs and oncomiRNAs). Using bioinformatics tools, the interaction network of all OS-associated miRNAs and their targets was also depicted.

Sagittal Spinopelvic Alignment in Asymptomatic Iranian Adults Aged 18 to 40 Years.

BACKGROUND: Recent studies have revealed the increasing importance of sagittal spinopelvic alignment. Knowing the values of sagittal spinopelvic parameters, which are affected by ethnicity, is essential in the normal asymptomatic population. In the current study, these parameters were measured in a sample of asymptomatic Iranian population. METHODS: Seventy asymptomatic participants without complaint of musculoskeletal problems were enrolled. They had no complaint about musculoskeletal problems. Lateral full-length spinal and pelvic x-rays were taken. The following parameters were measured on x-rays and presented as mean ± standard deviation: pelvic incidence (PI), sacral slope (SS), pelvic tilt (PT), lumbar lordosis (LL), thoracic kyphosis (TK), lumbar tilt (LT) and thoracic tilt (TT). RESULTS: The population consisted of 37 males and 33 females aged 26.6 ± 4.27 years. The mean values of PI, SS, PT, LL, TK, LT, and TT were 44.5 ± 10.1, 35.4 ± 6.7, 9.1 ± 7.9, 41.9 ± 14.7, 28.8 ± 8.3, 11.9 ± 7.4 and -7.5 ± 5.7 (median: -10; 5th percentile: -14; 95th percentile: 4.4) degrees, respectively. The variables were similar between males and females except for LL which was significantly higher in females (37.8 ± 16.5 versus 46.5 ± 11; P = 0.013). In addition, the linear regression model revealed age to be independently related with PI (beta = 0.344; P = 0.004) and PT (beta = 0.366; P = 0.002). PI (r = 0.344, P = 0.004) and PT (r = 0.359, P = 0.002) were positively correlated with age. Additionally, PI was positively correlated to SS, PT and LL and negatively to TT. CONCLUSION: These findings may be used as referential values for sagittal spinopelvic parameters in the Iranian population. The positive correlation of PI with age questions the constancy of PI throughout life. However, larger studies are required.

Significant effect of simvastatin and/or ezetimibe-loaded nanofibers on the healing of femoral defect: An experimental study.

BACKGROUND: Fracture healing complications are associated with significant healthcare and economic burden. In this study, we aimed to investigate how the combined administration of local simvastatin and ezetimibe into the femoral defect of the animal model affects the bone-healing process in comparison with their monotherapy. METHODS: A total of 32 four-month-old adult male Wistar rats were randomized into the four study groups: simvastatin + ezetimibe-loaded nanofibers (group 1), simvastatin-loaded nanofibers (group 2), ezetimibe-loaded nanofibers (group 3), and non-loaded nanofibers (group 4). After the generation of femoral defects, the predesigned nanofibers were locally administered into the defect site. The healing measures were serum and bone osteoprotegerin (OPG) expression, pathologic evaluation of union (Allen's fracture healing scores), and radiographic evaluation of bone density (Hounsfield scale) at weeks 2 and 4. RESULTS: The improvement of all evaluated healing measures was remarkably superior in rats that were treated with loaded nanofibers in comparison with the control group. Also, the improvement of all evaluated healing measures was considerably more in the simvastatin-ezetimibe combination therapy group compared to their monotherapy. All the evaluated measures were superior in the ezetimibe monotherapy group compared to the simvastatin monotherapy group. CONCLUSION: The cumulative effect of simvastatin and ezetimibe on the induction of bone healing is more significant than the individual effect of these drugs. Therefore, local administration of nanofibers loaded with simvastatin and ezetimibe could be regarded as a promising osteoinductive compound for the acceleration of bone repair.

Analysis of electrocautery smoke released from the tissues frequently cut in orthopedic surgeries.

BACKGROUND: Electrosurgical smoke could be different by the device of cutting or the type of tissue that is being cut. AIM: To analyze the electrocautery smoke released from the tissues that are frequently cut in orthopedic surgeries. METHODS: The released smoke from electrocautery of five different tissue types (meniscus, ligament, adipose, muscle, and synovium) of five patients who underwent total knee arthroplasty were collected and analyzed for volatile organic compounds (VOCs) and 27 candidate polycyclic aromatic hydrocarbons (n = 25). Surgical smoke was produced with an electrocautery device for 4 min. RESULTS: None of the 27 evaluated polycyclic aromatic hydrocarbons compounds were detectable in electrocautery smoke collected from the surgical cutting of the different tissues. The number and identity of detected VOCs were similar between the patients but not between tissue types. The number of detected VOCs was the highest in synovial tissue (n = 21) and the lowest in the meniscus and adipose tissue (n = 12). The number of toxic and/or carcinogenic VOCs were the most in the muscle and meniscus tissues (Toluene, Ethylbenzene, and Styrene). No toxic and/or carcinogenic VOCs were identified in the ligament and adipose tissue. CONCLUSION: Meniscus and muscle tissue are associated with the highest number of toxic and/or carcinogenic VOCs. Therefore, we recommend that surgeons avoiding the electrocautery of these tissues.

One-Bone Tarsus: A Case Report.

Tarsal coalition is a condition characterized by abnormal connections between ≥2 tarsi. Although tarsal coalition is not rare, tarsal coalitions involving >2 tarsi are very unusual. In this report, we describe a case of multiple tarsal coalitions in a 24-year-old male who experienced progressively worsening pain for 3 to 4 months before presenting for care. This case was unique in that all the tarsal and tarsometatarsal bones in the foot were fused and formed 1 integrated tarsal. All of the metatarsals were fused as well, and the patient had no joints or ranges of motion in the hindfoot or midfoot. The patient's pain was responsive to anti-inflammatory medications, and no surgical intervention was necessary. To the best of our knowledge, this is the most extensive case of multiple tarsal coalitions described in the literature to date.

Tenocyte-imprinted substrate: a topography-based inducer for tenogenic differentiation in adipose tissue-derived mesenchymal stem cells.

Tendon tissue engineering based on stem cell differentiation has attracted a great deal of attention in recent years. Previous studies have examined the effect of cell-imprinted polydimethylsiloxane (PDMS) substrate on induction differentiation in stem cells. In this study, we used tenocyte morphology as a positive mold to create a tenocyte-imprinted substrate on PDMS. The morphology and topography of this tenocyte replica on PDMS was evaluated with scanning electron microscopy (SEM) and atomic force microscopy. The tenogenic differentiation induction capacity of the tenocyte replica in adipose tissue-derived mesenchymal stem cells (ADSCs) was then investigated and compared with other groups, including tissue replica (which was produced similarly to the tenocyte replica and was evaluated by SEM), decellularized tendon, and bone morphogenic protein (BMP)-12, as other potential inducers. This comparison gives us an estimate of the ability of tenocyte-imprinted PDMS (called cell replica in the present study) to induce differentiation compared to other inducers. For this reason, ADSCs were divided into five groups, including control, cell replica, tissue replica, decellularized tendon and BMP-12. ADSCs were seeded on each group separately and investigated by the real-time reverse transcription polymerase chain reaction (RT-PCR) technique after seven and 14 days. Our results showed that in spite of the higher effect of the growth factor on tenogenic differentiation, the cell replica can also induce tenocyte marker expression (scleraxis and tenomodulin) in ADSCs. Moreover, the tenogenic differentiation induction capacity of the cell replica was greater than tissue replica. Immunocytochemistry analysis revealed that ADSCs seeding on the cell replica for 14 days led to scleraxis and tenomodulin expression at the protein level. In addition, immunohistochemistry indicated that contrary to the promising results in vitro, there was little difference between ADSCs cultured on tenocyte-imprinted PDMS and untreated ADSCs. The results of such studies could lead to the production of inexpensive cell culture plates or biomaterials that can induce differentiation in stem cells without growth factors or other supplements.