Pandemic of the century: COVID-19 in inflammatory rheumatic diseases of a national cohort with 3,532 patients.

Objectives: This study aimed to assess the clinical outcomes and risk factors for severe coronavirus disease 2019 (COVID-19) in patients with inflammatory rheumatic disease (IRD) of a national cohort. Patients and methods: The multicenter cross-sectional study was carried out between July 15, 2020, and February 28, 2021. Data collection was provided from a national network database system, and 3,532 IRD patients (2,359 males, 1,173 females; mean age: 48.7±13.9 years; range; 18 to 90 years) were analyzed. Demographics, clinics about rheumatic disease, comorbidities, smoking status, being infected with COVID-19, and the course of the infection were questioned by rheumatology specialists. Results: One hundred seventeen patients were infected with COVID-19, the hospitalization rate due to COVID-19 was 58.9%, and the mortality rate was 1.7%. There was no difference between the COVID-19 positive and negative groups in terms of rheumatic disease activities and receiving drugs. It was observed that patients with COVID-19 had worse compliance with isolation rules, and bacillus Calmette-Guérin (BCG) vaccination was less common. The mean age and the rate of smoking of hospitalized COVID-19 patients were higher than those without hospitalization. Conclusion: In this cohort, in which real-life data were analyzed, COVID-19 rates in IRD patients were similar to the general population for the same period. Compliance with the isolation rules and BCG vaccination attracted attention as components that reduce the risk of COVID-19 infection. The risk factors for hospitalization were older age and smoking.

High-dose intravenous anakinra treatment is safe and effective in severe and critical COVID-19 patients: a propensity score-matched study in a single center.

BACKGROUND: In COVID-19, severe disease course such as need of intensive care unit (ICU) as well as development of mortality is mainly due to cytokine storm. In this study, we aimed to evaluate the high-dose intravenous anakinra treatment response and outcome in patients with severe and critically ill COVID-19 compared to standard of care. METHODS: This retrospective observational study was carried out at a tertiary referral center. The study population consisted of two groups as follows: the patients receiving high-dose intravenous anakinra (anakinra group) between 01.09.2021 and 01.02.2022 and the patients treated with standard of care (SoC, control group) as historical control group who were hospitalized between 01.07.2021 and 01.09.2021. RESULTS: After the propensity score 1:1 matching, 79 patients in anakinra and 79 patients in SoC matched and were included into the analysis. Mean ± SD patient age was 67.4 ± 16.7 and 67.1 ± 16.3 years in anakinra and SoC groups, respectively (p = 0.9). Male gender was 38 (48.7%) in anakinra and 36 (46.2%) in SoC (p = 0.8). Overall, ICU admission was in 14.1% (n = 11) and 30.8% (n = 24) (p = 0.013; OR 6.2), intubation in 12.8% (n = 10) and 16.7% (n = 13) patients (p = 0.5), and 14.1% (n = 11) and 32.1% (n = 25) patients died in anakinra and control groups, respectively (p = 0.008; OR 7.1). CONCLUSION: In our study, mortality was lower in patients receiving anakinra compared to SoC. Intravenous high-dose anakinra is safe and effective treatment in patients with severe and critical COVID-19.

Quality of healthcare information on YouTube: psoriatic arthritis.

BACKGROUND: YouTube is an increasingly used platform for medical information. However, the validity of health-related information on psoriatic arthritis (PsA) on YouTube has not been determined. OBJECTIVE: The purpose of this study was to evaluate the accuracy and quality of YouTube videos concerning PsA. MATERIALS AND METHODS: A YouTube search was performed on April 18, 2021, using the keyword "psoriatic arthritis." Two independent raters accessed the content, source, and detailed characteristics of the included videos. The reliability and quality of the videos were analyzed using the modified DISCERN score, Journal of the American Medical Association benchmark criteria score, and global quality scale score. RESULTS: Of the 200 videos screened, 155 were included in the study after applying the exclusion criteria. A total of 132 (85.2%) videos revealed useful information about PsA, whereas the remaining 23 (14.8%) were misleading. Video interaction parameters including the median number of views, views per day, likes, dislikes, and comments demonstrated no significant difference between the two groups. The videos posted by universities and professional organizations displayed the highest reliability and quality scores. CONCLUSION: The majority of YouTube videos on PsA contained useful information. However, physicians should alert patients to the possibility of misinformation and non-validated sources. Professional organizations in the field of rheumatology, such as the American College of Rheumatology and European League Against Rheumatism, should consider collaborating with YouTube to deliver high-quality content.

Evaluation of hepatitis serology and frequency of viral reactivation in patients with inflammatory arthritis receiving biologic agents: a multicenter observational study.

To evaluate of hepatitis serology and reactivation frequency in patients with rheumatic disease receiving biologic agents. Our study included patients with inflammatory rheumatic diseases from 23 centers, who were followed up with biological therapy. Demographic and clinical characteristics of the patients, duration of drug use and hepatitis serology and the state of viral reactivation were analyzed. A total of 4060 patients, 2095 being males, were included in our study. Of the patients, 2463 had Ankylosing Spondylitis (AS), 1154 had Rheumatoid Arthritis (RA), 325 had Psoriatic Arthritis (PsA), and 118 had other inflammatory rheumatic diseases. When the viral serology of the patients was evaluated, 79 patients (2%) who were identified as HBs Ag positive, 486 (12%) patients who were HBs Ag negative and anti-HBc IgG positive and 20 patients (0.5%) who were anti-HCV positive. When evaluated on a disease-by-disease basis, the rate of HBsAg was found to be 2.5% in RA, 2% in AS and 0.9% in PsA. Viral reactivation was detected in 13 patients while receiving biologic agents. HBs Ag was positive in nine patients with reactivation and negative in four patients. Anti-HBc IgG, however, was positive. Six of these patients had AS, four had RA, and three had PsA. The development of hepatitis reactivation in 11.4% of HBs Ag positive patients and 0.82% of anti-HBc IgG positive patients due to the use of biologic agents is an important problem for this group of patients. Antiviral prophylaxis is recommended to be started especially in patients who are HBs Ag positive and who are using biologic agents due to viral reactivation. Therefore, it is important to carry out hepatitis screenings before biologic agent treatment and to carefully evaluate the vaccination and prophylaxis requirements.

The Evaluation of Personal Protective Equipment Usage Habit of Mining Employees Using Structural Equation Modeling.

Background: In occupational studies, it is a known situation that technical and organizational attempts are used to prevent occupational accidents. Especially in the mining sector, if these attempts cannot prevent occupational accidents, personal protective equipment (PPE) becomes a necessity. Thus, in this study, the main objective is to examine the effects of the variables on the use of PPE and identify important factors. Methods: A questionnaire was implemented and structural equation modeling was conducted to ascertain the significant factors affecting the PPE use of mining employees. The model includes the factors that ergonomics, the efficiency of PPE and employee training, and PPE usage habit. Results: The results indicate that ergonomics and employee training have no significant effect (p > 0.05) on the use of PPE. The efficiency of PPE has a statistically meaningful effect (p < 0.05) on the use of PPE. Various variables have been evaluated in previous studies. However, none of them examined the variables simultaneously. Conclusion: The developed model in the study enables to better focus on ergonomics and employee training in the PPE usage. The effectiveness of a PPE makes its use unavoidable. Emphasizing PPE effectiveness in OHS training and even showing them in practice will increase employees' PPE usage. The fact that a PPE with high effectiveness is also ergonomic means that it will be used at high rates by the employee.

Ultrasonographic evaluation of distal femoral and talar cartilage thicknesses in patients with early rheumatoid arthritis and their relationship with disease activity.

INTRODUCTION: The aims of this study were to compare the distal femoral and talar cartilage thicknesses by ultrasonography (US) between patients with early rheumatoid arthritis (RA) and healthy controls and to investigate the potential relationship of these parameters with disease activity and clinical parameters. METHODS: Fifty-five patients with RA with a disease duration of up to 12 months (RA group), and 55 healthy volunteers (control group) were included in the study. The bilateral distal femur and talus cartilage thicknesses of all participants were measured by US and compared between the groups. The relationship of the results with the clinical data of the patients with early RA was investigated. RESULTS: The distal femur (medial, central, and lateral) and talus cartilage thicknesses of both extremities were significantly lower in the RA group. The tender joint count was found to be slightly to moderately negatively correlated with cartilage thickness. However, no correlation was found between the swollen joint count and cartilage thickness. In addition, the disease activity scores were moderately and inversely correlated with cartilage thickness in certain areas. CONCLUSION: The results of this preliminary study using US indicate that the distal femoral and talus cartilage of patients with RA can be affected in the early period, and the cartilage thickness of patients seems to be associated with disease activity. These results may inspire new studies for the evaluation of femoral and talar cartilage with US. Key Points • The distal femoral and talus cartilage thicknesses seem to be affected in the early period of rheumatoid arthritis. • There may be a relationship between the distal femur and talus cartilage thicknesses and disease activity in patients with early rheumatoid arthritis. • The tender joint count appears to be more associated with cartilage thickness than the swollen joint count in patients with early rheumatoid arthritis.

Ultrasound-guided genicular nerve block versus physical therapy for chronic knee osteoarthritis: a prospective randomised study.

To compare the effectiveness of ultrasound-guided genicular nerve block (GNB) and physical therapy (PT) in patients with chronic knee osteoarthritis. A prospective randomised study with 102 patients (45-70 years) was performed wherein the patients received ultrasound-guided GNB (n = 51) and PT (n = 51) along with a standard home exercise programme. Scores for pain on a Visual Analogue Scale (VAS), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and 6-min walking test (6MWT) were assessed pre-treatment and at 2- and 12-weeks post-treatment. Both groups were comparable for sociodemographic characteristics. VAS scores (in mm) in the ultrasound-guided GNB group at 0, 2 and 12 weeks were 7.01 ± 1.36; 3.71 ± 2.18; 5.08 ± 2.22 (p < 0.001) and 6.64 ± 1.99; 4.35 ± 1.09; 5.25 ± 1.33, (p < 0.001) in the PT group. While the increase in the 6MWT test in the 2nd week was similar for both groups (p = 0.073), the increase in walking distance was greater in the ultrasound-guided GNB group at 12 weeks (p = 0.046). As compared to PT, ultrasound-guided GNB is beneficial in reducing pain and increasing functional and physical capacity, with greater retention of effects on the physical capacity seen at 12 weeks. Trial registration number: ClinicalTrials.gov (NCT04782401).

Quality of English-language videos available on YouTube as a source of information on osteoporosis.

Osteoporosis awareness is essential for preventing osteoporotic fractures. Social media platforms have enormous potential to both support and deter patients' decisions on healthcare. The current study demonstrated that the majority of YouTube videos on osteoporosis provide useful information with sufficient quality. PURPOSE: YouTube is the most popular video-sharing platform for patients seeking online information about their medical condition. However, there are concerns regarding the accuracy and quality of YouTube content. We aimed to analyze the quality of English-language YouTube videos on osteoporosis. METHODS: A YouTube search was performed on April 21, 2021, using the keywords "osteoporosis," "osteoporosis exercise," "osteoporosis diet," and "osteoporosis treatment." The reviewers recorded the content, source, and detailed characteristics of the included videos. The reliability and quality of the videos were analyzed using the modified DISCERN score and Global Quality Scale (GQS) score by a rheumatologist and endocrinologist. RESULTS: Of the 400 videos screened, 238 were included in the study after applying the exclusion criteria. A total of 205 (86.1%) videos revealed useful information about osteoporosis whereas 33 (13.9%) were misleading. In terms of quality, 48% of the videos were of high quality, 34% were of moderate quality, and 18% were of low quality. The videos posted by universities and professional organizations had the highest modified DISCERN and GQS scores indicating high reliability and quality. CONCLUSION: This study demonstrated that the majority of YouTube videos on osteoporosis contained useful information with sufficient quality. However, physicians should be aware of misleading information and correct any misinformation during face-to-face meetings with patients. YouTube should consider creating partnerships with professional organizations in the field of osteoporosis to produce high-quality videos in line with their new health content policy.

Educational quality of YouTube videos on musculoskeletal ultrasound.

INTRODUCTION/OBJECTIVES: A progressively growing number of rheumatologists have integrated musculoskeletal ultrasound (MSUS) as a prized tool in their daily clinical practice over the past two decades. Lately, YouTube is often used by healthcare professionals as an educational tool. This study aimed to analyze the quality of educational information available on YouTube pertaining to MSUS. METHOD: We performed a search using the keyword "musculoskeletal ultrasound" on YouTube in January 2021. Of the first 200 videos screened, 147 met the inclusion criteria. The quality and reliability of the videos were evaluated using the global quality score (GQS) and modified DISCERN score, and their popularity was assessed using the Video Power Index (VPI). RESULTS: Of the 147 videos evaluated, 58 (39.5%) were of high quality, 30 (20.4%) were of moderate quality, while 59 (40.1%) were of low quality. The modified DISCERN score and the duration of the videos were significantly higher in the high-quality videos than the moderate- and low-quality videos (p < 0.001 for all). The median number of views per day, likes, comments, and the popularity of the videos assessed with VPI were significantly higher in the high- and moderate-quality group compared to the low-quality videos (p < 0.001, p < 0.001, p = 0.007, and p < 0.001, respectively). CONCLUSION: The quality of YouTube videos as an educational source on MSUS is unsatisfactory. Professional organizations and physicians should consider creating more high-quality MSUS videos. YouTube should consider filtering out poor-quality videos in collaboration with experts in the field. Key Points • Although rheumatologists are increasingly using ultrasound as an extension of their exam, accessing musculoskeletal ultrasound training is still facing some challenges. • YouTube is commonly used as an educational source by medical students and healthcare professionals. • Approximately 60% of the videos related to musculoskeletal ultrasound on YouTube revealed high and moderate quality, while the remaining 40% were of low quality and not suitable for medical education. • A filtering mechanism is required to improve the quality of YouTube content on MSUS.

YouTube as a source of information on gout: a quality analysis.

YouTube is a popular video-sharing platform commonly visited by patients and healthcare professionals for medical information. Gout is the most frequent cause of inflammatory arthritis in adults. However, the accuracy and quality of gout-related information on YouTube are not fully known. Thus, the aim of this study was to assess the reliability and quality of YouTube videos pertaining to gout. A YouTube search was conducted using the keywords "gout", "gout arthritis", "gout treatment", and "gout diet". Of the 240 videos screened, 114 that met the inclusion criteria were included in the study. The number of days since upload, number of views, likes, dislikes, comments and duration of the videos were recorded. A Modified DISCERN tool and the Global Quality Scale (GQS) were used to evaluate the reliability and quality of the videos. Of the 114 analyzed videos, 87.72% were deemed as useful while 12.28% contained misleading information with higher viewership. The most common topic was "gout diet". The majority of the videos demonstrated high quality (57.89%), followed by intermediate quality (28.95%) while the percentage of low-quality videos was 13.16%. Videos posted by academic institutions/professional organizations and physicians had higher modified DISCERN and GQS scores indicating higher reliability and quality. This study demonstrated that the majority of YouTube videos on gout provide useful information. However, physicians should be aware of the limited nature of YouTube and correct any misinformation during face-to-face meetings. YouTube should consider avoiding misleading videos using validity scales such as modified DISCERN and GQS.

Using categorical data analyses in determination of dust-related occupational diseases in mining.

Dust-related occupational diseases are common in the mining sector. It is important to identify employees who have high potential for these diseases and to investigate the factors affecting disease formation. For this reason, dust and dust-related occupational diseases should be carefully investigated in mining operations. In this study, dust-related occupational diseases in an open-pit lignite mine were investigated. Firstly, dust measurements were performed and then a health check of all employees was implemented. The obtained data set was categorized by taking into account the occupation, age, experience and level of dust exposure of the employees. While the logistic regression analysis was performed to determine the probability of the diseases, a hierarchical loglinear model was established to investigate the factors in the occurrence of these diseases for those employees with the diseases. Therefore, the most important factors for the development of the diseases were determined by the hierarchical loglinear model.

YouTube for information about side effects of biologic therapy: A social media analysis.

OBJECTIVE: Biologic therapies are one of the most significant breakthroughs in the treatment of rheumatic diseases, although there is still some uncertainty surrounding long-term patient safety. Recently, a growing number of patients browse the Internet as a source of health-related information. We aimed to assess the quality of information available on YouTube videos regarding the side effects of biologic therapy. METHODS: We used the keywords "biologic therapy side effects," "biologic therapy risks," "biologic therapy safety," "biologic agents side effects," "biologic agents risks," and "biologic agents safety." Also, the generic and commercial names of biologic agents were searched on YouTube in May 2020. The quality and reliability of the videos was assessed according to the global quality score (GQS), DISCERN score. Video Power Index (VPI) used to assess both the view and the like ratios of the videos. RESULTS: Seventy-five videos were evaluated. According to the GQS, 31 videos (40.3%) were of high quality, 18 videos (23.4%) were of intermediate quality, and 28 videos (36.4%) were of low quality. The GQS was significantly positively correlated with the DISCERN score (P < .001). VPI scores were not correlated with DISCERN (P = .268) and GQS scores (P = .411). CONCLUSION: YouTube videos on the side effects of biologic therapy are informative for patients and physicians. High-quality videos are more reliable but may not be as popular as expected.

Application of Fuzzy Logic for Predicting of Mine Fire in Underground Coal Mine.

BACKGROUND: Spontaneous combustion of coal is one of the factors which causes direct or indirect gas and dust explosion, mine fire, the release of toxic gases, loss of reserve, and loss of miners' life. To avoid these incidents, the prediction of spontaneous combustion is essential. The safety of miner's in the mining field can be assured if the prediction of a coal fire is carried out at an early stage. METHOD: Adularya Underground Coal Mine which is fully mechanized with longwall mining method was selected as a case study area. The data collected for 2017, by sensors from ten gas monitoring stations were used for the simulation and prediction of a coal fire. In this study, the fuzzy logic model is used because of the uncertainties, nonlinearity, and imprecise variables in the data. For coal fire prediction, CO, O2, N2, and temperature were used as input variables whereas fire intensity was considered as the output variable.The simulation of the model is carried out using the Mamdani inference system and run by the Fuzzy Logic Toolbox in MATLAB. RESULTS: The results showed that the fuzzy logic system is more reliable in predicting fire intensity with respect to uncertainties and nonlinearities of the data. It also indicates that the 1409 and 610/2B gas station points have a greater chance of causing spontaneous combustion and therefore require a precautional measure. CONCLUSION: The fuzzy logic model shows higher probability in predicting fire intensity with the simultaneous application of many variables compared with Graham's index.

Symmetric polyarthritis as an initial symptom in granulomatosis with polyangiitis: A report of six cases and review of the literature.

Granulomatosis with polyangiitis (GPA) is a primary systemic vasculitis characterized by granulomatous inflammation. Arthritis in GPA is most commonly associated with large joints, particularly the knees and ankles; however, symmetrical polyarthritis of small joints has been rarely reported in literature. Here, we describe retrospective analysis of six patients with GPA showing initial symptom of symmetrical polyarthritis who were followed-up by three different rheumatology departments. Male sex, anti-cyclic citrulinated peptide negativity, and early arthritis period are important clues for GPA.

Three cases of anti-TNF induced myositis and literature review / Três casos de miosite induzida pelo anti-TNF e revisão da literatura

Abstract Anti-tumor necrosis factor drugs are frequently preferred in the treatment of rheumatologic diseases and other inflammatory diseases. The development of myositis after using anti-tumor necrosis factor drugs is a rare clinical condition. Here we aimed to report cases who developed myositis after using anti-tumor necrosis factor drugs and review the current literature. We report two cases of rheumatoid arthritis and a case of ankylosing spondylitis developed idiopathic inflammatory myopathy following anti-tumor necrosis factor therapy. In conclusion, myositis could develop during anti-tumor necrosis factor therapy, so these patients should be evaluated carefully initially for myositis and should be closely monitored due to the potential for developing myositis in treatment process.

Resumo Os fármacos antifator de necrose tumoral (anti-TNF) são frequentemente preferidos no tratamento de doenças reumatológicas e outras doenças inflamatórias. O desenvolvimento de miosite após o uso de anti-FNT é uma condição clínica rara. Este estudo objetivou descrever casos de pacientes que desenvolveram miosite após o uso de anti-TNF e fazer uma revisão da literatura atual. Descrevem-se dois casos de artrite reumatoide (AR) e um caso de espondilite anquilosante (EA) que desenvolveram miopatia inflamatória idiopática após o tratamento com anti-TNF. Em conclusão, pode haver desenvolvimento de miosite durante o tratamento com anti-TNF, de modo que esses pacientes devem ser cuidadosamente avaliados inicialmente à procura de miosite e devem ser cuidadosamente monitorados em razão do potencial de desenvolvimento de miosite no processo de tratamento

Effects of Local Low-Dose Alendronate Injections Into the Distraction Gap on New Bone Formation and Distraction Rate on Distraction Osteogenesis.

Bisphosphonates that constrain bone resorption have a direct effect on osteoclast function. In this experimental study, the effects of low-dose local alendronate injections on the distraction gap (DG) in rabbit mandible at 2 different rates were evaluated.The experimental study was conducted on 20 male, New Zealand white rabbits. The animals were divided into 3 experimental groups and 1 control group. Group 1 consisted of animals with distraction at the rate of 1 mm/day, receiving postoperative local low-dose alendronate local injections into the DG. Group 2 consisted of animals with distraction at the rate of 2 mm/day, receiving postoperative 0.75 µg/kg of alendronate local injections into the DG. Group 3 consisted of animals with distraction at the rate of 2 mm/day, receiving postoperative 0.2 mL local saline injections into the DG. Group 4 consisted of animals with distraction at the rate of 1 mm/day, receiving postoperative 0.2 mL local saline injections into the DG. All the injections were performed immediately postoperatively and for all groups at 1, 2, 3, and 4 weeks following surgery. The distraction zones were evaluated using dual-energy X-ray absorptiometry and histological analysis.Histologically, bone healing was found to be significantly accelerated in Groups 1 and 4 compared with Groups 2 and 3 (P < 0.05). Bone healing was superior in Group 1 and the difference was statistically significant compared with Group 4. There was a significant increase in mean bone mineral density in the 1 mm daily rate groups (Groups 1 and 4) compared with the 2 mm daily rate groups (Groups 2 and 3) (P < 0.05).Local low-dose alendronate injections could be an effective way for improving bone formation in distraction osteogenesis. Furthermore, the results of this study did not support the hypothesis that injections of local low-dose alendronate may allow 2 mm/day instead of 1 mm/day of elongation in the rabbit mandible.

Three cases of anti-TNF induced myositis and literature review.

Anti-tumor necrosis factor drugs are frequently preferred in the treatment of rheumatologic diseases and other inflammatory diseases. The development of myositis after using anti-tumor necrosis factor drugs is a rare clinical condition. Here we aimed to report cases who developed myositis after using anti-tumor necrosis factor drugs and review the current literature. We report two cases of rheumatoid arthritis and a case of ankylosing spondylitis developed idiopathic inflammatory myopathy following anti-tumor necrosis factor therapy. In conclusion, myositis could develop during anti-tumor necrosis factor therapy, so these patients should be evaluated carefully initially for myositis and should be closely monitored due to the potential for developing myositis in treatment process.

Stress Analysis of Zygomatic Implants on the Augmented Maxillary Sinus: Is It Necessary to Graft?

PURPOSE: Zygomatic implants are becoming an ideal therapy with advanced implant-supported prosthetic treatment for the posterior atrophic maxilla. The purpose of this study is to examine the quantity and distribution of stress, which was caused by zygomatic implants placed using intrasinus method with or without augmentation to the atrophic posterior maxilla. MATERIALS & METHODS: In this study, 3-dimensional atrophic edentulous maxilla models with and without sinus augmentation are designed with computer-aided programs. Stress analysis was carried out on the created computer models for maxillary alveolar cortical bone, for cortical bone in the zygomaticomaxillary suture, and for zygomatic spongy bone at the apex of the zygomatic implant and for metal substructure of Von Misses stress data. RESULTS: Having augmented the maxillary sinus with graft, it was observed that after the loading especially in the posterior region, the tensile and compressive stresses on the alveolar crest was distributed more homogeneously and the stress generated on the cortical bone was reduced through the graft. CONCLUSION: Although zygomatic implants are graftless solutions for athrophic maxilla, sinus augmentation will be useful for bearing stress around the implants.

Effect of Platelet-Rich Fibrin on Peripheral Nerve Regeneration.

PURPOSE: This study aimed to evaluate the effect of platelet-rich fibrin (PRF) on peripheral nerve regeneration on the sciatic nerve of rats by using functional, histopathologic, and electrophysiologic analyses. MATERIALS AND METHODS: Thirty female Wistar rats were divided randomly into 3 experimental groups. In group 1 (G1), which was the control group, the sciatic nerve was transected and sutured (n = 10). In group 2 (G2), the sciatic nerve was transected, sutured, and then covered with PRF as a membrane (n = 10). In group 3 (G3), the sciatic nerve was transected, sutured by leaving a 5-mm gap, and then covered by PRF as a nerve guide (n = 10). Functional, histopathologic, and electrophysiologic analyses were performed. RESULTS: The total histopathologic semiquantitative score was significantly higher in G1 compared to G2 and G3 (P < 0.05). Myelin thickness and capillaries were significantly lower in G3 compared to G1 (P < 0.05). There was no statistically significant difference between the groups with regard to the functional and electrophysiologic results. CONCLUSION: The study results suggest that PRF decreases functional recovery in sciatic nerve injury. Further studies are required to determine the efficacy of PRF on peripheral nerve regeneration.