Radiologic and histopathologic effects of favipiravir and hydroxychloroquine on fracture healing in rats.

Fracture healing is a process in which many factors interact. In addition to many treatments, physical and biological therapy methods that affect different steps of this process, there are many biological and chemical agents that cause fracture union delay. Although the number of studies on fracture healing is increasing day by day, the mechanism of fracture healing, which is not fully understood, still attracts the attention of all researchers. In this study, we aimed to investigate the effects of favipiravir and hydroxychloroquine used in the treatment of COVID-19. In this study, 48 male Wistar rats weighing 300 ± 50 g were used. Each group was divided into eight subgroups of six rats each to be sacrificed at the 2nd and 4th weeks and evaluated radiologically and histologically. Favipiravir (group 1), hydroxychloroquine (group 2), favipiravir + hydroxychloroquine (group 3), and random control (group 4) were used. A statistically significant difference was observed between the 15th day histological scoring averages of the groups (p < 0.05). Although there was no statistically significant difference between the 15th day radiological score distributions of the groups (p > 0.05), we obtained different results in terms of complete bone union distributions and radiological images of the fracture line. Although favipiravir has a negative effect on fracture union in the early period, favipiravir may have a positive effect on fracture union in the late period. We did not find any effect of hydroxychloroquine on fracture union.

Topical or intravenous administration of tranexamic acid accelerates wound healing.

OBJECTIVES: In this study, we aimed to investigate the morphological and histological effects of tranexamic acid (TA) on wound healing in a rat wound model. MATERIALS AND METHODS: A total of 24 adult male Wistar Albino rats were used in this study. All rats were simple randomly divided into three groups including eight rats in each group. A full-thickness skin defect was created on the back of the rats in all groups. Serum physiological (2 mL) was instilled saline drops after wound formation (control group). Wound was created and topical TA (0.12 to 0.15 mL [30 mg/kg]) was applied (local group). Intravenous TA (0.12 to 0.15 mL [30 mg/kg]) was applied intravenously before the wound was created (intravenous group). The wound diameters of the groups were photographed and measured on Days 0, 3, 7, 10, 14 and, at the end of Day 14, the rats were sacrificed and their histopathological results and wound diameters were compared. RESULTS: Fibroblast count values of the control group were found to be significantly lower than the local group (p=0.002), and no significant difference was observed between the local and intravenous groups (p>0.05). The collagen density (%) values of the control group were found to be significantly higher than the local and intravenous groups (p=0.016 and p=0.044). Wound diameter values of the control group on Day 10 day were found to be significantly higher than the local and intravenous groups (p=0.001). In addition, the wound diameter values of the control group on Day 14 were found to be significantly higher than the local and intravenous groups (p=0.001 and p=0.0001). The wound diameter changes of the control group on Days 0-10 were found to be significantly lower than the local and intravenous groups (p=0.001). In addition, the wound diameter changes of the control group on Days 0-14 were found to be lower than those of the local and intravenous groups (p=0.001 and p=0.0001). CONCLUSION: The use of local or intravenous TA may have positive effects on the fibroblast count and wound contraction in a rat wound model.

Rifaximine spacer application is not superior to local teicoplanin treatment in a rat model of osteomyelitis.

OBJECTIVE: Acute and chronic osteomyelitis generally require long-term antibiotic therapy and surgical debridement. Implant-associated osteomyelitis, particularly from methicillin-resistant Staphylococcus aureus (MRSA) strains, is difficult to treat. Rifaximin is an antibiotic derived from rifamycin which may be effective in the treatment of osteomyelitis in terms of its wide spectrum of action and pharmacological properties. The aim of this experimental study was to investigate the local efficacy of rifaximin in rat models with MRSA and implant associated osteomyelitis. METHODS: This study was carried out with 40 adult Wistar albino rats. The rats were randomly divided into 4 equal groups with 10 rats in each. An implant related MRSA osteomyelitis was created in the right tibia metaphysis of each rat by Norden's experimental osteomyelitis model. After 4 weeks, the implants of each tibia were removed and debridement was applied. Group 1 was designed as control group and no other treatment was applied other than debridement. Bone cement without any antibiotic was applied to Group 2, bone cement with teicoplanin was applied to Group 3 and bone cement with rifaximin was applied to Group 4. After 4 weeks from the second surgery, euthanasia was performed to the rats and the clinical, histopathological and microbiological results were compared. RESULTS: There was no statistically significant difference between the groups in clinical scoring. A statistically significant difference was found between the histopathological scores of Group 1 and Group 2 and the histopathological scores of Groups 3 and 4; the histopathological scores of Group 1 and Group 2 were found to be higher than Group 3 and Group 4. When the pre-and post-treatment colony numbers were compared, although there was a statistically significant difference between Group 3 and Group 2, no statistically significant difference was found between Group 4 and Group 1 results. CONCLUSION: In spite of its wide spectrum, the local efficacy of rifaximin in the treatment of osteomyelitis could not be demonstrated. This study shows the ability to shed light on some future comprehensive studies with the inclusion of infection markers.

Treatment of intertrochanteric femur fracture with closed external fixation in high-risk geriatric patients: can it be the most reliable method that reduces mortality to minimum compared to proximal femoral nail and hemiarthroplasty?

ABSTRACT: The optimal surgical treatment of intertrochanteric femur fractures (ITF) to minimize the increased mortality in geriatric patients with high anesthetic risk was investigated by comparing closed external fixation (EF), a minimal invasive and biological osteosynthesis technique, proximal femoral nail (PFN) and hemiarthroplasty (HA) methods.Three different surgical methods were performed to 167 patients who were admitted to our clinic for ITF between 2014 and 2020 and considered at high risk (American Society of Anesthesiologists III - American Society of Anesthesiologists IV) by the Anesthesiology and Reanimation Department. Patients with multi-trauma, osteoarthritis, those with malignancies and developmental hip dysplasia were excluded from the study. Group I included patients who underwent closed reduction - external fixation (n = 46), Group II included patients who underwent partial arthroplasty (n = 77), and Group III included those who received PFN (n = 44). All fractures were classified according to the Modified Evans (Kyle) method and divided into 2 categories as type 1-2 (stable) and type 3-4 (unstable).The mean operation duration was 23 minutes and follow-up time was 14 months in Group 1, in which there was no in-hospital mortality. Five patients died due to non-operative reasons within 1 year. The mean operation duration and follow-up time in Group 2 were 40 minutes and 12 months, respectively. Six patients (7.8%) died during the operation or hospitalization, while 17 patients died due to comorbidities within 1 year. In Group 3, the mean operation duration and follow-up time were 40 minutes and 13 months, respectively. One patient died during the operation and 1 patient (n = 2, 4.5%), within 24 hours in the postoperative intensive care unit. Seven patients died due to comorbidities within 1 year. Statistical analysis revealed that the mean duration of operation, postoperative hospital stay, overall mortality and blood product transfusion amount were significantly lower in the EF group compared to other treatment methods.Closed EF is the most reliable surgical method that can minimize mortality in geriatric patients compared to other surgical options, due to the short duration of the operation, no evacuation of the fracture hematoma, early mobilization, lack of blood transfusion requirement, and early union.