Objective: This study aimed to examine systemic erythropoietin’s effect on the Achilles tendon’s healing in a rat model. Methods: Twenty-five adult Wistar rats were randomly assigned to one of two groups. The Achilles tendon of each rat was transected 5 mm proximal to its insertion to the calcaneus. All Achilles tendons were then repaired using modified Kessler methods. A single dose (5000 U/kg) of intraperitoneal erythropoietin (EPO) was administered to group I. Group II was a control group and did not receive an EPO injection. Four rats from each group were sacrificed at 1, 3 and 6 weeks after injection. Histopathological assessments were performed by observers blinded to the treatment. Results: Groups I and II showed a similar increase in fibroblast cytoplasmic content and fibrillar collagen in the extracellular matrix. Collagen deposition, cellular proliferation, number of lipid vacuoles and capillary increases were similar between the groups. Conclusion: Evidence from this study has shown no direct effect of a single systemic high dose of EPO on the histological properties of the Achilles tendon in rats. Cite this article as: Köker Y, Armangil M, Karaduman M, Yücel Tenekeci G, Acar B, Akan B. Investigation into the effect of systemic single high-dose erythropoietin on the healing of achilles tendons in rats. Acta Orthop Traumatol Turc., 2022;56(6):357-360.

Objective: This study aimed to evaluate how single-leg weight-bearing and double-leg weight-bearing radiographs affect knee osteoarthritis assessment and treatment planning. Methods: Fifty orthopedic physicians were asked to assess the knee radiographs of 10 female patients (mean age: 68 ± 6.6 years) presenting with knee pain. The radiographs were obtained in both double-leg and single-leg weight-bearing positions. Physicians were asked to determine the appropriate treatment plan (conservative management, unicondylar knee replacement, or total knee replacement). If they opted for surgical intervention, they were further asked to specify which prosthetic material they required to be available during surgery (a unicondylar knee prosthesis, both unicondylar and total knee prostheses, a total knee prosthesis, both total and revision knee prostheses). Treatment plans based on double-leg and single-leg weight-bearing radiographs were compared. Results: Conservative management was more frequently selected based on double-leg weight-bearing radiographs (P < .001). In contrast, the requirement for additional surgical materials was significantly higher for single-leg weight-bearing radiographs (P < .001). Specifically, 53.6% of physicians preferred having both total and revision knee prostheses available based on double-leg weight-bearing images, compared to 64.2% for single-leg images. Moreover, 31.2% of physicians upstaged their treatment plans after reviewing single-leg radiographs. Additionally, 13% of physicians opted for a total knee prosthesis based on double-leg weight-bearing images, whereas this proportion increased to 29% with single-leg weight-bearing images. Conclusion: Single-leg weight-bearing radiographs prompted more invasive treatment decisions, highlighting their clinical utility in detecting pathology that may influence surgical planning. Level of Evidence: Level IV, Diagnostic StudyCite this article as: Bozduman Ö, Köker Y, Ozturk M, Tuncay İ, Akan B. Impact of single-leg versus double-leg weight-bearing radiographs on surgical decisionmaking in knee osteoarthritis. Acta Orthop Traumatol Turc., 2025;59(5):274-279.

Background and Objectives: Courier-operated motorcycles and mopeds have become increasingly visible in urban traffic, raising concerns about injuries among both couriers and pedestrians struck by courier-operated vehicles. The study period coincided with the COVID-19 pandemic; however, this study was not designed to evaluate the effect of the pandemic on courier-related injuries. This multicenter retrospective study aimed to describe hospital-based injury patterns, injury severity, treatment requirements, complications, and mortality among selected courier-related casualties, including motorcycle couriers and pedestrians struck by courier-operated motorcycles or mopeds. Materials and Methods: This retrospective multicenter observational study included courier-related traffic casualties identified between 1 March 2020, and 1 June 2022, through nine hospitals in İstanbul and Ankara and, for fatal courier cases, linked emergency medical service and hospital records. The primary clinical cohort consisted of injured couriers and pedestrians evaluated or treated at participating hospitals. Linked prehospital and early fatal courier cases were analyzed separately for mortality-related and mechanism-specific fatality analyses. Injury severity was assessed using the New Injury Severity Score. Treatment was classified as conservative or surgical, including both fracture fixation and soft-tissue procedures. Results: A total of 857 courier-related traffic casualties were identified, including 491 couriers and 366 pedestrians. Among couriers, 111 fatal cases were verified through linked records. Clinical treatment and follow-up analyses were restricted to 380 hospital-treated surviving couriers and 366 pedestrians with available clinical records. In this selected hospital-treated courier cohort, multiple fractures, open fractures, higher injury severity scores, surgical treatment, and complications were more frequent than among pedestrians. All hospital-treated surviving couriers included in the orthopedic trauma cohort underwent surgery, reflecting the orthopedic trauma-based case-identification process, whereas most pedestrians were treated conservatively. Conclusions: Among this selected hospital-based cohort, courier casualties identified through hospital, trauma referral, emergency, forensic, and linked fatal-event records showed a more severe clinical profile than pedestrians evaluated after being struck by courier-operated motorcycles or mopeds. These findings should be interpreted as hospital-based injury-severity patterns rather than population-level estimates of accident incidence, relative injury risk, or public health burden.