ORIGINAL PAPER Effect of curcumin on tendon healing: an experimental study in a rat model of Achilles tendon injury Ali Güleç 1 & Yılmaz Türk 1 & Bahattin Kerem Aydin 1 & Ömer Faruk Erkoçak 1 & Selim Safalı 1 & Ceyhan Ugurluoglu 2 Received: 2 January 2018 /Accepted: 4 June 2018 # SICOT aisbl 2018 Abstract Purpose This in vivo study aims to investigate the effects of curcumin which is recently developed for tendon healing using a rat Achilles tendon injury model. Materials and methods Eighteen male Wistar albino rats weighing 300–400 g were used in this study. Under anesthesia, Achilles tendon injuries were created and repaired surgically. Nine rats of the study group received curcumin (suspended in saline at a dose of 200 mg/kg orally) and eight rats of the control group received only saline solution by oral gavage for a period of 28 days. Animals were euthanized on the 28th post-operative day, and all the Achilles tendons were removed and transferred immediately for biomechanic and histological analysis. Results Macroscopically, all the tendons were fully healed. Total mean Bonar score was higher in the control group. When the parameters of Bonar score were analysed separately, tenocyte morphology, collogen, and ground substance scores were statis- tically lower than the control group (p = 0.03, 0.041, 0.049, respectively). Vascularity parameter did not show any statistical difference (p > 0.05). Of the nine biomechanical parameters, five of them (failure load, cross-sectional area, length, ultimate stress, strain) showed better results which were also statistically significant (p = 0.046, 0.027, 0.011, 0.021, 0.002, respectively). When the remaining four parameters were examined, the study group also had better results, but this difference was not statistically significant. Conclusion Curcumin had better results for total tendon healing not only histologically but also biomechanically. Curcumin could be an additional agent in the management of surgically repaired tendon injuries. Keywords Achilles tendon . Curcumin . Tendon injuries . Rat . Antioxidant Introduction Tendons are important for normal joint motion and stability. Injuries of the tendons are among the most common injuries of the body [1]. Tendon injuries are responsible for serious health care costs, which generally brings about restricted activity and individual morbidity [2]. Tendon healing process consists of three complex phases which are inflammatory, proliferative, and remodeling. Many factors have been studied for better tendon healing process such as stem cells, growth factors, and haemostatic agents [3–5]. But, there is not a perfect agent for shortening the healing process and lowering the complica- tions such as adhesions and poor mechanical properties. Still healing process of tendon injuries is a significant challenge for orthopaedic and plastic surgeons. Curcumin, a naturally occurring compound extracted from turmeric (Curcuma longa), shows strong antioxidant and anti- inflammatory activities. More than 7000 articles have * Bahattin Kerem Aydin bkaydin@yahoo.com Ali Güleç dr.aligulec@gmail.com Yılmaz Türk yturk9@gmail.com Ömer Faruk Erkoçak farukerkocak@gmail.com Selim Safalı selimsefali@gmail.com Ceyhan Ugurluoglu drceyhan@gmail.com 1 Department of Orthopaedics and Traumatology, Faculty of Medicine, Selcuk University, Alaeddin Keykubat Campus, 42130 Konya, Turkey 2 Department of Pathology, Faculty of Medicine, Selcuk University, Alaeddin Keykubat Campus, 42130 Konya, Turkey International Orthopaedics https://doi.org/10.1007/s00264-018-4017-5