Hamstring injuries are the most prevalent muscle injuries in sport. Symptoms can be particularly prolonged, healing response poor, and the risk of re-injury high.Carl Askling (Karolinska Institute, Stockholm) has been trialling a new way of categorising these injuries, thinking about them as high-speed running or stretching types. He explains to Karim Khan how these types can be diagnosed and the different treatment and monitoring they require. He also describes how to assess athletes post hamstring injury for return to sport.See also:High-speed running type or stretching-type of hamstring injuries makes a difference to treatment and prognosis http://bit.ly/15Dzv8aHamstring strain injuries: are we heading in the right direction? http://bit.ly/LfwK2IHamstring issues in sports: still a major clinical and research challenge http://bit.ly/JTzgb7February’s BJSM has a special focus on hamstring injuries, so there’s even more related content in the issue and on the website.