RT Journal Article SR Electronic T1 Hamstring injuries JF British Journal of Sports Medicine JO Br J Sports Med FD BMJ Publishing Group Ltd and British Association of Sport and Exercise Medicine SP e2 OP e2 DO 10.1136/bjsm.2010.081570.17 VO 45 IS 2 A1 N G Malliaropoulos YR 2011 UL http://bjsm.bmj.com/content/45/2/e2.10.abstract AB Lecture 17 Muscle injuries are among the most common, most misunderstood, and inadequately treated conditions in sports. According to some studies, muscle injuries account for 10–30% of all injuries in sport.1 Hamstring injuries are the commonest muscle injury in all sports. Hamstrings function is complex. Depending on leg positioning and relationship to the ground it can serve as a hip extensor, knee flexor and external rotator of the hip and knee. Long head receives innervations via a tibia portion of the sciatic nerve, the short head receives innervations from the common personal nerve. The mechanism of the injury is very important to know. Contraction injuries occurring during running at maximal or near-maximal speed primary involve biceps femoris, long head and they heal faster comparing to stretching injuries occurring in dancing or kicking and primary involving semimembranosus, proximal tendon.2 Various systems have been used to classify the severity of the injury. They classify them in three grades, as mild, moderate, severe, according to imaging findings, time to walk pain-free.3 Our Clinical classification is based on estimating the knee active range of motion deficit between the injured and the healthy side.1 Ultrasound is used to image the muscle lesion.4 Following this clinical classification we are able to decide for the treatment, to design the rehabilitation protocol to predict the time to full rehabilitation and to assess the reinjure rate. We must always keep in mind to differentiate common signs and symptoms of a hamstring strain injury compared to those referred to the posterior thigh from another source.5 Rehabilitation is one of the key points dealing with hamstring injuries. We as clinicians have to prescribe the right clinical application correlated to each healing process phase operative intervention is reserved only for severe injuries, such as complete rupture of the hamstring muscles, either at the insertion or at the origin (avulsion). The reinjure rate for hamstring injuries has been found to be 12–31% early return to sport and poor rehabilitation programme met with a high risk of reinjure according to our clinical classification. Objective clinical findings can provide an effective clinical tool to assess the risk of re-injury following acute hamstring muscle strains in elite track and field athletes.6 In terms of prognosis the following factors have been shown to require a greater convalescent period: injury involving a proximal free tendon, proximity of the injury to the ischial tuberosity, increased length and cross-sectional area of injury. Past history of hamstring injury is the main risk factor for the next injury.3 Being unable to walk at a normal pacepain-free within 24 h of injury was independent predictor of being unable to return to play in less than 4 weeks from the time of injury. Defining the severity of the injury enable us to assess the expected return to play timescale which is important in guiding rehabilitation and in team planning.6