Over the last few months I have seen an increasing number of hamstring injuries which has inspired to me write this blog. Hamstring pulls or strains are one of the most common sports-related injuries. The hamstring, a group of 4 muscles in the back of the thigh, can be felt stretched as you bend forward to touch your toes. Three of the four hamstring muscles, the semitendonosis, semimembranosis, and long head of the bicep femoris, cross both the hip and knee joint and are true hamstring muscles. At the top, these muscles have a common attachment to the ischial tuberosity (a bone at the bottom of the pelvis), and at the bottom these muscles attach to the tibia and fibula (bones below the knee). The other hamstring muscle, the short head of the bicep femoris, only crosses the knee joint.

There are two main types of hamstring injuries, and each affects a different part of the hamstring group. The injury I most often see in my clinic is a strain that occurs at the tendinous insertion on the ischial tuberosity at the pelvis. This commonly occurs in tri-athletes, and marathon runners who will complain of pain in the lower buttock region that increases with sitting and when the injured leg strikes the ground. The second type is more in younger athletes is caused by a sudden motion, such as an explosive sprint, jump, or a kick. In this type of injury, the strain occurs at the muscular portion of the hamstring, resulting in pain, swelling, and bruising in the middle of the back of the thigh.

An understanding of the biomechanics of running makes it easier to understand how these injuries occur and how to prevent them. There are two phases of running: the stance phase and the swing phase. The stance phase consists of foot strike, mid stance, and toe off; and the swing phase consists of follow through, hip flexion and leg descent. During the eccentric contraction, muscle fibers will slowly elongate to slow down a particular motion, while a concentric involves shortening of the muscle fibers to lift an object or move a limb in a particular direction. During leg descent and foot strike, the pelvis flexes forward and the leg extends, the hamstring muscles are eccentrically contacted to slow both of these particular movements. When the eccentric load exceeds the strength of the muscle fibers, tearing of the hamstring fibers occurs, resulting in a strain injury.

The Advanced Injury Treatment Center utilizes a comprehensive treatment approach to hamstring injuries. Deep tissue procedures including Active Release technique and Graston Technique are used to free up soft tissue motion of the hamstrings and surrounding musculature. Implementation of proper strength and flexibility training of the hamstring musculature and the nearby muscles surrounding the pelvis and thigh will reduce the risk of injury. Focus on strengthening the abdominal and gluteus maximus musculature is important in the prevention of a hamstring strain because these muscles aid the hamstrings in decelerating flexion of the pelvis during heel strike. Flexibility of the hip flexors and low back musculature is also important in the prevention of a hamstring strain injury. Tight hip flexors and low back musculature causes excessive flexion of the pelvis during foot strike placing increasing strain on the hamstrings. Tightness in these muscles also inhibits strengthening of the gluteus maximus and abdominal musculature. Advice on how to progress training runs more appropriately also aids in reducing the risk of injury.