Shin splints, or medial tibial stress syndrome, is a very common condition. It is pain that runs along the shinbone, the long bone in the front of your lower leg (called the tibia). Shin splints aren’t a single medical condition. Instead, it’s a symptom of an underlying problem. The pain is the result of an overload on the shinbone and the connective tissues that attach your muscles to the bone. The causes are varied: flat feet, running, dancing, increased intensity of training, stress fractures (tiny hairline breaks in the bone), and a change of training surface (i.e., track to asphalt) can all be causes.