Shin splints is the general term given to pain experienced in the shin area of the leg and is not a specific diagnosis, but rather a convenient term to describe a number of possible physical processes at work; most commonly associated with the tibia. The tibia and fibula are the two leg bones between the knee and foot; the fibula is on the outside of the leg and much thinner than the tibia which sits on the inside of the leg. Pain in this area is most commonly caused by stress to the muscles, tendons or ligaments connected to the tibia. This stress can be caused by an increase in intensity or duration of exercise, or in athletes who endure a lot of shock to the legs; for example, marathon runners. Pain associated with this condition is called medial tibial stress syndrome, the attachment point on the tibia for the soleus and tibialis posterior muscles. This is half way between the knee and the foot on the inner surface of the tibia. In addition to marathon running, and dramatic exercise increases, the shape and locomotion of your foot can cause this syndrome. If you overpronate; your foot flattens out too much when standing upright, your foot will roll inwards placing stress on the muscles and tendons attaching to the tibia.
Another cause of shin splints is a stress fracture in the tibia. Unlike acute fractures that happen with impact stress and are instantaneous – breaking a leg skiing or falling; or breaking a bone in a car accident – large, instant traumas, stress fractures are usually caused by low forces acting on a bone over a long period of time. Also known as fatigue fractures, these breaks occur in athletes who do a lot of running and jumping on hard surfaces; dancers and runners.
Undiagnosed shin pain can be caused by Compartment syndrome. If you look at a cross section of the muscles and bones below the knee, you will see different pockets with the various muscles that make up the lower leg – these pockets, or compartments can contain one or several different muscles wrapped in fascia. Think of fascia like connective tissue shrink wrap surrounding your muscles. If, in the course of training, one of these muscles becomes too big for its compartment, it will cause stress and pain in the surrounding tissue. This is one cause of compartment syndrome. Another cause is swelling or bleeding resulting from a traumatic event.
Permanent treatment usually involves surgery – splitting the fascia; followed by careful rehabilitation. Short term treatments involve rest, physiotherapy and possibly orthotics.
My standard disclaimer – I am not a doctor, nor should any of the above information be taken as medical advice. I provide the above for informational interest. If your reaction to the above is “huh”, or “interesting”, my job is done.