The American Medical Association defines shin splints as “pain and discomfort in the leg from repetitive running on hard surfaces or forcible use of foot flexors. With that clear as mud definition, let’s try and make some sense of the injury.
The most common shin splints that I see during leg assessments are Posterior Shin Splints.
The job of the posterior tibial tendon is to support the arch of the foot. The muscle lies on the medial or inside part of the lower leg. As the foot arch drops during the weight bearing phase of your run, the tendon is tugged downward. This in turn pulls on the tibialis posterior muscle. It is the overuse of this muscle that then leads to the injury.
Three types of inflammation can happen as the muscle is tugged down.
1) Tendonitis, an inflammation of the tendon and/or tendon sheath (tenosynovitis).
2) Myositis, or an inflammation of the muscle itself.
3) Periostitis, or inflammation of the perisoteum, which is the covering of the bone.
In my experience, most runners end up with Periostitis. Small tears occur in the sheath that connects the bone to the muscle. This particular inflammation is exquisitely painful as nerves get stuck in the perisoteum lining. This type of injury produces levels of pain that are more akin to dental nerve pain instead of muscle pain.
What causes it.
1) The injury very often happens to younger runners, and is also prevalent in soccer, rugby, tennis and netball players.
2) The athlete needs to have his/her rate of pronation assessed. We do this as part of our leg assessment. Correct shoes need to be prescribed accordingly.
3) A lower foot arch, or a high yet more flexible foot arch will also predispose the athlete to the injury. As weight is placed over the foot, the Navicular bone drops, pulling on the tendon and hence the muscle. Your running shoe specialist store should be able to advise on which shoe will combat this. Pearl Izumi also make an insert that can be useful in walking shoes, rugby, soccer, tennis shoes e.t.c.
What cures it.
1) The trusty RICE formula will be your first stop in recovery. Rest, Ice, Compression and Elevation.
2) Get a proper pronation assessment done. We are able to accurately measure your rate of pronation.
4) You will need to strengthen your tibialis posterior muscle. Exercises can be prescribed to accomplish this.
5) Reduce your training and be very careful not to push too hard on down hills.
6) I am not convinced that physio is that effective when it comes to shin splints.
7) Place arch supports in rugby, tennis, netball shoes.
8) Should pain continue you should go for an x-ray, as you could be dealing with a stress fracture.
9) Get your running gait analysed as an overstride with heel strike will exacerbate the problem.