Shin splints tend to be developed due to excessive repetitive running or jumping.
The tibia is also referred to as the shin . “Shin splints” is a classical disorder name; the disorder is also called medial tibial stress syndrome, anapeiratic tibial pain, and it has inconsistent content with a broad interpretation. Therefore, this section mentions only the disorder caused by inflammation of the periosteum or muscle tendons, excluding stress fractures and compartment syndrome.
Cause and mechanism of onset
This is one of the overuse disorders. And it is more likely to be developed according to excessive repetitive running or jumping. The triggers of development would be excessive amount, time and content of exercise, changes in numbers of days or movement form, hard road surfaces, thin and stiff shoes (heel wear), morphological abnormalities of the lower extremity (e.g. bow legs, pronated feet and flat feet), reduced flexibility of the triceps surae, reduced flexibility of the hip, knee and ankle joints, and limited range of motion of ankle. Rapid increases in physical activity especially on new members have harmful effect. It is recommended to improve the situation quickly for those who have something in mind. The clinical state is considered to be caused by reduced flexibility due to fatigue of the medial leg muscles, and particularly micro damage in tibia (periostitis) developed by traction of the periosteum overlying the tibia by the tibialis posterior muscle mainly involving the soleus muscle and the attachment of the flexor digitorum longus muscle causing traction, resulting in pain in the medial lower leg (Fig. 1 and Fig. 2). Runners often suffer from the disorder with at the rate of 20 to 50% of them.
Figure 1 and 2: Causes of shin splints
Tenderness, exercise pain, and swelling gradually developed on the medial side of lower leg (mainly one-third of the medial border of the tibia, about 12 to 20 cm above the medial malleolus of the tibia as a guide) are the main symptoms. Resistance exercises of the flexors of the foot increase the pain.
The severity of symptoms is as categorized as follows.
Stage 1: Being painful but resolved with warm-up
Stage 2: Being painful and resolved with warm-up, but becoming painful near the end of the sports activity
Stage 3: Having pain at all times during sports activities but no problem in daily activity
Stage 4: Local pain is present at all times and interferes with daily activity
As it is inflammation of the periosteum, X-rays usually find no changes. If the symptoms persist, re-examination is required. In this case, the diagnosis is changed to stress fracture if osseous changes are developed later. However, MRI may show thickened hyperintense changes (white) in the periosteum of the tibia.
Causes of lower leg pain include stress fractures of the tibia and compartment syndromes. Indeed, it is difficult to distinguish it from the initial image of a stress fracture, but the initial treatment would be the same. Tendinitis at the insertion site would be broadly similar.
Treatment and rehabilitation
It is recommended to limit the causes listed above such as the amount of exercise. In the acute phase, local rest (the stop of running), icing (ice massage) and anti-inflammatory analgesics are used. Plantar plates are used for shape correction.
During the painful acute phase, make sure to stop running completely. However, even with local rest period, the person may perform swimming, exercise bike (make sure to step on a pedal with the heel), stretching the lower extremity mainly on hip joint, ankle joint and Achilles tendon while avoiding doing weight-bearing exercise on the lower extremity. Once spontaneous pain or walking pain disappears, the person may perform gathering towel by the toe and gentle tube training of the ankle. After obvious tenderness (the pain when pressing; not spontaneous pain) disappears, start from walking, followed by mild running (be sure to avoid running on hard roads) if stepping and jumping on both leg do not cause pain. However, caution should be exercised that the person may have pain again if the amount of practice is increased rapidly.