Runners with shin pain are usually suffering from either shin splints - a catch all term for lower leg pain - or compartment syndrome - a build up of pressure in a muscle compartment of the leg.

Shin splints is a catch all term for a number of conditions that can cause lower leg pain. The lower leg comprises of four muscle compartments each surrounded by a thin restraining membrane of fascia. The muscles and fascia are attached to the bones of the lower leg (tibia and fibula).

Symptoms Generally, pain initially occurs in the lower leg the morning following activity and settles. However, the pain gradually becomes more permanent until it limits the level of activity. If a stress fracture has occurred this will tend to be painful during activity and settles quite quickly on rest.

Cause

• Shin splints are caused by an overload of the legs.
• Increased levels of running, poor footwear, hard surfaces, poor foot movement or tight muscles can all overload the legs.
• If this happens, the muscles will initially work harder to try to help control motion.
• This can cause them to become sore because of inflammation of the muscle (myositis) or tendons (tendinitis).
• With continued activity, the muscles will place stress on the fascia, which will pull at its attachment on the bone.
• This can cause the edge of the bone to become extremely tender.
• With continued activity the softer, outer layer of bone (periosteum) will become inflamed (periostitis).
• In severe cases, a stress fracture may occur which is a small break in the bone often not visible on X-ray.

Self help

These conditions may all respond to a combination of modifying activity, running on softer grounds and improving footwear. Get advice immediately if symptoms develop.

Treatment

Physiotherapy, including stretching and strengthening exercises and the fitting of customised orthoses (shoe inserts) may be necessary.

Average recovery time

Depending on severity, 2 weeks to long term.

Prevention

Good stretching, footwear and training programme. Avoid training on cambered roads and beaches, running the same route all the time and suddenly increasing your mileage.

Compartment Syndrome
This is sometimes categorised in the loose term 'shin splints' but is a build up of pressure within a muscle compartment of the leg causing pain.

Symptoms

Again pain will be felt in the lower leg possibly during or at the end of a long run.

Cause

• In some people, either the muscle bulk is too large or the restraining fascia is too tight.
• If the restraining fascia is too tight the normal fluid that is produced in a muscle during exercise (due to the metabolism of the muscle) causes a build up of pressure within the compartment that causes pain.
• This gets to a level that prevents activity but will then take a few minutes to settle.
• There are usually no residual symptoms the following day although as shin splints can exist at the same time as a compartment syndrome, pain may be felt because of shin splints.

Self help and treatment

The only effective self help is to stop running. Other than modifying activity levels, there are few treatments that are effective for compartment syndrome other than a surgical release of the tight fascia. If you think you may have compartment syndrome it is best to seek professional help as soon as possible.