THE pattern of injury in sport is remarkably similar across different sports and in different countries.

Lower-limb injuries, especially of the ankle and knee, back and shoulder are the most common.

However. sometimes it is the less common injuries which cause the most difficulty in diagnosis and treatment, frustrating for the athlete who only wants to know when he can get back to competition.

One such injury is to the hip.

While any sportsman or woman is at risk of hip injury from trauma or overuse, it is more common in certain sports such as running and cycling, and those such as football and hockey where quick changes in direction are common.

It is also an area where the likely diagnosis is often linked to the athlete's age - and their stage of skeletal development.

Very young children can present with a limp which may be a transient inflammation around the joint or the first sign of a longer-term problem such as Perthes disease.

In adolescence, when bony growth is taking place, there is a well-recognised condition which results in a "slip" at the growth plate and requires surgical intervention.

In the older age groups, arthritis of the hip is more prevalent, especially in those who are overweight.

There has been much debate as to whether repetitive running predisposes to arthritis of the hip.

On balance, in all but those who run extreme distances over many years, there appears not to be an increased risk.

In fact, many of us believe that maintaining an active lifestyle will reduce the risk and severity of developing arthritis.

What is also important is to avoid being overweight and ensure full rehabilitation from injury.

Hip pain in younger adults is often the most difficult to diagnose, with a long list of potential causes.

Those taking part in high-intensity sport are at greater risk of trauma. A direct blow to the hip will result in a local muscle or bony injury, including fractures.

Stress fractures of the neck of the thigh bone are an important cause of hip pain over a longer period of time.

Perhaps the most common causes of hip pain, especially in repetitive sports like running, are tendonopathy and bursitis.

The trochanteric bursa is a sac of fluid which lies on the outside of the hip bone which is usually easy to feel in thin athletes. It provides a cushion and lubricates smooth movement of the muscles around the hip.

Inflammation may result from increased intensity or frequency of exercise, and is often linked to biomechanical problems in the lower limb, especially the foot.

Like the shoulder, the hip is maintained in its socket by the surrounding soft tissue structures like muscles and ligaments.

Finally, it is important to remember many other conditions such as groin or hamstring problems, back conditions and even medical problems within the abdomen and the testes in men may present as hip pain, so a full examination is essential especially when the pain has been present for some time.

The National Stadium Sports Health and Injury Clinic is on 0141-616 6161 and www.sportsmedicinecentre.org