by Dr. Rick Cunningham
Hip injuries are on the rise in adolescent athletes. This is due to the increasing number of young athletes participating in organized sports as well as advances in technology that have improved clinicians diagnostic ability.
There are several risk factors for hip injuries in adolescents. First of all, with puberty, limb length increases more than limb mass resulting in a temporary decrease in coordination while also causing some muscular imbalances. Typically, young athletes become dominant in their hip flexor and quadriceps musculature while having less strength in their hamstrings and gluteal muscles, which along with their IT band, then become tight and painful. In addition, open growth plates in these young athletes are relatively weak and are less able to withstand the repetitive forces that ski racing and other sports sometimes demand.
WHERE IS THE PAIN COMING FROM?
It is important to first have patients localize where the pain is coming from. If the pain is located in the groin and they grasp their hip with the so-called C sign, then the problem may be coming from within the hip joint and possibly from a labral tear. If the pain is located over the side of the hip, it is more likely coming from outside the hip joint, usually from hip bursitis or tendonitis. If the pain is localized in the buttock region, then the pain is usually coming from the low back or sacroiliac joint.
When I see an injured athlete in the office, I like to obtain a thorough history and do a good physical exam. I like to check the athleteâs gait, as well as assess hip joint range of motion and hip stability. Furthermore, a simple radiograph of the hip is important to check and see if the injured athlete has had any developmental problems with their hip joint.
Some people are born with hip dysplasia and an xray will show if the hip joint did not develop normally such that there is abnormal stresses on the cartilage of the hip joint. An MRI is useful if there is not a bony problem, but rather a soft tissue problem. An MRI can show if there is possibly an area of dead bone or necrosis in the hip, a labral or cartilage injury, as well as showing if there is an inflamed or torn tendon about the hip. Unlike a CT scan, with an MRI there is no radiation so this is a very safe test to perform on a young person who is still developing.
THE LABRAL TEAR
A labral tear is a fairly common cause of hip pain in a young athlete. The labrum is a tough, rubbery like ring of fibrocartilage that attaches to the edge of the hip socket. It acts to deepen the hip socket, creates a suction seal between the femoral head and socket of the hip, and acts to reduce the contact pressure between the femoral head and the socket. The labrum can be injured as a result of increased motion between the ball and socket.
Labral tears can also occur from repetitive flexion and rotational stresses on the hip joint, usually in combination with some bony impingement where the top part of the femur bumps up against the edge of the labrum and the edge of the hip socket.
In a young athlete with a labral tear, they usually complain of sharp pain, which is usually worse during or after playing sports. They may also complain of a catching sensation in the hip. If the diagnosis of a labral tear is made, I recommend resting the hip and doing some specific physical therapy. A small number of these patients may eventually require hip arthroscopy with labral repair and removal of any bony prominence that may have contributed to the tear.