Q: My son is very active, playing hockey and karate, plus lots of school activities. For the past two weeks, he has been complaining of hip pain. Should I keep him out of sports until the pain goes away?
A: With childhood obesity rates on the rise, many parents are enrolling their kids in sports so that they get regular physical activity and some extra fun in their week. It is true that children heal faster than adults when they become injured. Since they recover so quickly, persistent pain in kids stands out and should not be ignored.
ABOUT THE HIP
The hip is a very mobile, weight-bearing, ball-and-socket joint. The ball part is from the femur (thigh bone) and the socket part from the pelvis, called the acetabulum. Both the ball and socket sides are covered by cartilage, a smooth cushioning for the joint that allows for the ball and socket surfaces to touch with minimal friction. The ball is held in the socket by supportive ligaments.
DIFFERENT AGES, DIFFERENT PROBLEMS
Adults often see their physician concerned about the possibility of osteoarthritis in their hip joint. Osteoarthritis is not common in children or young adults and different ages in childhood can produce different types of hip problems. Even from birth, before a child leaves the hospital, hips in infants are checked for congenital hip dysplasia, in which the hip joint does not form properly and can dislocate. Children have growth plates, which means areas of their bones are not solid yet. These growth plates are more susceptible to injury than solid bone.
Here are some the hip conditions that we see in children:
-- Synovitis -- an inflammation of the joint, can also be an infection in the joint. This synovitis can be a one-time occurrence or part of a general arthritic condition, even in young children.
-- Legg-Cathes-Perthes disease -- this condition occurs in the 4 to 9 age range when there is a lack of blood supply to the hip joint and the ball or head of the hip joint becomes flattened.
-- Slipped Capital Femoral Epiphysis -- the ball part of the hip joint slips off the growth plate. This is more likely to happen in the 10-16 age group and in overweight males.
-- Tumors -- both cancerous and non-cancerous can occur over a range of ages in the area near the hip.
-- Stress fractures -- can occur in the thigh bone or pubic bone, close to the hip, in teenagers or younger children training in a sport such as gymnastics, dance, figure skating or running.
-- Hip muscle strain -- muscles that flex (bend) the hip, such as the iliopsoas or rectus femoris, can slide over other structures (the "snapping" hip) or the muscle can be pulled off its attachment to bone (called an avulsion).
Not all hip trouble starts with pain; sometimes a change in the way a child walks shows up first. Regardless, limping or pain in the hip area, groin, thigh or knee should always be checked out by your physician. With some hip problems, clicking or snapping may be a feature. Persistence of symptoms is key. If your child has complained of symptoms for more than a week, it is a good idea to get a hip assessment. If they have a sudden incident or injury, they should seek medical attention as soon as possible.
A good history and physical examination that includes the knee, hip, pelvis and lower back is required to assess a hip problem in a child. Unlike some other bony problems, it is common to order X-rays for hip symptoms in children. Sometimes, other tests such as bone scans or MRI scans are ordered. The treatment really depends on the diagnosis. Some problems such as fractures require taking weight temporarily off the affected limb and other conditions may require surgery. An exercise program is still possible for many hip problems but the program will usually involve low to non-weight-bearing activities as a starting point.
Overall, it is always wise to get hip pain in kids checked out. It is unlikely to be a "growing pain" and demands medical attention. When you know more specifically what the problem is, you will be able to plan future activities, armed with a lot of hip knowledge.
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