Hip and leg pain in children: When to worry

Hip and leg pain in children is always worrisome with one exception: growing pains.  Leg pain that is the result of growing pains is a benign condition that resolves without any specific intervention.  The diagnosis of growing pains is given when the several criteria listed below are met.

Criteria for the diagnosis of growing pains:

1. Pain occurs during the night and disappears by morning.

2. Pain occurs in both limbs at the same time.

3. Pain is not associated with the joints.

4. Pain is not caused by walking and does not cause a limp while walking.

5. Pain is not associated with any tenderness to the touch, redness or local swelling.

6. Pain occurs in the absence of systemic signs or symptoms of disease, such as fevers, weight loss,

easy bruising or bleeding, or night sweats.

7. Pain occurs between the ages of 4 and 14.

If a child has hip and/or leg pain that does not meet these criteria, then other possible causes must be considered.  There is a very long list of possible causes.  This is because leg pain can come from the joints, bones, muscles, tendons, and even the fascia.  It can be due to an infiltrative process, inflammatory process, infectious process, traumatic event, metabolic disease, nutritional deficiency, and more.  Pain can also be referred.  For example, problems with the hip joint can manifest as referred pain to the thigh or knee.

Some of the more common causes of lower extremity pain are listed here:

Developmental Dysplasia of the Hip - Misalignment of the hip joint, present since birth.

Transient synovitis - Usually following a viral upper respiratory illness. Resolves without treatment.

Accidental Trauma - Hematomas, sprains, fractures. Uncommon in children who are not yet walking.

Nonaccidental trauma - Bruising in unusual places or fractures midway through long bones.

Reactive Arthritis - Usually following episode of infectious diarrhea in children.

Septic Arthritis - Often a red, hot joint. Ruled out with aspiration of the joint fluid.

Juvenile Rheumatoid Arthritis - Several different forms of JRA with many treatment options.

Leukemia - Most common malignancy of childhood.

Osteomyelitis - Often following an overlying skin infection with staph or strep.

Slipped Capital Femoral Epiphysis - Most common in obese prepubescent males.

Osgood-Schlatter Disease - Most common in young male athletes

Legg-Calve-Perthes Disease - Idiopathic avascular necrosis of the femoral head.

Osteosarcoma - Usually localized to the end of long bones.

Ewing’s sarcoma - Most common in males 10 to 20 years old, pelvic and proximal long bones.

Henoch-Schonlein Purpura - Associated with abdominal pain and lower extremity rash.

Lyme disease - May have “bulls eye” rash, fever, headache, malaise.