Decreased pain threshold in children with growing pains

To investigate whether children with recurrent musculoskeletal pain termed growing pains (GP) have lower pain thresholds than children without GP.

We measured the pain threshold of 44 children with GP and 46 controls. Pain thresholds were measured by use of a Fisher type dolorimeter with pressure applied to areas associated with increased tenderness in fibromyalgia (FM), control points, and anterior tibia, the usual region of pain in children with GP. Unpaired Student's t test and chi-square tests were used to compare the pain threshold and number of tender points in patients and controls.

The pain threshold in characteristic tender points of FM, control points, and anterior tibia in the children with GP was significantly lower in children with GP (3.5 +/- 0.6 kg/cm2 in GP versus 4.0 +/- 0.7 in controls, p < 0.001, 3.8 +/- 0.7 versus 4.4 +/- 0.8, p = 0.005; 5.1 +/- 1.1 versus 5.9 +/- 1.5, p = 0.004). Children with GP had a significantly greater number of tender points in response to an applied pressure of 4 kg/cm2.

Children with GP have more tender points and lower pain thresholds than children without GP indicating that GP may represent a variant of a noninflammatory pain syndrome in younger children.