The pressure pain threshold (PPT) of certain muscles in children suffering from recurrent abdominal pain of non-organic origin. An algometric study.

The origin of recurrent abdominal pain of "non-organic origin" is believed to be psychogenic in most cases. But the pathogenesis of the pain itself is unknown. To test the hypothesis that recurrent abdominal pain of non-organic origin is related to increased pain sensitivity in the myofascial elements of the abdominal wall itself, an investigation of pain pressure threshold of the abdominal wall, close to the umbilicus, was carried out. Altogether 140 children in the fourth school grade, approximately 11 years old, were tested for pressure pain threshold. Two groups were constituted: one without pain symptoms (no recurrent abdominal pain, chest pains or headache (n = 50)) and one with recurrent abdominal pain (n = 49). The pressure pain threshold differed significantly (p < 0.0001). To support the hypothesis that recurrent abdominal pain is a part phenomenon of a specific pattern of muscular tension and tenderness, the pressure pain threshold was tested in five other muscles, with significant results.