[Cyriax's syndrome. A cause of diagnostic error in abdominal pains]

The slipping rib syndrome is characterized by upper abdominal pain due to irritation of the intercostal nerve by incomplete dislocation of the costal cartilage of the 8th, 9th, or 10th ribs. Twenty-three new cases are reported and the literature is reviewed. Diagnosis is only clinical. The pain is precipitated by movement and certain postures; it is faithfully reproduced by pressure on one particular point of the costal margin and is relieved by local injection of an anaesthetic. Pain from a slipping rib is usually attributed to visceral causes, which is a source of diagnostic errors.