Fig. 1

a, b Lymphocyte Transformation Test Response. The effect of various metals and PHA on the proliferation rate of patients’ and controls’ lymphocytes: mean lymphocyte response (SI) of each of the three patient groups compared to controls. Group 1 = patients scheduled for pTKA, labelling for a clinical history of metal allergy; Group 2A = TKA patients with pain and clinical signs of metal allergies; Group 2B = TKA patients with pain and no clinical signs of metal allergies; Group 3 = Control subjects. Metal concentrations: (a) = 0.1 mM; (b) = 0,01 mM. Asterisks indicate: (*) p < 0.05; (**) p < 0.005; (***) p < 0.0001