Tendon disease and adjacent bone erosion in dialysis patients.

Six out of 169 patients on maintenance haemodialysis showed spontaneous tendon rupture. In all six, bone erosion had previously been observed at the site of tendon insertion. In a further 13 patients whose tendons had never ruptured, marked bone erosions at the sites of tendon insertions were also observed. Both groups of patients, with tendon rupture and with bone erosion only, showed significantly greater blood alkaline phosphatase and parathyroid hormone levels than all the others. Moreover, osseous radiological findings of hyperparathyroidism were more marked in all these 19 patients than in the others. Bone erosion at the site of tendon insertion may be a true and specific sign of tendon disease in patients with uraemia. Our series shows that it bears a close relationship to hyperparathyroidism, and suggests that tendon disease is a specific sign of severe secondary hyperparathyroidism in patients with uraemia.