Primary hyperparathyroidism presenting as delayed fracture union

We describe a case of delayed union in a tibial fracture secondary to primary hyperparathyroidism. A closed intra-articular proximal tibia fracture was stabilized with a hybrid external fixator. At 5 months clinical and radiological evaluation failed to demonstrate evidence of fracture healing. Fixation was stable and inflammatory markers ruled out infection. Further questioning revealed symptoms of anorexia, nausea and constipation. Plasma biochemistry showed an elevated corrected calcium and parathyroid hormone concentration. Further investigation included a sestamibi scan which confirmed a diagnosis of hyperparathyroidism secondary to a parathyroid adenoma. Six weeks following partial parathyroidectomy the fracture site was pain free, non-tender and the fracture had united radiologically. In cases of delayed-union, once an infective cause has been excluded with a mechanically stable fracture, other causes of delayed union like primary hyperparathyroidism should be ruled out.