Simultaneous and spontaneous rupture of patellar tendon and contralateral quadriceps tendon in a patient with tertiary hyperparathyroidism: A case report

Introduction: Spontaneous bilateral ruptures of the extensor mechanism of the knee are rare injuries. Case Report: A patient presented with bilateral rupture of the extensor mechanism of the knee in which a tertiary hyperparathyroidism was previously diagnosed. Tertiary hyperparathyroidism was related to a long­term dialysis for chronic renal failure and on admission, the parathyroid hormone level was 2332 pg/mL. The patient underwent surgery of the both knees and a satisfactory function was achieved. Subsequently, a parathyroidectomy was performed which resulted in a correction of the parathyroid hormone level. Conclusion: Tertiary hyperparathyroidism must be ruled out in patients with chronic renal failure. On the other hand, patients with chronic renal failure and a known hyperparathyroidism need on going and effective management to prevent spontaneous tendon rupture. Clinicians can be aware that careful management of hyperparathyroidism can prevent this severe complication.