Published online Sep 18, 2018. doi: 10.5312/wjo.v9.i9.180
Peer-review started: May 8, 2018
First decision: June 5, 2018
Revised: June 18, 2018
Accepted: June 28, 2018
Article in press: June 28, 2018
Published online: September 18, 2018
The spontaneous and simultaneous rupture of both quadriceps tendons is uncommon and has rarely been reported in the literature. The current case involves a 43-year-old man with end-stage renal disease requiring hemodialysis for the past 20 years. The patient experienced bilateral knee pain and swelling and was unable to bear weight. Physical examination revealed bilateral quadriceps tendon defect above the patella and loss of active extension. Although plain radiographs of both knees showed no fracture or widening of the joint space, an inferiorly positioned patella was observed. Ultrasonography of the knees revealed a quadriceps tendon defect at the upper edge of each patella, while MR imaging revealed a tear in each quadriceps tendon from the superior poles of the patella. The patient then underwent surgical correction wherein the tendons were repaired using sutures passed through drill holes in the patella. The knees were immobilized with splints for 4 wk before starting physiotherapy. The patient subsequently regained full functional activity within 1 year.
Core tip: Spontaneous bilateral quadriceps tendon rupture is uncommon, while the symmetry of physical findings may make the diagnosis even more difficult. Testing the extensor mechanism must be an essential part of every knee examination. Early diagnosis and surgical repair are associated with the best outcomes. The most likely etiology of tendon ruptures in patients receiving hemodialysis is the fragility of the junction between the tendon and the bone resulting from long-standing and poorly controlled hyperparathyroidism.