Patellar & Quadriceps Tendon Rupture

Typically occur with a fall onto a knee that is partially flexed while the quadriceps muscle is forcibly contracting to break the fall. Patellar tendon ruptures typically occur in younger patients (< 40 years of age) and are frequently associated with sporting activities. Quadriceps tendon ruptures usually occur in patients > 40 years of age and are three times more common than patellar tendon ruptures.






ITE 2014 18. An 84-year-old male is walking across the street and has to hurry to avoid oncoming traffic. He suddenly develops extreme pain in his knee and falls down, and has to be carried to the sidewalk. The following day he comes to the emergency department. He is comfortable when placed in a knee immobilizer, but is very tender just above the patella. He can bend his knee but when he tries to straighten his leg it is so weak that he cannot move it at all. Radiographs of the knee are shown below.
What is the most likely diagnosis?

A) Patellar tendon rupture
B) Quadriceps tendon rupture
C) Tibial plateau fracture
D) Patellar subluxation
E) Lumbar radiculopathy