CHAPTER 77
Quadriceps Tendinopathy and Tendinitis
Farshad Adib, MD; Christine Curtis, MD; Peter Bienkowski, MD; Lyle J. Micheli, MD
Definition
The quadriceps tendon is located at the insertion of the quadriceps muscle into the patella and functions as part of the knee extensor mechanism. Quadriceps tendinitis (or, as named in the more recent literature, tendinosis or tendinopathy) is an overuse syndrome characterized by repetitive overloading of the quadriceps tendon. The common mechanism of injury is microtrauma, in which the basal ability of the tissue to repair itself is outpaced by the repetition of insult [1]. Quadriceps tendinopathy often occurs in athletes participating in running and jumping sports as well as in persons who perform frequent kneeling, squatting, and stair climbing [2]. The superior strength, mechanical advantage, and better vascularity of the quadriceps tendon make quadriceps tendinopathy much less frequent than patellar tendinopathy [3].
Symptoms
Patients usually report an insidious onset of knee pain and may note painful clicking. Their chief complaint is usually “knee pain.” A burning sensation at the bone-tendon junction may be experienced [4
