Patellar tendinopathy: an overview of prevalence, risk factors, screening, diagnosis, treatment and prevention

Abstract

Patellar tendinopathy (PT), or jumper's knee, is an overuse injury that occurs in professional, as well as recreational, athletes. This condition is a noncontact injury, typically characterized by gradually increasing pain in the patellar tendon. It is prevalent in participants of several sports, but it occurs mostly in jumping sports. The diagnosis of PT is primarily clinical; however, imaging techniques can be useful as well. Risk factors differ between sexes, playing conditions, the kind of sport, playing level and personal characteristics. Screening is an essential tool to assess PT. This condition affects athletic performance and often persists for years. The use of preventative methods is imperative because of the persistence of this condition, especially in elite athletes who sometimes end their career after long and failed treatments. There are a wide variety of treatment and rehabilitation options available, the majority of which are non-operative, such as eccentric exercises, cryotherapy, platelet-rich plasma (PRP) injections, and anti-inflammatory strategies. If conservative treatment fails, surgery is the next most preferable step. Even though there are many surgical treatment methods, there is no clear evidence on what is the most effective approach to address PT. Taking this into consideration, as well as the extent of this clinical entity, novel therapeutic techniques, as well as screening and prevention methods, are expected to emerge in the near future.

Keywords: Jumper’s knee; Patellar tendinopathy; Patellar tendon.

Fig. 1

Ultrasonography images of the left patellar tendon, in a middle-aged elite athlete with persistent anterior knee pain. a Longitudinal B-mode image showing the inhomogeneous echogenicity in the distal anterior tendon in keeping with degeneration (short arrows) and microtears in the posterior aspect (long arrows). b On the right side of the image, the normal right patellar tendon is shown for comparison (arrows). c Longitudinal color Doppler image shows florid neovascularity in the degenerated foci (arrows). (Courtesy: Dr. G. Kakkos and Prof. A. Karantanas, Dpt. of Medical Imaging, Heraklion University Hospital)

Fig. 2

a T2-weighted MRI image of the left knee, in a young elite athlete with PT symptoms. It demonstrates an increased signal interposed in the patellar tendon. b T2-weighted MRI image of the left knee, in a young elite athlete with PT symptoms, showing a free bone formation in the mass of the patellar tendon

Fig. 3

This figure shows an athlete performing an eccentric decline squat