One injection of platelet-rich plasma associated to a submaximal eccentric protocol to treat chronic jumper's knee
INTRODUCTION: Jumper's knee is a frequent chronic overuse syndrome of the upper part of the patellar tendon. Platelets contain lots of growth factors which could enhance the healing process of tendons.
METHODS: Twenty patients with chronic upper patellar tendinopathy were enrolled. Assessments were made before infiltration of PRP, and 6 weeks and 3 months after the infiltration, using a 10--point Visual Analogic Scale, clinical examinations with a pressure algometer, algofunctional scores (IKDC and VISA--P), functional assessments (isokinetic and optojump evaluations) and imagery (ultrasounds and MRI). The PRP was obtained with an apheresis system (COM.TEC, Fresenius). Six millilitres of PRP were injected without local anaesthetic. One week after infiltration, patients started a standardised sub--maximal eccentric reeducation.