title: Are multiple platelet-rich plasma injections useful for treatment of chronic patellar tendinopathy in athletes? a prospective study.
abstract: BACKGROUND
  Chronic patellar tendinopathy (PT) is one of the most common overuse knee disorders. Platelet-rich plasma (PRP) appears to be a reliable nonoperative therapy for chronic PT.
  
  
  OBJECTIVE
  To evaluate clinical and radiological outcomes of 3 consecutive ultrasound (US)-guided PRP injections for the treatment of chronic PT in athletes.
  
  
  METHODS
  Case series; Level of evidence, 4.
  
  
  METHODS
  A total of 28 athletes (17 professional, 11 semiprofessional) with chronic PT refractory to nonoperative management were prospectively included for US-guided pure PRP injections into the site of the tendinopathy. The same treating physician at a single institution performed 3 consecutive injections 1 week apart, with the same PRP preparation used. All patients underwent clinical evaluation, including the Victorian Institute of Sport Assessment-Patella (VISA-P) score, visual analog scales (VAS) for pain, and Lysholm knee scale before surgery and after return to practice sports. Tendon healing was assessed with MRI at 1 and 3 months after the procedure.
  
  
  RESULTS
  The VISA-P, VAS, and Lysholm scores all significantly improved at the 2-year follow-up. The average preprocedure VISA-P, VAS, and Lysholm scores improved from 39 to 94 (P < .001), 7 to 0.8 (P < .0001), and 60 to 96 (P < .001), respectively, at the 2-year follow-up. Twenty-one of the 28 athletes returned to their presymptom sporting level at 3 months (range, 2-6 months) after the procedure. Follow-up MRI assessment showed improved structural integrity of the tendon at 3 months after the procedure and complete return to normal structural integrity of the tendon in 16 patients (57%). Seven patients did not recover their presymptom sporting level (among them, 6 were considered treatment failures): 3 patients returned to sport at a lesser level, 1 patient changed his sport activity (for other reasons), and 3 needed surgical intervention.
  
  
  CONCLUSIONS
  In this study, application of 3 consecutive US-guided PRP injections significantly improved symptoms and function in athletes with chronic PT and allowed fast recovery to their presymptom sporting level. The PRP treatment permitted a return to a normal architecture of the tendon as assessed by MRI.
authors: Christophe Charousset, Institut Osteo Articulaire Paris Courcelles-60 Rue de Courcelles, 75008 Paris, France. dr.charousset@ioapc.fr.
authors: Christophe
authors: C
authors: Charousset
authors: Amine
authors: A
authors: Zaoui
authors: Laurence
authors: L
authors: Bellaiche
authors: Benjamin
authors: B
authors: Bouyer
mesh_terms: D000293:Adolescent; D000328:Adult; D056352:Athletes; D002908:Chronic Disease; D005260:Female; D006801:Humans; D007267:Injections; D008279:Magnetic Resonance Imaging; D008297:Male; D010147:Pain Measurement; D017847:Patellar Ligament / Q000293:injuries*; D017713:Platelet Transfusion / Q000379:methods*; D053657:Platelet-Rich Plasma; D011446:Prospective Studies; D052256:Tendinopathy / Q000628:therapy*; D016896:Treatment Outcome; D018084:Ultrasonography, Interventional; D014945:Wound Healing / Q000502:physiology
keywords: jumper’s knee; patellar tendinopathy; platelet-rich plasma; treatment