title: Platelet-rich plasma vs hyaluronic acid to treat knee degenerative pathology: study design and preliminary results of a randomized controlled trial.
abstract: BACKGROUND
  Platelet rich plasma (PRP), a blood-derived product rich in growth factors, is a promising treatment for cartilage defects but there is still a lack of clinical evidence. The aim of this study is to show, through a randomized double blind prospective trial, the efficacy of this procedure, by comparing PRP to Hyaluronic Acid (HA) injections for the treatment of knee chondropathy or osteoarthritis (OA).
  
  
  METHODS
  109 patients (55 treated with HA and 54 with PRP) were treated and evaluated at 12 months of follow-up. The patients were enrolled according to the following inclusion criteria: age > 18 years, history of chronic (at least 4 months) pain or swelling of the knee and imaging findings of degenerative changes of the joint (Kellgren-Lawrence Score up to 3). A cycle of 3 weekly injections was administered blindly. All patients were prospectively evaluated before and at 2, 6, and 12 months after the treatment by: IKDC, EQ-VAS, TEGNER, and KOOS scores. Range of motion and knee circumference changes were measured over time. Adverse events and patient satisfaction were also recorded.
  
  
  RESULTS
  Only minor adverse events were detected in some patients, such as mild pain and effusion after the injections, in particular in the PRP group, where a significantly higher post-injective pain reaction was observed (p=0.039). At the follow-up evaluations, both groups presented a clinical improvement but the comparison between the two groups showed a not statistically significant difference in all scores evaluated. A trend favorable for the PRP group was only found in patients with low grade articular degeneration (Kellgren-Lawrence score up to 2).
  
  
  CONCLUSIONS
  Results suggest that PRP injections offer a significant clinical improvement up to one year of follow-up. However, conversely to what was shown by the current literature, for middle-aged patients with moderate signs of OA, PRP results were not better than those obtained with HA injections, and thus it should not be considered as first line treatment. More promising results are shown for its use in low grade degeneration, but they still have to be confirmed.
authors.affiliation: Nano-Biotechnology Laboratory, Rizzoli Orthopaedic Institute, Via di Barbiano n. 1/10, Bologna 40136, Italy.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Filardo
authors.forename: Elizaveta
authors.initials: E
authors.lastname: Kon
authors.forename: Alessandro
authors.initials: A
authors.lastname: Di Martino
authors.forename: Berardo
authors.initials: B
authors.lastname: Di Matteo
authors.forename: Maria Letizia
authors.initials: ML
authors.lastname: Merli
authors.forename: Annarita
authors.initials: A
authors.lastname: Cenacchi
authors.forename: Pier Maria
authors.initials: PM
authors.lastname: Fornasari
authors.forename: Maurilio
authors.initials: M
authors.lastname: Marcacci
mesh_terms: D000704:Analysis of Variance; D001696:Biomechanical Phenomena; D002357:Cartilage Diseases / Q000175:diagnosis / Q000473:pathology / Q000503:physiopathology / Q000628:therapy*; D016009:Chi-Square Distribution; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D006820:Hyaluronic Acid / Q000008:administration & dosage*; D007270:Injections, Intra-Articular; D007558:Italy; D007719:Knee Joint / Q000187:drug effects* / Q000473:pathology / Q000503:physiopathology; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000175:diagnosis / Q000473:pathology / Q000503:physiopathology / Q000628:therapy*; D017060:Patient Satisfaction; D053657:Platelet-Rich Plasma; D011446:Prospective Studies; D016059:Range of Motion, Articular; D020127:Recovery of Function; D013997:Time Factors; D016896:Treatment Outcome; D055676:Viscosupplementation; D055675:Viscosupplements / Q000008:administration & dosage*
chemical_list: D055675:Viscosupplements; D006820:Hyaluronic Acid