Choice of intra-articular injection in treatment of knee osteoarthritis: platelet-rich plasma, hyaluronic acid or ozone options

Knee Surg Sports Traumatol Arthrosc. 2017 Feb;25(2):485-492. doi: 10.1007/s00167-016-4110-5. Epub 2016 Apr 7.


Purpose: This study was performed to compare the efficacy of treatment in three groups of patients with knee osteoarthritis (OA) given an intra-articular injection of platelet-rich plasma (PRP), hyaluronic acid (HA) or ozone gas.

Methods: A total of 102 patients with mild-moderate and moderate knee OA who presented at the polyclinic with at least a 1-year history of knee pain and VAS score ≥4 were randomly separated into three groups. Group 1 (PRP group) received intra-articular injection of PRP × 2 doses, Group 2 (HA group) received a single dose of HA, and Group 3 (Ozone group) received ozone × four doses. Weight-bearing anteroposterior-lateral and Merchant's radiographs of both knees were evaluated. WOMAC and VAS scores were applied to all patients on first presentation and at 1, 3, 6 and 12 months.

Results: At the end of the 1st month after injection, significant improvements were seen in all groups. In the 3rd month, the improvements in WOMAC and VAS scores were similar in Groups 1 and 2, while those in Group 3 were lower (p < 0.001). At the 6th month, while the clinical efficacies of PRP and HA were similar and continued, the clinical effect of ozone had disappeared (p < 0.001). At the end of the 12th month, PRP was determined to be both statistically and clinically superior to HA (p < 0.001).

Conclusion: In the treatment of mild-moderate knee OA, PRP was more successful than HA and ozone injections, as the application alone was sufficient to provide at least 12 months of pain-free daily living activities.

Level of evidence: Therapeutic study, Level I.

Keywords: Hyaluronic acid; Intra-articular injection options; Knee osteoarthritis; Ozone; Platelet-rich plasma.

Publication types

  • Randomized Controlled Trial

MeSH terms

  • Aged
  • Choice Behavior*
  • Female
  • Humans
  • Hyaluronic Acid / administration & dosage*
  • Injections, Intra-Articular*
  • Knee Joint / physiopathology
  • Male
  • Middle Aged
  • Osteoarthritis, Knee / drug therapy*
  • Ozone / administration & dosage*
  • Pain / drug therapy*
  • Pain Measurement
  • Platelet-Rich Plasma*
  • Radiography
  • Treatment Outcome
  • Weight-Bearing


  • Ozone
  • Hyaluronic Acid