orthobiology
Healing with the body's own growth factors (PRP)

A systematic review published by Meheux et al. [1] summarizes the results of randomized PRP studies with the highest level of evidence for symptomatic knee osteoarthritis. Six studies with a total of 739 patients, 817 knee joints and an average follow-up of 38 weeks were evaluated (min. 24, max. 52 weeks). In five studies, PRP was compared with HA, in one with placebo. The WOMAC (Western Ontario and McMaster Universities Osteoarthritis Index) and in one study the IKDC (International Knee Documentation Committee Subjective Knee Evaluation Form) score were used as the primary endpoint or clinical guideline score. In all six studies, a statistically significant and clinically relevant improvement in pain and joint function was found for PRP in the respective observation period compared to baseline. In four of the five comparative studies on PRP versus HA and in the study against placebo (saline solution), significantly better results were observed for PRP in the WOMAC score. Based on the study results to date, Meheux et al. see a possible use of PRP in symptomatic knee osteoarthritis, although this should not be greater than grade 3 in the radiological classification according to Kellgren and Lawrence (grades 1 to 3).

After a meta-analytic evaluation of 16 clinical studies with a total of 1,543 patients, another review by Chang et al. described better results for PRP for the symptomatic treatment of knee osteoarthritis compared to placebo or treatment with HA or a corticosteroid [2].

In addition, in three Level I studies according to the AHCPR (Agency for Healthcare Research and Quality), the clinical benefit and superiority of the PRP used here (ACP, Arthrex) over hyaluronic acid or placebo (saline solution) for gonarthrosis (up to grade 3) was explicitly demonstrated [3-5]. Patients were given 3-4 PRP injections at weekly intervals. The double-blind, randomized and FDA-controlled study by Dr. Smith is particularly noteworthy here. In this study, a significantly superior effectiveness (WOMAC score) over placebo was shown from the second week onwards for up to 12 months [3]. No side effects occurred either [3].
In summary, the current evidence suggests that PRP has a therapeutic value, particularly for mild to moderate osteoarthritis.

There are also a large number of studies for other indications that demonstrate the effectiveness of using the body's own plasma.

In a 2015 review by the authors Murray et al. [6], the evidence regarding PRP for the treatment of lateral epicondylitis was evaluated. A total of nine publications, including six randomized studies, were analyzed. The authors concluded that PRP injections lead to a long-lasting positive effect in the treatment of chronic lateral epicondylitis. The authors rated the effectiveness of PRP as superior to steroid injections at an evidence level II. In addition, the authors rated the application of PRP as superior to autologous whole blood injections and placebo/dry needling. After the review was published, two more randomized studies were conducted. The groups led by Yadav et al. [7] and Lebiedzinski et al. [8] from 2015 compared the effectiveness of PRP with a corticosteroid and concluded that PRP treatment is superior to corticosteroid treatment, particularly with regard to long-term effects. The randomized study by Varshney et al [9] from 2017 also compared the effectiveness of PRP with a corticosteroid. The authors concluded that treating epicondylitis with PRP leads to a reduction in pain and improvement in function that is superior to treatment with corticosteroids and consider PRP therapy to be the primary method in the treatment of chronic tendinopathies. In a retrospective comparison with a surgical procedure for lateral epicondylitis, Ford et al [10] came to the conclusion that both procedures lead to a comparable result, and that conservative treatment with PRP is therefore a good alternative to surgical treatment due to the significantly lower risks.

In the meta-analysis published in the AJSM in 2018, Andriolo et al. set themselves the goal of identifying the best conservative treatment option for patellar tendonitis based on the existing evidence [11]. The authors evaluated 70 studies, including 29 randomized controlled trials.