Page 29 - 2020 ISAKOS Newsletter Volume I

PRP can be obtained from the patient on the same day as the injection is given and is processed through minimal steps, making it both cost-effective and convenient for treatment in patients with OA. To date, randomized controlled trials have demonstrated safety and superior efficacy of PRP than HA in knee osteoarthritis at 12 months.1,2 Better outcomes have been reported in younger patients or with mild to moderate OA without malalignment, smokers, or obesity. Initial research suggests that leukocyte-poor platelet-rich plasma (LP-PRP) may have stronger efficacy for intra-articular application. PRP has been shown to provide relief from pain and inflammation associated with OA, making it a viable treatment in the management of OA.1
Some new studies suggest that the combined application of PRP with HA could have a synergistic effect on treatment for OA.
Cell Based Therapies
Bone Marrow Aspirate Concentrate (BMAC)
Bone marrow aspirate concentrate is classified through the US Food and Drug Administration (FDA) as a 361 product and, hence, it is not subject to premarket review and approval. BMAC has progenitor cells and growth factors with reparative, homing, and trophic properties causing cellular migration to areas of damage. Numerous factors are released that can help in healing and inflammation modulation. BMAC has recently been shown to have an increased concentration of Interleuquin 1 Receptor Antagonist (IL-1RA), which, in combination with the other constituents, may provide anti- inflammatory and immunomodulatory effects. Few studies (underpowered) have demonstrated patient safety and improved clinical outcomes after BMAC treatment for OA; however, there is a paucity of high-level studies or randomized trials with joint osteoarthritis.
Adipose-derived Stromal Cell
Adipose-derived stromal cell therapy (ASC), also known as adipose stromal vascular fraction (SVF) therapy, has gained recent popularity as a treatment. Compared with BMAC, adipose tissue has been reported to have larger quantities of progenitor cells. Previous literature demonstrated significant reduction in Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), an improvement in Lysholm score, and significant pain reduction (VAS). Improvements in MRI scores were also reported. Although promising, these studies have been insufficient to conclude the efficacy of ASC therapy to adopt it into standard practices.
Amniotic Tissue
An emerging new allogenic orthobiologic option, amniotic tissue, has also been shown to be a source of bioactive components. Amnion, chorion, amniotic fluid, and the umbilical cord are distinct placental tissues that have been investigated. They are reported to contain growth factors, cytokines, and vasoactive peptides that modulate inflammation.
In addition, they contain amniotic epithelial cells and amniotic mononuclear undifferentiated stromal cells, which have chondrogenic and osteogenic differentiation capacity. Amnions (AM) are also a rich sources of hyaluronic acid and proteoglycans, which could play a role in the potential therapeutic relief of OA. Currently, there are several commercially available formulations of AM that differ based on content as well as how they were preserved. Current literature contains evidence that is insufficient to conclude the efficacy of this treatment.
Injections for Muscle Injuries
Platelet Rich Plasma (PRP) and Platelet Poor Plasma (PPP)
The increase of activation of satellite cells improving the muscle fiber’s diameter and the enhancement of the myogenesis are some of the mechanisms of PRP from fibroblast growth factor (FGF-2) and transforming growth factor- 1 (TGF- 1) to stimulate the healing response. There are conflicting reports in the literature. Some randomized controlled trials (RCTs) showed no difference for acute hamstring muscle injuries treated with PRP vs physical therapy on time to return to play and the re-injury rate. One RCT showed a shorter time to return to play in the PRP group compared to a control group with no injection but comparable re-injury rates. Another study using PRP under ultrasound guidance, in professional football players with hamstring injuries (grade 2 in MRI classification) demonstrated a smaller scar and excellent repair tissue with a mean follow- up of 36.6 months but no difference in return to play. New preclinical studies are showing better healing with less fibrotic tissue using a low concentration of platelet (less than 2X) platelet-poor plasma (PPP)3 or losartan that inhibits the effects of TGF- 1, a critical factor in the development of scar tissue. PRP could be an adjuvant therapy if we find the right preparation.
Injections for Tendon Injuries
Corticosteroids
When considering corticosteroid injections for tendinopathies, the risk of possible medium-term harm must be weighed up against any short-term efficacy.
Platelet Rich Plasma (PRP)
Rotator Cuff
Randomized Controlled Trials (RCTs) studies comparing PRP with placebo or corticosteroid injection demonstrated early improvement in pain relief and functional outcome scores for a period of 6-month follow-up. PRP injection was not more effective than placebo at 1-year follow-up, in pain, improving quality of life, disability, and shoulder range of motion in patients with chronic rotator cuff tears who were treated with an exercise program.
CURRENT CONCEPTS
ISAKOS NEWSLETTER 2020: VOLUME I 27