Platelet-rich plasma (PRP) is a relatively new but quite promising technology in the field of regenerative therapeutics. It encompasses using the patient’s own serum to improve and restore the functioning of a diseased region of the body. 1 Given the fact that platelets are a rich source of several growth factors, like platelet-derived growth factor (PDGF), vascular endothelial growth factor (VEGF), transforming growth factor-beta (TGF-b), connective tissue growth factor, epidermal growth factor, and fibroblast growth factor (FGF) to name a few, it can be effectively used to promote the health of the diseased parts by virtue of its regenerative capacity. The technique makes use of and mimics the body’s natural response to an injurious event. Any laceration or indentation on the surface of the body, for instance, causes the platelets to migrate to the site of the event, where they form a temporary clot. The platelets then release chemotactic factors that promote angiogenesis, mitogenesis, macrophage activation, and cell proliferation, regeneration, modeling, and differentiation.
In the PRP technique, blood is centrifuged to form platelet-rich plasma, which can then be used for healing tissue injures, restoring the functioning of a diseased part, and for cosmetic purposes.
How does PRP work?
The process of PRP therapy is fairly straightforward. It starts with phlebotomy for taking the patient’s blood, which is then centrifuged to concentrate the platelets in the plasma. It is then introduced in the body exogenously either directly by injection or in the form of gel or any biomaterial. The different companies have different protocols for preparing and applying PRP. Depending on the type of problem and desired results, PRP is injected periodically into the affected region. The effects are observable over weeks to months. The outcome of PRP lasts much longer, and no serious side effects have been noticed thus far.
The introduction of PRP kits has further made the process hassle-free, allowing the physicians to avoid the centrifugation process. After thoroughly understanding the procedure, these kits can be easily used by doctors for therapeutic purposes.
The therapeutic effects of PRP:
PRP, first introduced by researchers to be used in oral surgery as an adjunct for bone graft, has now been implemented in many fields because of its potent healing properties. 1,2 It augments and restores the functioning of many different kinds of tissues. Musculoskeletal injury, particularly, often compromises the blood flow to the injured areas. Availability of various vascular and cell growth factors at these sites provides a promising healing result. 2
Why is PRP a better option than steroids?
Steroids are used extensively in medical settings because of their potent role in providing immediate symptomatic relief. They work by suppressing immunity and thus decreasing inflammation – the mechanism driving the pathological changes associated with a disease. The efficacy of steroids is well proven in many emergency conditions too. Where, on the one hand, they are an effective mode of treating critical conditions, the disastrous effects associated with their long-term use are well documented.
While they work by reducing the inflammatory activities in the affected region and halting the ongoing damage to the healthy tissue, they do not have any role in reversing or healing the damaged tissue. Thus, the effect is limited to time, and once it subsides, the inflammation returns. Consequently, the patient eventually becomes dependent on steroids for the long term.
PRP, on the other hand, is a biologically derived product from the patient’s own blood. When applied to the diseased site, it releases a number of growth factors and sets a cascade of healing events in motion. These substances enhance the natural healing ability of the body as well as reduce inflammation and alleviate symptoms, providing long-term relief. Since the inflamed tissue is already extremely vulnerable to infections, steroids being immunosuppressants are clearly not an ideal choice. Some studies suggest that PRP possesses antimicrobial activity as well and thus acts as a barrier against superimposed infections. 9
Epidural/spinal injections of PRP:
Chronic back pain is one of the most common complaints in adults. 3 The reasons behind it are numerous, ranging from simple muscle spasms to complex disc changes. The treatment of back pain is usually in the form of non-steroidal anti-inflammatory (NSAIDs) drugs and muscle relaxants. Some complex pathologies, however, are not cured easily and require more potent drugs such as steroids for symptomatic relief. Studies show that steroidal epidural injection is the most common mode of treatment for back pain. 4,5 The efficacy of steroidal spinal injections for symptomatic pain relief is well proven, but they do not affect the functional ability or decrease the surgery rate. Instead, the long-term therapeutic use of high-dose steroids may produce potential adverse effects. The steroids disrupt the endocrine, musculoskeletal, metabolic, cardiovascular, dermatologic, gastrointestinal, and nervous systems. Studies have shown that frequent application of steroidal injections increases the risk of fractures and contributes to significant bone loss, amplifying the destruction and thus, ultimately, increasing the pain. The steroids also alter the Hypothalamic-Pituitary-Adrenal axis, which eventually disturbs the normal physiology of the body.
Considering the negative health effects of the prolonged steroid use, it is important to have an alternative non-surgical option with a better safety profile. The role of regenerative medicine in this regard is remarkable. Regenerative medicine focuses on replacing, regenerating, and mitigating tissue catabolism. PRP, a form of regenerative therapy, is proven to be highly effective for the non-surgical management of chronic back pain. 6 PRP is already quite popular in orthopedics for curing tendinopathies, osteoarthritis, and sports injuries. 1 The promising results of PRP have also been obtained in the treatment of peripheral neuropathies and, even, nerve regeneration in some cases. The successful management of these has encouraged the researchers to use it in the treatment of radiculopathies, spinal facet syndrome, and intervertebral disc pathologies. 7
The PRP is gaining popularity because of its ability to restore the functioning of the diseased tissue. While the steroids act as a pain reliever, the PRP simultaneously heals the damaged tissue, alleviates the pain, and regenerates and modifies the cells allowing for better functioning. 8 Considering its anti-inflammatory, reparatory, and healing effects, PRP can serve as a substitute to conventional epidural/spinal steroidal injections. 7
PRP for spinal tissue injury:
Tissue injury can be acute or chronic. An acute injury is often a result of a sudden traumatic event resulting in a strain, sprain, or tear in a muscle or ligament. Chronic injuries are usually caused by repetitive stress or are a result of degenerative changes. The resulting inflammation, in either case, produces muscle pathologies, tendinopathies, and subsequently, chronic pain. Whatever the mechanism or mode of injury is, the primary response of the body is similar. The first event is hemostasis, followed by inflammation, cellular proliferation, and remodeling or tissue modification.
PRP consist of large amounts of platelets that promote rapid tissue healing. The various growth factors and cytokines present in platelets allow them to be one of the most effective responders to tissue injury. Allowing the numerous platelets to enter the damaged area, where they may not be able to reach naturally in many cases, produces desired effects rapidly. The growth factors in platelets correspond to all the phases of the body’s primary response. The platelets form the initial clog acting as a hemostat. The VEGF promotes angiogenesis, allowing the appropriate inflammation to occur in the desired way. TGF-b and FGF cover the inflammatory destruction by promoting cellular proliferation. The other growth factors then allow rapid modification and thus rapid recovery and restoration of the function. 1,10
PRP injections for specific spinal pathologies:
Spinal pathologies usually manifest in the form of back pain radiating to the peripheries, sensory and motor loss. All these eventually affect the quality of life and increase the morbidity rate. Studies have supported the use of PRP in the treatment of back pain. The efficacy and safety of PRP as a biological therapy for degenerative spinal conditions are also proven. A study evaluated the effectiveness of PRP in selected participants after confirming disc disease by using magnetic resonance imaging (MRI) and standardized provocative discography. The candidates were given PRP treatment and followed up for ten months. The results showed significant pain improvement without any obvious side effects. 11
PRP stimulates the injured area and starts the processes of proliferation, recruitment, and differentiation, initiating reparation. Subsequent release of growth factors like VEGF, EGF, TGF-b, and PDGF contributes to improving the integrity of the damaged tissue. The formation of cellular and extracellular matrix supports the destructing intervertebral disc, and thus, mitigates the disease severity. 12
One of the mechanisms of excessive tissue destruction is uncontrolled activation of the inflammatory cascade and an imbalance between inflammatory and counter hormones. The chemokines and cytokines within the platelets stimulate the immunological and inflammatory aspects of healing, while the anti-inflammatory cytokines counter the excessive recruitment of leukocytes. The smooth regulation of chemokines prevents excessive inflammation, increasing the healing and decreasing the damage.
Disc degeneration is a complex process. It can be due to aging, vascular insufficiency, apoptosis, diminished nutrients to the disc cells, and genetic factors. The avascular nature of the disc interferes with the healing of the tissue. Further, the inflammation-mediated changes occur in both nucleus pulposus and inner annulus fibrosus. This causes the disc cells to release a large number of pro-inflammatory cytokines amplifying the destruction. Injection of PRP directly into the affected disc allows the healing to occur smoothly. 12
- Redler, L. H., Thompson, S. A., Hsu, S. H., Ahmad, C. S., & Levine, W. N. (2011). Platelet-rich plasma therapy: a systematic literature review and evidence for clinical use. The Physician and sports medicine, 39(1), 42–51.
- Zhang, J. Y., Fabricant, P. D., Ishmael, C. R., Wang, J. C., Petrigliano, F. A., & Jones, K. J. (2016). Utilization of Platelet-Rich Plasma for Musculoskeletal Injuries: An Analysis of Current Treatment Trends in the United States. Orthopedic journal of sports medicine, 4(12), 2325967116676241.
- Meucci, R. D., Fassa, A. G., & Faria, N. M. (2015). Prevalence of chronic low back pain: systematic review. Revista de saude publica, 49, 1.
- Centeno, C., Markle, J., Dodson, E., Stemper, I., Hyzy, M., Williams, C., & Freeman, M. (2017). The use of lumbar epidural injection of platelet lysate for treatment of radicular pain. Journal of experimental orthopedics, 4(1), 38.
- Choi, H. J., Hahn, S., Kim, C. H., Jang, B. H., Park, S., Lee, S. M., Park, J. Y., Chung, C. K., & Park, B. J. (2013). Epidural steroid injection therapy for low back pain: a meta-analysis. International journal of technology assessment in health care, 29(3), 244–253.
- Samadi, P., Sheykhhasan, M., & Khoshinani, H. M. (2019). The Use of Platelet-Rich Plasma in Aesthetic and Regenerative Medicine: A Comprehensive Review. Aesthetic plastic surgery, 43(3), 803–814.
- Akeda, K., Yamada, J., Linn, E. T., Sudo, A., & Masuda, K. (2019). Platelet-rich plasma in the management of chronic low back pain: a critical review. Journal of pain research, 12, 753–767.
- Gupta, P. K., Acharya, A., Khanna, V., Roy, S., Khillan, K., & Sambandam, S. N. (2020). PRP versus steroids in a deadlock for efficacy: long-term stability versus short-term intensity-results from a randomised trial. Musculoskeletal surgery, 104(3), 285–294.
- Yang, L. C., Hu, S. W., Yan, M., Yang, J. J., Tsou, S. H., & Lin, Y. Y. (2015). Antimicrobial activity of platelet-rich plasma and other plasma preparations against periodontal pathogens. Journal of periodontology, 86(2), 310–318.
- Zhang, J. Y., Fabricant, P. D., Ishmael, C. R., Wang, J. C., Petrigliano, F. A., & Jones, K. J. (2016). Utilization of Platelet-Rich Plasma for Musculoskeletal Injuries: An Analysis of Current Treatment Trends in the United States. Orthopaedic journal of sports medicine, 4(12), 2325967116676241.
- Akeda, K., Ohishi, K., Masuda, K., Bae, W. C., Takegami, N., Yamada, J., Nakamura, T., Sakakibara, T., Kasai, Y., & Sudo, A. (2017). Intradiscal Injection of Autologous Platelet-Rich Plasma Releasate to Treat Discogenic Low Back Pain: A Preliminary Clinical Trial. Asian spine journal, 11(3), 380–389.
- Mohammed, S., & Yu, J. (2018). Platelet-rich plasma injections: an emerging therapy for chronic discogenic low back pain. Journal of spine surgery (Hong Kong), 4(1), 115–122.