Introduction

Tennis elbow (lateral epicondylitis) is a musculoskeletal disorder caused by repetitive overuse of the tendons that leads to pain and tenderness in the elbow. It is common among athletes, manual labourers, and those who engage in repetitive wrist extension and gripping activities.¹ Over time, individuals develop chronic pain, a reduction in their grip strength, and eventual functional impairment. This leads to a significant impact on professional performance as well as daily activities.

Current treatment challenges

Treatment for tennis elbow involves using nonsteroidal anti-inflammatory drugs (NSAIDs) and corticosteroid injections, which can provide short-term pain relief. Still, it can be associated with tendon degeneration and the recurrence of symptoms.² Similarly, while physiotherapy is the go-to in conservative management, it often requires long treatment durations, which can have variable and sometimes unfavourable outcomes.³ In severe cases, surgery is indicated where other interventions fail to help.

Tendon healing and the rise of regenerative medicine

Over the past 20 years, significant attention has been given to regenerative medicine's benefits in treating conditions such as tennis elbow. Platelet-Rich Plasma (PRP) therapy is being acknowledged as a promising alternative to traditional treatments.

PRP is a product derived from blood containing a high concentration of platelets. These cells work by releasing growth factors that support tendon healing, the production of collagen, and angiogenesis (the formation of new blood vessels).⁴ While corticosteroids suppress inflammation, PRP enhances the regeneration of damaged tissues, offering individuals a therapy that can have longer-lasting effects.

The following article will explore the efficacy and mechanisms of PRP for the treatment of tennis elbow as well as its limitations and future direction.

Understanding PRP therapy

What is Platelet-Rich Plasma (PRP)?

PRP is a blood product containing high concentrations of platelets suspended in plasma. It is produced using the patient’s blood, which is centrifuged. During this process, force separates red blood cells, white blood cells, and platelets (the latter are then suspended in the patient’s plasma). PRP therapy aims to utilise the regenerative properties of platelets, particularly their ability to release growth factors and cytokines, which are critical for tissue healing and repair.¹

Tendon healing and the biological mechanism of PRP

The high concentration of bioactive molecules in PRP causes the regeneration of tissues at the site of injury via various biological mechanisms. There is a significant increase in collagen synthesis at the treatment site, which is essential for the flexibility and strengthening of tendons.² 

The presence of growth factors, particularly vascular endothelial growth factor, regenerates blood supply by promoting angiogenesis (the formation of new blood vessels).³ PRP also contains other growth factors that reduce inflammation, promote tissue repair and regeneration.^4,5

The two types of PRP therapies and their clinical implications

There are two types of PRP therapy: 

• Leukocyte-Rich PRP (LR-PRP): LR-PRP contains a high concentration of white blood cells together with platelets, which proposes to utilise the body’s natural inflammatory response, thereby making it more suitable for individuals suffering from chronic pain⁷ 
• Leukocyte-Poor PRP (LP-PRP): LP-PRP contains lower concentrations of white blood cells, which reduces the inflammatory response while promoting tendon healing, and is more suitable for individuals with severe tendon degeneration or low pain tolerance⁸

PRP injection procedure

The process begins with preparing the injection, whereby a 15-30ml blood sample is taken from the patient and centrifuged to separate the platelets from other blood components.The patient is then injected using either blind injection or ultrasound. The former relies on the practitioner’s experience to inject into the anatomically correct area. However, this leads to a higher variability in results due to inconsistency in targeting the affected tendon during each session.¹¹ 

Alternatively, using ultrasound to guide the practitioner to the site for treatment has been shown to lead to better clinical outcomes due to the precision and distribution of the injection at the site of injury.⁹ In fact, a 2024 clinical study found that ultrasound-guided PRP resulted in better pain relief, tendon healing and overall clinical outcomes.¹²

Optimal PRP treatment protocols

PRP therapy for tennis elbow usually involves 1 to 3 injections every 2-4 weeks. This is generally followed by a post-injection rehabilitation regimen, which includes reducing strain on the affected elbow, eccentric exercises to improve tendon regeneration, and physical therapy to improve strength over time.¹⁰

PRP vs. traditional treatments

Tennis elbow is traditionally treated using non-invasive and invasive treatments to reduce symptomatic pain. PRP has emerged as an alternative that aims to deliver a biological alternative that promotes healing while reducing chronic pain.

PRP vs. corticosteroid injections

Corticosteroid injections are widely used to treat tennis elbow because they reduce inflammation and provide immediate pain relief. However, various studies have reported tendon degeneration due to suppression of collagen synthesis.¹ Although corticosteroids were more effective than PRP in pain reduction after a month, at the 6-month mark, PRP provided a superior pain reduction, lower recurrence rate and improved grip strength.^2,3

PRP vs. physiotherapy

While physiotherapy is still regarded as a cornerstone of tennis elbow treatment, improving tendon strength and elasticity while stimulating collagen remodelling, several studies have concluded that the addition of PRP treatment together with physiotherapy improves the overall outcome and long-term results for both treatments, compared to physiotherapy alone.^4,5,6

PRP vs. shockwave therapy (ESWT)

Shockwave therapy (ESWT) is another treatment option that claims to promote healing by causing microtrauma in the site of injury. This causes an increase in blood flow, stimulating angiogenesis and the production of collagen.⁷ However, a 2023 study found that although ESWT reduces pain, it does not have a significant effect on the structure of the tendon, while PRP improves both structural integrity and pain reduction.^8,9

PRP vs. autologous blood injections (ABI)

Similarly to PRP, autologous blood injection (ABI) is extracted from the patient, however, it does not undergo centrifugation. The sample is injected whole, containing all the components of the patient’s blood. The mechanism relies on the body’s natural platelet activation to promote healing. However, a 2024 study found that patients who underwent PRP experienced faster pain relief, recovery and significantly improved the functionality of the tendon than those undergoing ABI.^10,11

Limitations and challenges of PRP therapy

Despite the growing popularity of PRP therapy for the treatment of tennis elbow, it is not without limitations that the clinical outcomes of the treatment are affected.

Variability in PRP preparation and composition

One of the biggest challenges in PRP therapy is maintaining the same preparation protocols throughout the treatment. A 2025 study found that variability in centrifugation techniques, platelet concentrations, and leukocyte content led to inconsistent clinical results.^1,2

Cost

PRP therapy is often expensive. A single injection can cost between £200 to £600, depending on the practitioner. While corticosteroid injections are more cost-effective per treatment, there is a higher recurrence rate. Therefore, PRP injections, while having a higher upfront cost, will provide longer-lasting pain relief and can reduce the likelihood of surgery.⁴

Patient-specific factors and their effect on PRP therapy success

Older patients may have a lower platelet function, which reduces the success of PRP treatment. Studies have shown that younger patients who are more active respond better to PRP than elderly patients.⁵ Additionally, people with the VEGFA gene variant have faster pain relief with PRP therapy.⁶ Therefore, there is a potential for personalised PRP treatments based on genetic profiling, which may enhance the success of PRP.

Concerns over regulation

Regulation for PRP differs across the world, and in many countries, PRP is not classified as a drug, but rather a minimally manipulated autologous therapy. In the UK and EU, PRP still lacks standardised medical guidelines, while the FDA in the USA has not approved its use for tennis elbow. This means that clinicians are performing the treatment off-label.⁸ Therefore, establishing international guidelines for PRP preparation, dosing and application will improve treatment reliability while carrying regulatory approval.

Future directions in PRP therapy

While PRP therapy is gaining traction as the main treatment for tennis elbow, research focuses on optimising formulations, enhancing injection precision, and integrating new biotechnologies.

Optimisation of PRP formulations

PTP preparation can be variable in its constituents, with higher platelet concentrations showing better pain relief and tendon healing. In contrast, low concentrations may benefit those who suffer from the chronic form of the condition.^1,2 Additionally, Leukocyte-rich PRP benefits chronic cases but may exacerbate pain. At the same time, Leukocyte-poor PRP reduces pain but may not have as much of a long-term effect on tendon healing.^3,4 Therefore, it may be the case that PRP should be a tailored treatment based on the severity of pain and the chronicity of the condition.

AI and PRP therapy

Artificial intelligence (AI) is being explored as a means to predict PRP success rates and customise treatment plans for patients with tennis elbow. AI-driven models could be used to scan and analyse patient demographics, identify genetic markers, and map the platelet profile of a patient. This could mean a more enhanced PRP treatment, focused on precision and efficiency, powered by AI-decision making.

Summary

PRP is fast growing as the leading treatment for tennis elbow, with strong clinical evidence supporting the long-term outcomes of the therapy. It provides a superior tendon healing capacity with fewer recurrence rates when compared to conventional treatments such as corticosteroids, physiotherapy and shockwave therapy. 

Various challenges remain, such as variability in the treatment formulations, cost and regulatory inconsistencies, but the future is bright. AI-driven decision-making could revolutionise PRP therapy, improving patient selection and treatment outcomes. With continued improvements, PRP is fast becoming the standard for precision-based therapies for tennis elbow.