Four Injection Therapies for Tennis Elbow – A Review

Tennis elbow, or lateral epicondylitis, is a tendon disorder that can affect athletes and workers with pain and disability that can last for years. It has traditionally been thought to be caused by inflammation of the tendons. Existing therapies such as rest, exercise, NSAIDs, and cortisone injections don’t always relieve pain or improve function.  In the long term, cortisone injections may even make the condition worse, or harder to recover.  (Link)

Current evidence suggests that the tendon pathology is actually degenerative change rather than inflammation.  Abnormal blood vessels become present in the tendon and collagen fibers become disorganized. Four injection therapies – Prolotherapy, platelet-rich plasma, whole blood, and polidocanol have been used to target the tendon pathology and are showing promise as effective therapies. Researchers at the University of Wisconsin conducted a systemic review of these injection therapies on tennis elbow.

injection therapies

The Study Method

  • Prospective controlled studies of human clinical trials that involved pre and post assessments were identified. Study designs were assessed for internal validity and each study received a quality score.
  • For the nine studies that met criteria, the effect size of outcomes was calculated so that studies could be compared.
  • Four controlled studies and five prospective case series were included. Three evaluated prolotherapy, two evaluated Polidocanol, three evaluated autologous whole blood, and one evaluated PRP for a total of 208 adult subjects who had failed conservative therapy. Ultrasound confirmed subjects had neovascularisation and structural changes in the tendon.


  • All the injection therapies showed promising results with large effect sizes and no side effects however sample sizes were small so results must be interpreted cautiously.


  • Prolotherapy subjects reported 90% improvement at 16 weeks.


  • Polidocanol decreased pain by 55% and increased grip strength at 8 months. Ultrasound showed improved structural defects and vascularity.


  • Studies using whole blood reported significant improvement in the range of 64% to 88%.


  • A single injection of PRP resulted in 81% improvement at 27 weeks and 93% at 25.6 months.


Why Do Regenerative Injection Therapies Work?

  • Injection therapy places the intervention directly at the degenerative site. It is thought to stimulate regenerative cofactors.
  • Prolotherapy contains hyperosmolar dextrose and this component has been shown to increase platelet-derived growth factor which may act as a signaling factor in tendon repair.
  • PRP is rich in growth factors and has bioactive signaling factors for tendon repair.

In conclusion, all four injection therapies are treatment options for hard to heal lateral epicondyle tendinopathy (tennis elbow) patients and are safe when performed by a skilled clinician.  However, Prolotherapy and PRP treatments are more common and have more research available.  

Rabago, D, Best, TM, Zgierska, A, Zeisig, E, Ryan, M. & Crane, D. (2009).

A systemic review of four injection therapies for lateral epicondylosis: prolotherapy, polidocanol, whole blood and platelet-rich plasma. British J of Sports Medicine, 443: 471-481.


Four Injection Therapies for Tennis Elbow – A Review

Tennis elbow, or lateral epicondylitis, is a tendon disorder that can affect athletes and workers with pain and disability that can last for years. It has traditionally been thought to be caused by inflammation of the tendons. Existing therapies such as rest, exercise, NSAIDs, and cortisone injections don’t always relieve …

Pain Management Injection Therapies for Low Back Pain

Pain Management Injection Therapies for Low Back Pain [Internet]. Chou R(1), Hashimoto R(1), Friedly J(1), Fu R(1), Dana T(1), Sullivan S(1), Bougatsos C(1), Jarvik J(1). Rockville (MD): Agency for Healthcare Research and Quality (US); 2015. AHRQ Technology Assessments. Author information: (1)Pacific Northwest  …


systematic review studying various injection therapies found that prolotherapy and hyaluronic acid injection therapies were more effective than placebo

Stem cell secretome

transdifferentiation is the primary mechanism of effect of stem cell injection therapies. The most commonly used type of stem cells for therapeutic use are


Can Cortisone Injections Make Tennis Elbow Worse?

cortisone injections


Corticosteroid injections were introduced in the 1940s and they soon became popular in the treatment of sports-related injuries because they provide prompt pain relief. When clinical trials were introduced in the 1950s they shed doubt on the long-term effect of cortisone injections. While patients enjoyed the dramatic short-term relief of pain, the injury often relapsed within six months. However, these findings did not dampen enthusiasm for cortisone injections since too many people they seemed a better alternative to rest and physical therapy. However, a major review article published in The Lancet in 2010 intensifies the doubts about the efficacy of cortisone injections.


The Study Method

  • The Lancet study was a meta-analysis, a scientific way of pooling data from many small studies to increase the study size making the findings more powerful than individual small studies.
  • Forty-one high-quality randomized controlled clinical trials were pooled, creating a database of 2672 subjects.


  • Compared to other interventions, cortisone injections reduced tennis elbow pain in the short-term, but this effect was reversed at 6 and 12 months. There was a 63% risk of relapse and lower recovery rate compared to those who did not receive cortisone injections.


  • In contrast, hyaluronate injections reduced pain in the short term as well as at 6 and 12 months and Prolotherapy provided confirmed relief at 6 months.


  • People receiving multiple steroid injections are especially at high risk for worsening damage. An average of 4 injections results in a 57% worse outcome when compared to one injection.


  • The authors conclude that for tennis elbow, cortisone injections seem counterproductive.


Why is this study important?

Cortisone injections have become a standard of practice and are frequently requested by patients because they do provide rapid relief of pain. However, patients, particular athletes, should consider the long-term effects of cortisone injections as they may decrease the tendons regenerative potential.

  • For many years it was believed that tendon over-use injuries were caused by inflammation. It was logical to use cortisone as a treatment because it is an anti-inflammatory medication.  However, numerous studies now show convincingly that chemical markers of inflammation cannot be found in these overuse injuries. We now know that fibers within the tendons fray, which indicates the injury is due to degeneration.
  • It must be asked, ‘Why do cortisone injections appear to work in the short term?’ The answer is they seem to have an effect on the neural receptors that produce the pain signal. However, they have not been shown to heal structural defects, instead, they may actually impede tissue healing.
  • While there will always be a desire for a “quick fix,” the author of the Lancet study advises that athletes with tennis elbow think carefully about the wisdom of cortisone shots.  New, emerging cellular treatments, such as platelet-rich plasma (PRP), show great promise in healing tendon pain and injury.



Coombs, B., Bisset, L. & Vicenzino, B. (2010). Efficacy and safety of corticosteroid injections and other injections for management of tendinopathy: A systematic review of randomized controlled trials. The Lancet. 376(9754):1751-1767.

Reynolds, G. (2010). Phys Ed: Do cortisone shots actually make things worse?