Lateral epicondylitis, more commonly known as “tennis elbow,” is a common musculoskeletal disorder of the elbow that is characterized by lateral epicondylar pain and tenderness over the origin of the common extensor tendon of the forearm. It is typically exacerbated by resisted extension of the wrist, which activates the extensor muscles of the forearm and pulls on the common extensor tendon. The term “tennis elbow” was coined by H.P. Major in 1883 in relation to a publication by Mr. Henry Morris in The Lancet in 1882 describing the condition as “the lawn tennis arm” that resulted from frequent back stroke. However, the prevalence of the condition in tennis players is reported at 1.3% to 14.1%. Lateral epicondylitis is most often seen in the patient’s dominant arm. The patient will usually have point tenderness over the lateral epicondyle at the origin of the common extensor tendon. The condition is most commonly seen in manual labor intensive industries where repetitive “turn and screw” movements have been identified as a risk factor. Some synonyms for lateral epicondylitis include ECRB tendinopathy, lateral epicondylalgia and epicondylosis.


The extensor muscles of the forearm form the posterior compartment of the forearm and are responsible for extension of the wrist and fingers. The primary structure involved in lateral epicondylitis is the extensor carpi radialis brevis, or ECRB, tendon, which attaches to the lateral epicondyle of the humerus. The position of the ECRB tendon as it crosses the elbow joint makes it vulnerable to contact and abrasion against the lateral edge of the capitellum during elbow movement, especially extension and pronation of the forearm. It is improtant to remember that lateral epicondylitis is caused by chronic degenerative changes to the origin of the ECRB tendon and is NOT an acute inflammatory problem. Therefore, a more appropriate name for the condition would be “lateral epicondylopathy” (instead of “–itis”), indicating a chronic tendon degeneration rather than an acute inflammatory problem.

Natural History

The onset of lateral epicondylitis is usually incidious and occurs over a period of time, resulting from reptitive stress and overuse microtrauma to the ECRB tendon insertion. The condition is typically not caused by an acute traumatic event to the elbow.  The condition is characterized by three phases of progression: acute phase (within the first 3 months), subacute phase (3-6 months), and chronic phase (more than 6 months duration). A conservative management approach should be considered as a first line approach to an acute stage of lateral epicondylitis. The patient should begin by resting their elbow and icing it as much as possible, in conjunction with other conservative measures such as a non-steroidal anti-inflammatory (NSAID) medication and a daytime forearm brace placed over the ECRB tendon just distal to the lateral epicondyle. This conservative approach will alleviate the symptoms in approximately 90 to 95% of cases. However, with continuous repetitive trauma, microtears may propagate and can progress to macroscopic tears and to eventual rupture of the tendon or avulsion from the bony attachment. Chronic cases may evolve to include other surrounding tendons and can lead to weakened wrist extension and supination of the forearm in the setting of chronic elbow pain.

Physical Exam

Before performing a physical exam, one should take note of the patient’s history documenting when the pain started, the consistency of the pain, what activities aggravate the elbow, the patient’s occupation, and what treatment options have been employed up to this point. The physician may perform special tests such as Mill’s Test, Cozen’s Test, and the chair test to help diagnose lateral epicondylitis. Pain and tenderness to palpation just anterior and distal to the lateral epicondyle over the origin of the ECRB tendon is the classic clinical finding in lateral epicondylitis. Weak grip strength and resisted supination are also consistent with the diagnosis. The affected elbow should always be compared to the contralateral elbow as a point of reference when assessing strength and range of motion.

Imaging/ Diagnostics

  • X-Ray

  • MRI

  • Ultrasound

Differential Diagnosis

  • Posterolateral Elbow Plica Impingement: Causes a pain at the lateral epicondyle with a clicking sound.

  • Radial Tunnel Syndrome (RTS)

  • Posterolateral Rotatory Instability (PLRI)

  • Osteoarthritis

Nonoperative Treatment

More than 40 different treatment modalities have been studied for the management or lateral epicondylitis. It is important to remember that approximately 90 to 95% of cases can be managed with an appropriate course of conservative therapy.

Treatment modalities include:

  • Bracing

  • Local corticosteroid injection – this may provide short-term pain relief you to suppression of the local inflammation and an analgesic effect of the injection. However, local steroid injections have a higher recurrence rate of approximately 72% and me cause a negative effect on the tendon integrity over time which may worsen the symptomatology.

  • Platelet-rich Plasma (PRP) – PRP has become the mainstay of treatment for lateral epicondylitis over the last few years and has been studied extensively for the condition. The optimal PRP formulation and application regimen continues to evolve with more studies emerging. Various randomized controlled trials have been published that show consistent pain reduction and functional improvement that is preferred over corticosteroid.

  • Massage therapy

  • Extracorporeal Shockwave Therapy (ECST)

  • Prolotherapy

Surgical Treatment

In the event that symptoms do not improve over time with a nonoperative treartment approach, a patient may want to consider surgery. Three major surgical options have been described for the treatment of lateral epicondylitis. These are 1) open surgical techniques, 2) percutaneous release of the ECRB tendon, and 3) arthroscopic treatment.

The primary indication for surgical management of epicondylitis is a failure of a six-month course of adequate nonoperative treatment that has included some of the modalities mentioned above. Appropriate imaging and other diagnostic studies such as an ultrasound or MRI should be considered prior to proceeding with surgical intervention to rule out other important diagnoses.

Clinical Studies

Platelet rich plasma injections for lateral epicondylitis of the elbow reduce the need for surgical intervention. J Orthop. 2018.

Platelet-rich plasma for chronic lateral epicondylitis: is one injection sufficient? Arch Orthop Trauma Surg. 2015

Ongoing positive effect of platelet-rich plasma versus corticosteroid injection in lateral epicondylitis: a double-blind randomized controlled trial with 2-year follow-up. AJSM 2011.

The effect of platelet-rich plasma on clinical outcomes in lateral epicondylitis. Arthroscopy 2013.

Comparison of the Clinical Outcomes of Open Surgery Versus Arthroscopic Surgery for Chronic Refractory Lateral Epicondylitis of the Elbow. Orthopedics 2018.

The effect of corticosteroid versus platelet-rich plasma injection therapies for the management of lateral epicondylitis: A systematic review. SICOT J. 2018.

Treatment of lateral epicondylitis with platelet-rich plasma, glucocorticoid, or saline: a randomized, double-blind, placebo-controlled trial. AJSM 2013.

Surgical Treatment of Lateral Epicondylitis: A Prospective, Randomized, Double-Blinded, Placebo-Controlled Clinical Trial. AJSM 2018.

Ten- to 14-year follow-up of the Nirschl surgical technique for lateral epicondylitis. AJSM 2008.

Is eccentric exercise an effective treatment for lateral epicondylitis? A systematic review. Clin Rehabil. 2014.

Does effectiveness of exercise therapy and mobilisation techniques offer guidance for the treatment of lateral and medial epicondylitis? A systematic review. BJSM 2014.

A Comparison of Radiofrequency-Based Microtenotomy and Arthroscopic Release of the Extensor Carpi Radialis Brevis Tendon in Recalcitrant Lateral Epicondylitis: A Prospective Randomized Controlled Study. Arthroscopy 2018.

Autologous US-guided PRP injection versus US-guided focal extracorporeal shock wave therapy for chronic lateral epicondylitis: A minimum of 2-year follow-up retrospective comparative study. J Orthop Surg (Hong Kong). 2018.

Platelet-rich plasma versus autologous blood versus steroid injection in lateral epicondylitis: systematic review and network meta-analysis. J Orthop Traumatol. 2016.

Comparative effectiveness of injection therapies in lateral epicondylitis: a systematic review and network meta-analysis of randomized controlled trials. AJSM 2013.