Common Extensor Tendinopathy

What is in a name?

Tennis elbow, lateral epicondylitis or (as it is now known) common extensor tendinopathy all refer to the most common lateral elbow pain presentation we see in patients. So why the many names?

Tennis elbow has been seen as an unsatisfactory term as it not only does not give any understanding of the pathophysiology underlying the condition but it is also more common in non-tennis players then tennis players.

Lateral epicondylitis suggests the main pathophysiology is inflammation on the epicondyle attachment when research suggests the primary pathology is disarray of the collagen of the extensor tendons with very little inflammation involved. Hence the preferred term for this pathology is common extensor tendinopathy.

Pathophysiology

Common extensor tendinopathy is an overuse injury due to excessive loading occurring from repeated wrist extension against resistance. This occurs in sports such as tennis and badminton as well as manual occupations such as bricklaying and carpentry as well as other hobbies such as sewing and knitting.

Tendons are made to withstand strong tensile loads but are not as tolerant of shear forces. As the Extensor Carpi Radialis Brevis crosses both the elbow and wrist, it undergoes considerable shear stress during wrist extension. This stress may be exacerbated by the force applied by the head of the radius as it rotates into pronation. Tendons respond to excessive stress by tissue deformation leading to collagen disarray and separation.

Although it is not known for sure whether acute inflammation precedes this disarray, animal models suggest inflammation is likely to last only briefly and tendon vascularity has been shown to be compromised in sites of friction, torsion or compression. Continued loading of the Extensor Carpi Radialis Brevis combined with its poor blood supply will lead to collagen disarray, separation and Tendinopathy.

Histology also shows a proliferation of nociceptors in this abnormal tissue. If the patient continues to overuse this tendon, they may also develop microscopic tears and scarring.

Clinical presentation

Patients are most likely to present with a gradual insidious onset of lateral elbow pain. This may be preceded by some unusual or increased activity (using a new racket, using a forklift with a new joystick, excessive data entry on the computer, increased gardening).

Patients may present with an acute onset but are most likely to describe a single instance of exertion of the wrist extensors such as lifting a large object. The patient may complain of difficulty lifting objects (coffee cup, milk from the fridge) or having a loss of gripping strength.

Objectively, the patient is likely to be painful over the lateral epicondyle and 1-2 cm distal. They will have pain on resisted wrist extension as well as extension of the 3rd finger. They
may also find gripping painful. Assessment of the cervical spine is also useful as there may be a neural component.

Treatment options

There is no one treatment option that appears to be entirely beneficial but rather a combination of treatments.

Medical treatments

Corticosteroid injection treatment is controversial for common extensor tendinopathy.

Although, unlike the Achilles tendon, there does not appear to be the cases of ruptures associated with corticosteroid injections into the common extensor origin, corticosteroid injections have only been found to be more effective than physiotherapy treatment in the short term, with physiotherapy treatment found to be more effective after 12 weeks.

Brukner and Kahn recommend the use of corticosteroid injections only after the failure of conservative treatment and even then, to be only considered one part of a combined treatment approach.

There is some evidence that the use of nitric oxide donor therapy (or GTN patches) applied at a dose of 0.25mg for 24 hours may be beneficial in improving pain and function.

Autologous blood injections are thought to potentially initiate an inflammatory cascade in the degenerative tendon and potentially promote healing. Some evidence for this has been found in clinical studies.

Surgical interventions involving the excision of degenerative tendon tissue has been used in the past if all conservative treatment has failed to resolve a patient’s symptoms after 12 months.

Physiotherapy treatments

As previously mentioned, a combination of physiotherapy interventions has been found to be more effective then corticosteroid injections in the long term for improving pain and function
in patients with common extensor tendinopathy. Physiotherapy interventions which show some evidence of success and may be used in combination include taping and bracing, stretching of the wrist extensors, soft tissue massage, dry needling, mobilisation of cervical and thoracic spine as well as eccentric and concentric loading programs.

Physiotherapists will also help to identify and correct any predisposing factors before introducing a graded return to activity. The rehabilitation for this injury is unlikely to be quick
and patients need to be well educated that they although potentially time intensive, conservative treatment is more likely to be beneficial in the longer term.

Call Central Physio Bayswater on 9271 2477 for an assessment and diagnosis.