Tennis elbow

Tennis elbow, also known as lateral epicondylitis or enthesopathy of the extensor carpi radialis origin, is an

Enthesopathies are idiopathic, which means that science has not yet determined the cause.^[7] Enthesopathies are most common in middle aged individuals (ages 35 to 60).^[8]

It is often stated that the condition is caused by excessive use of the muscles of the

• Pain on the outer part of the elbow (lateral epicondyle)
• Point tenderness over the lateral epicondyle—a prominent part of the bone on the outside of the elbow
• Pain with resisted wrist extension or passive wrist flexion^[16]

Symptoms associated with tennis elbow include, but are not limited to, pain from the outside of the elbow to the forearm and wrist pain during extension of wrist.^[17]

Terminology

The term "tennis elbow" is widely used (although informal), but the condition should be understood as not limited to tennis players.^[18][19] Historically, the medical term "lateral epicondylitis" was most commonly used for the condition, but "itis" implies inflammation and the condition is not inflammatory.^{[3][18][19][20][21]}

Since histological findings reveal noninflammatory tissue, the terms "lateral elbow

Enthesopathy of the extensor carpi radialis brevis origin is idiopathic, meaning that it has no known cause.^[26]

Traditionally, people have speculated that tennis elbow is a type of repetitive strain injury resulting from tendon overuse and failed healing of the tendon, but there is no evidence of injury or repair on histopathology, and misinterpretation of painful activities as a source of damage is common.^[27]

Other speculative risk factors for lateral epicondylitis include taking up tennis later in life, unaccustomed strenuous activity, decreased

Pathophysiology

Histological findings are of mucoid degeneration: disorganized collagen, increased extracellular matrix, and chondroid metaplasia. There is no evidence of inflammation or repair.

Diagnosis is based on symptoms and clinical signs that are discrete and characteristic. For example, the extension of the elbow and flexion of the wrist causes outer elbow pain. There is point tenderness at the origin of the extensor carpi radialis brevis muscle from the lateral epicondyle (extensor carpi radialis brevis origin).^[16]

Cozen's test

Cozen's test is a

Medical imaging is not necessary or helpful.[30]

Radiographs (X-rays) may demonstrate calcification where the extensor muscles attach to the lateral epicondyle.

Longitudinal sonogram of the lateral elbow displays thickening and heterogeneity of the common extensor tendon that is consistent with tendinosis, as the ultrasound reveals calcifications, intrasubstance tears, and marked irregularity of the lateral epicondyle. Although the term “epicondylitis” is frequently used to describe this disorder, most histopathologic findings of studies have displayed no evidence of an acute, or a chronic inflammatory process. Histologic studies have demonstrated that this condition is the result of tendon degeneration, which replaces normal tissue with a disorganized arrangement of collagen. Colour Doppler ultrasound reveals structural tendon changes, with vascularity and hypo-echoic areas that correspond to the areas of pain in the extensor origin.[33]

Treatment

The natural history of untreated enthesopathy is resolution over a period of 1–2 years.

Stretching and isometric strengthening are the most common recommended exercises. The muscle is stretched with the elbow straight and the wrist passively flexed. Isometric strengthening can be done by pushing the top of the hand up against the undersurface of a table and holding the wrist straight.[36]

Orthotic devices

Orthosis is a device externally used on the limb to improve the function or reduce the pain. Orthotics may be useful in tennis elbow; however, long-term effects are unknown.^[37] There are two main types of orthoses prescribed for this problem: counterforce elbow orthoses and wrist extension orthoses. Counterforce orthosis has a circumferential structure surrounding the arm. This orthosis usually has a strap which applies a binding force over the origin of the wrist extensors. The applied force by orthosis reduces the elongation within the musculotendinous fibers. Wrist extensor orthosis maintains the wrist in the slight extension.

Speculative treatments

Other approaches that are not experimentally tested include eccentric exercise using a rubber bar, joint manipulation directed at the elbow and wrist, spinal manipulation directed at the cervical and thoracic spinal regions, low level laser therapy, and extracorporeal shockwave therapy.^{[38][39][40][41][42]}

Medication

Although anti-inflammatories are a commonly prescribed treatment for tennis elbow, the evidence for their effect is usually anecdotal with only limited studies showing a benefit.

Surgery

Surgery is an option.^[51][52][53] Surgical methods include:^[54]

• Lengthening, release, debridement, or repair of the origin of the extrinsic extensor muscles of the hand at the lateral epicondyle

Surgical techniques for lateral epicondylitis can be done by

Evidence from imaging studies suggests that about 1 in 5 humans have detectable enthesopathy of the extensor carpi radialis brevis origin in their lifetime.[58] Symptoms likely vary and are self-limited. The signal changes on MRI seem permanent. There is no evidence that specific occupations or activities are associated with enthesopathy.^[59]

Symptoms of lateral epicondylitis

Symptoms suggestive of lateral epicondylitis are present in about 1% of the adult population and are most common between ages 40 and 60.^[59] The prevalence varies somewhat between studies, likely as a result of varied diagnostic criteria and limited reliability between different observers.^[59] The data regarding symptoms of lateral epicondylitis in relation to occupations and sports are inconsistent and inconclusive.^[59] The shortcomings of the evidence that addresses the relationship between symptoms and occupation/sport include: variation in diagnostic criteria, limited reliability of diagnosis, confounding association of psychosocial factors, selection bias due to a high non-response rate, and the fact that exposures are usually by subjective patient reports and symptomatic patients might receive greater exposure.

History

German physician F. Runge^[60] is usually credited for the first description of the condition, calling it as "writer's cramp" (Schreibekrampf) in 1873.^[61] Later, it was called as "washer women's elbow".^[62] British surgeon Henry Morris published an article in The Lancet describing "lawn tennis arm" in 1883.^[63][60] The popular term "tennis elbow" first appeared the same year in a paper by H. P. Major, described as "lawn-tennis elbow".^[64][65]

See also

• Golfer's elbow
• Olecranon bursitis
• Radial tunnel syndrome
• Repetitive strain injury

References