Combined Shockwave Therapy Versus Focused Shockwave Therapy in Patients With Lateral Epicondylitis

1. To determine the best effective modality between combined (focused and radial) and focused shockwave therapy for treatment of lateral epicondylitis regarding pain.
2. To determine the best effective modality between combined (focused and radial) and focused shockwave therapy for treatment of lateral epicondylitis regarding hand function.
3. 1. To determine the best effective modality between combined (focused and radial) and focused shockwave therapy for treatment of lateral epicondylitis regarding grip strength.

Lateral epicondylitis, also known as "tennis elbow", is a common disease present in clinical practice. It affects 1% to 3% in the general population which can reach up to 29% in certain occupations with repetitive wrist movements. It can cause a significant functional decline with a great psychological and economic impact.

Major symptoms include decreased grip and upper-extremity strength along with pain and inflammation originating from the lateral elbow. The pathogenesis of lateral epicondylitis is still controversial, but it is known that not only the tendon of the extensor carpi radialis brevis (ECRB) muscle but also the annular ligament, lateral capsule, radial nerve and some bands of the extensor digitorum communis muscle are involved.

It was originally thought that the cause of lateral epicondylitis was an inflammatory process, which would then result in the symptoms. However, histological studies have demonstrated that, through repetitive injuries at this site, there is a degenerative process and a failure of repair in the ECRB tendon. This is more pronounced than inflammation in other structures.

A variety of therapeutic techniques have been proposed for the appropriate management of patients with lateral elbow tendinopathy including exercise, orthotics, manual therapy, passive modalities, acupuncture or a combination of them.

However, the effectiveness of each treatment option remains debatable. Extracorporeal shockwave therapy (ESWT) is a popular method in the management of common tendinopathies and has been proposed as an effective supplement to other non-invasive therapies. There are two types of extracorporeal shockwave therapy: focused shockwave therapy (FSWT) and radial shockwave therapy (RSWT). Waves that are generated for focused and radial ESWT have very different physical characteristics.

FSWT has focused on a pressure area concentrated on a definite place, and can be adjusted at definite depths in the selected tissues, where the higher pressure is touched. Focused type of shockwave is directed by the reflection at definitive areas into the body of patients, and the waves are generated from a wide arc, hence the amount of energy discrete is minimal at the point of real wave generation. The radial shock wave therapy has been attributed to the scattering pressure zone of RSWT apparatus, which arrives at the source as the highest pressure, and didn't require a certain distance in human body and the omitted waves radiate within the tissues, and influence a large area, but they do not deeply reach the thick tissues as that in focused wave therapy, therefore RSWT is effective for treating superficial lesions that assist the deep-tissue stimulation like backs and muscles.

Eligibility Criteria:
Inclusion Criteria:

* Patient age between 18 - 55 years old.
* BMI \< 35
* Males and Females
* Painful chronic tennis elbow during at least 3 previous months identified by positive Mill"s, Maudsley"s and Cozen"s tests.
* Painful palpation of the lateral epicondyle.
* Painful resisted middle finger and wrist extension (Maudsley's test).

Exclusion Criteria:

* Local infection.
* Malignancy.
* Elbow arthritis or instability.
* Pronator-Teres syndrome.
* Generalized polyarthritis.
* Neurological disorders (Stroke and Parkinson"s disease).
* Radial-nerve entrapment.
* Physical therapy and/or a corticosteroid injection administered within the previous six weeks.
* Pregnancy.