Background:

Tennis elbow, also known as lateral epicondylitis, is the inflammatory status of insertion site of common extensor tendon to humerus. It is usually related to overuse of local muscle. Radial extracorporeal shock wave therapy (rESWT) is a non-invasive physical treatment. It applies shockwave energy to the lesion site, enhancing the growth of microvascularity, inducing tissue repair, and thus relieving the symptom.

The purpose of this study is to understand the therapeutic effect of rESWT to tennis elbow.

Material and Methods

• Subjects: 30 patients will be recruited from outpatient department of physical medicine and rehabilitation department.
• Duration: 2013.09.01-2015.05.31
• Methods: The patients will be randomly divided into the experimental group and the control group through the draw, with 15 patients in each group. Patients in the experimental group receive rESWT plus routine rehabilitation program. Patients in the control group receive sham shockwave therapy plus routine rehabilitation program.
• Assessment: Before the therapy starts, patients who match the inclusion criteria will be evaluated using tools mentioned below:
• General data: age, sex, body height, body weight, affected side, medical history
• Assess upper extremity function and symptom with Disabilities of the Arm, Shoulder and Hand Questionnaire (DASH)
• Assess severity of pain with Visual Analogue Scale (VAS)
• Assess grip strength with grip strength dynamometer
• Measure the size of tear (if any) of common extensor tendon through ultrasonography, and assess the texture of common extensor tendon through real-time sonoelastography (RTS)

Patients will be followed up 6 weeks, 3months, and 6 months after therapy starts. They will be re-assessed of upper extremity function and symptom, severity of pain, grip strength, and presentation on ultrasonography and RTS.

Inclusion Criteria:

• Aged > 18 years old
• Lateral elbow pain lasting > 3 months
• Pain induced by direct compression on the lateral epicondyle or common extensor tendon, resistant wrist extension and pronation in the elbow extension position, or static stretching of common extensor tendon through the palmer flexion in wrist pronation and elbow extension position

Exclusion Criteria:

• Generalized inflammatory arthritis (e.g., rheumatic arthritis)
• Pain at the proximal part of involved arm (e.g., shoulder pain, neck pain)
• Pain other than elbow pain at the involved arm
• Abnormal neurogenic symptom over the involved arm (e.g., radicular pain, hands numbness, hemiplegia)
• Wound or skin lesion at the elbow of the involved arm
• Pregnancy
• Severe local or systemic infection
• Malignancy
• Coagulopathy
• Cardiac pacemaker
• History of surgical treatment at the elbow of the involved arm
• Non-steroid anti-inflammatory drug (NSAID) use orally or topically at the elbow of the involved arm in the past week
• Local steroid injection at the elbow of the involved arm in the past 3 months
• Oral steroid use in the past 6 weeks
• Refusal to sign the informed consent
• Impairment in self-expression (e.g., dementia, aphasia)
• Inability/unwillingness to participate in all the measurements.