This randomised, controlled, double-blind experimental study is designed to evaluate the efficacy of a standardised manual physiotherapy protocol for treating lateral epicondylalgia of the humerus, commonly known as 'tennis elbow'. The study will compare the results for patients receiving active treatment with those for a control group who will follow a watchful waiting approach. Secondary objectives include analysing the relationship between pain, grip strength and joint mobility in the elbow and cervical spine. A sample of healthy subjects will also be included to establish baseline data and measure the effects of the protocol in an asymptomatic population.

Inclusion Criteria:

• Clinical diagnosis of epicondylalgia.
• Pain on palpation of the epicondyle. Performed and measured with an algometer.
• Pain on isometric contraction against resistance of the wrist extensors (epicondylar muscles).
• Pain on contraction of the wrist and finger flexor muscles or pressure force. Performed and measured with a JAMAR manual pressure dynamometer.
• Pain on stretching-elongation of the epicondylar muscles or Mills test (wrist and finger flexion, forearm pronation and elbow extension).
• Pain during prono-supination movements of the forearm and/or flexion-extension of the elbow.

Subjects must meet a minimum of 4 of the 5 inclusion criteria to be part of the study. In addition to the inclusion criteria, subjects must be between 18 and 60 years of age, able to answer questionnaires in Spanish, and give their written consent.

Exclusion Criteria:

• History of elbow fractures or cracks during the last twelve months.
• History of elbow dislocations and/or subluxations during the last twelve months.
• History of elbow surgery.
• Congenital and/or acquired elbow deformity.
• Organic elbow condition (osteoarthritis, arthritis).
• Radio-humeral bursitis.
• Radio-humeral chondromalacia.
• Tear of the annular ligament.
• Detachment of the periosteum.
• Tendon rupture in the elbow.
• Metabolic or infectious arthropathy.
• Cervical pathology or cervicobrachial neuralgia.
• Bilateral elbow pain.
• Radial nerve compression neuropathy.
• Participating in professional or amateur sports.
• Having received treatment with injections, physiotherapy or manual physiotherapy for your condition during the previous 6 months.
• Pain lasting less than 6 weeks.
• Receiving other treatment during the study.
• Patient absenteeism from treatment. We define patient absenteeism as missing a treatment session and/or measurement. We do not count delays of less than 2 days in a treatment session and/or measurement as absenteeism.