The frequency of lateral epicondylitis (LE), one of the most common causes of elbow pain, has been reported to be 1-3%. It is usually seen between the ages of 40-50 and the dominant side is more frequently affected. The most common cause of elbow lateral pain in adults is LE (1,2). Pain that occurs in LE and radiates to the humerus and forearm is characteristic of this disease. (3). The diagnosis of lateral epicondylitis is usually made clinically. Dorsiflexion of the wrist against resistance, pressure on the lateral epicondyle and firm grip of an object causes pain radiating to the forearm. (4). With appropriate conservative treatments, 75-90% relief has been reported in patients with LE (1). Chronic symptoms develop in 5-10% of the patients. Various treatments have been tried to reduce the pain of the patient and increase the functions in LE, which restricts daily life activities. Although many treatment methods are used in the treatment of LE disease, it is controversial which is the most effective method. Extracorporeal Shock Wave therapy (ESWT), peloidotherapy, NSAID, corticosteroid injection, cold application, fascia loosening, electrotherapy applications, kinesio band, iontophoresis, splint, orthosis, acapuntur, ultrasound therapy, deep friction massage, exercise, manipulation, mobilization, laser, Botulinum toxin injection, tenotomy, and autologous blood injections are among the recommended treatments (4-9). Although there are so many different treatment methods in the treatment of lateral epicondylitis, there is no consensus on which one is the most effective and successful.

Peloids (medicinal mud) are organic or inorganic substances formed as a result of geological and / or biological events. They can be found in nature as fine particles, or they are made into small, fine particles by some pre-preparation processes. (10). Peloidotherapy is a special balneotherapy method made with natural muds (11). It is especially used in the treatment of diseases such as degenerative joint diseases, soft tissue rheumatism, lumbar discopathy, cervical discopathy, chronic back and neck pain, joint pain. Scientific studies on peloid treatment both in Turkey and abroad have shown that patients have reduced pain (12), improved physical functions, increased quality of life, and decreased pain medication use (12-15). A recent study demonstrated the effectiveness of peloidotherapy in LE. (16). Ökmen et al. In this study, the effectiveness of peloidotherapy and elbow bandage in the treatment of LE was compared. (16). This study remains the only one investigating the effectiveness of peloidotherapy in the treatment of LE.

Shock wave therapy (extracorporeal shock wave therapy, Extracorporeal Shock Wave Therapy-ESWT) is a new orthopedic treatment method based on focusing high amplitude sound waves on the desired area of the body and providing treatment there. (17). ESWT creates a cavitation effect in deep tissue by creating capillary microrupture, chemical mediator leakage, and neovascularization in damaged tissue with low or high energy options (18). Successful results have been reported with ESWT treatment in 48-73% of cases with recurrent LE with non-surgical methods (19). Due to its non-invasive nature and low complication rates, the use of ESWT in LE treatment is gradually increasing (20). Some authors state that ESWT has lateral LE effect (20). Some authors reported that ESWT is not in the treatment of LE (21).

Investigator did not find a study comparing ESWT and Peloidotherapy methods in the treatment of LE in the literature. In this thesis, our aim is to compare the effectiveness of peloidotherapy and ESWT methods used in the treatment of LE with a prospective clinical study.