Description

Lateral epicondylitis is a form of tendinitis characterized by pain at the attachment site of the common extensor tendons of the wrist to the lateral epicondyle, resulting from inflammation and degeneration (Kraushaar \& Nirschl, 1999). It is most commonly seen in individuals aged 40-59, with a prevalence of 1.3% (Zhang et al., 2024). Common risk factors include female gender, obesity, a history of smoking, repetitive activities, and ipsilateral rotator cuff dysfunction (Shiri et al., 2006). Typically, pain on the lateral aspect of the elbow and forearm, restricted range of motion in the elbow and wrist joints, decreased muscle strength, and loss of function may be observed due to repetitive forearm supination/pronation and wrist extension (Shiri \& Viikari-Juntura, 2011; G et al., 2024).

Treatment options include medical (oral and topical nonsteroidal anti-inflammatory drugs, local corticosteroid injections), conservative (cryotherapy, orthoses, electrotherapy, etc.), and surgical methods. Among conservative methods, Extracorporeal Shock Wave Therapy (ESWT) is frequently preferred (Lai et al., 2018). ESWT is a non-invasive method that utilizes high-frequency acoustic waves for therapeutic purposes in target tissues. This method supports tissue regeneration by enhancing angiogenesis at the tendon-bone junction through the stimulation of vascular endothelial growth factors and nitric oxide synthesis, and reduces pain by inhibiting pain receptors (Yoon et al., 2020). Additionally, it triggers the release of lubricin, which facilitates tendon repair and gliding by stimulating tenocyte proliferation through increased expression of TGFβ1 and IGF-1 (Zhang et al., 2011). The literature has demonstrated that ESWT has effects on lateral epicondylitis, such as alleviating pain, shortening recovery time, increasing grip strength, and enabling patients to return to their daily activities (Murat et al., 2024; Pettrone \& McCall, 2005).

Another conservative method used in the treatment of lateral epicondylitis is Blood Flow Restriction Therapy (BFR). In this method, arterial blood flow is partially restricted and venous return is blocked by applying an external device (tourniquet or adjustable-pressure cuff) to the proximal part of the extremity (Patterson et al., 2019). This causes the targeted muscle group to work in an ischemic, hypoxic environment, triggering a significant increase in muscle mass and strength by activating fast-twitch muscle fibers (Gorgey et al., 2016; Scott et al., 2014). Studies investigating the effects of BFR on lateral epicondylitis have shown that it reduces pain, increases grip strength, and contributes to functional improvement (Karanasios et al., 2022; Kinandana et al., 2023).

In the literature, the effects of both methods on lateral epicondylitis have been examined separately, but their efficacy has not been compared. Therefore, the aim of our study is to compare the efficacy of extracorporeal shock wave therapy (ESWT) and blood flow restriction therapy (BFR) in patients with lateral epicondylitis. By comparing different treatment methods that can be used in the management of lateral epicondylitis symptoms, our study will contribute to the use of more personalized and effective treatment strategies by healthcare professionals and will serve as a guide for future research.