The goal of this randomized controlled clinical trial is to investigate the effects of blood flow restriction training on the parameters surrounding tennis elbow afflicted patients including pain, disability, and grip strength.

The main question this study aims to answer is:

1- Does blood flow restriction training offer significantly better effects on pain, disability, and grip strength when compared to conventional strength training without blood flow restriction in patients afflicted with tennis elbow? Research will compare two groups with tennis elbow where both will perform the same rehabilitation program consisting of conventional physical therapy for tennis elbow as well as a strength training program with the only difference being that one group will undergo blood flow restriction training while the other will not.

Lateral epicondylitis, commonly known as Tennis elbow, is a musculoskeletal condition characterized by pain at the lateral epicondyle due to repetitive forearm and hand movements. While it often improves over time, some cases may worsen. Diagnosis involves physical signs, including pain, decreased grip strength, tenderness, and pain during wrist flexion. Medical imaging such as MRI and clinical tests like Mills and Cozen's are used for confirmation.

According to Lenoir, Mares, Carlier (2019), physical therapy is the primary treatment, with exercises like eccentric muscle strengthening, deep friction massage, stretching, ultrasound, and laser therapy proving beneficial. Blood flow restriction training (BFR) has gained interest for enhancing strength and muscle mass. BFR involves partially restricting blood flow using a strap or cuff, inducing muscle hypoxia. Despite the unclear mechanism, BFR has shown positive effects on muscle tissue, possibly related to hypoxia and muscular acidosis.

The lack of studies on BFR's impact, especially on smaller muscle groups like fingers and wrists, creates a need for investigation. Given the commonality and impact of lateral epicondylitis symptoms, this study aims to compare the effectiveness between BFR training with standard PT exercises and standard PT alone in patients with lateral epicondylitis. Thus the purpose of this study is to prove that BFR training is more effective than standard physical training in improving the parameters surrounding tennis elbow.

The participants will be randomized into 2 groups. The standard physical therapy (group1) training consists of :1-ultrasound therapy, 2-laser, 3-deep friction massage followed by ice on the proximal attachment of the extensor tendon, 4-heat, 5-stretching of the wrist flexors and extensors, 6-strengthing of the wrist extensors combined with BFR.

(Group 2) will be treated with the same interventions excluding BFR training. Participants in both groups will be receiving treatment 2 times per week for 12 sessions.

Inclusion Criteria:

• Patients that were included in this study were diagnosed with lateral epicondylitis by a medical doctor for less than 3 months.
• Dominant hand was diagnosed with lateral epicondylitis.
• They were aged between 20 and 40 years old.
• With decreased grip strength and wrist range of motion.
• No history of physical therapy treatment for lateral epicondylitis for at least 6 months.

Exclusion Criteria:

• Patients with chronic diabetes.
• Any type of trauma or fracture in the upper extremities in the last 3 months.
• Patients with any vestibular problems.
• Patients with deep vein thrombosis (DVT).
• Patients with hypertension.
• Patients with cancer.