The aim of this research is to compare the effects of Graston Technique, active release technique and PNF stretching on hamstring flexibility in Patients with Knee Osteoarthritis. Randomized controlled trials done at Riphah International University, Islamabad.. The sample size was 45. The subjects were divided in three groups, 15 subjects in Graston Technique group, 15 subjects in active release technique group and 15 in PNF stretching group. Study duration was of 6 months. Sampling technique applied was non probability purposive sampling technique. Male and female patients greater than 30 years of age, with unilateral or bilateral OA of grade 1 and 2 in Kellegren and Lawrence criteria for knee OA, having UL/BL hamstring tightness, Pain > 3 on NPRS, ROM > 200 from AKE test were included.

Tools used in the study are NPRS, AKE test by goniometer, Lower extremity functional index (LEFI) and WOMAC.

Osteoarthritis (OA) is the most common form of arthritis, affecting an estimated 302 million people worldwide. It is expected that ten percent males and 18 percent females have knee or hip OA. It ranks as the fifth highest cause of years lost to disability in the whole population in high-income countries, and the ninth highest cause in low- and middle-income countries. In older people, OA is the utmost devastating musculoskeletal syndrome.

It is a long-term chronic disease characterized by the destruction of articular cartilage and underlying bone. The degeneration occurs due to disarrangement in the usual process of repair of a joint. When the process breaks the synchronicity, there is slow deterioration of the articular cartilage. As a result, the biomechanical influences on the joints are also changed due to loss of normal joint line of gravity. This ultimately leads toward symptomatic changes which are a focal loss of the cartilage covering the articular ends; loss of normal joint space requires for smooth grating, osteophyte formation in joint, and remoulding of bone on peripheral areas and along the articular sides. Signs and symptoms are pain, a restricted range of joint movement, reduced muscle strength, restricted activities of daily living (ADLs) and instrumental activities of daily living (IADLS), and reduced quality of life.

Exercise, weight loss in patients with knee and/or hip OA who are overweight or obese, self-efficacy and self-management programs, tai chi, cane use, hand orthoses for first carpometacarpal (CMC) joint OA, tibiofemoral bracing for tibiofemoral knee OA, topical nonsteroidal anti-inflammatory drugs (NSAIDs) for knee OA, oral NSAIDs, and intraarticular glucocorticoid injections for knee OA are strongly recommended for treatment purposes. One major problem for patients with knee OA is poor hamstring flexibility. The stretching of the hamstring is a necessary intervention in the management of the OA knee. Although research and clinical experience has shown that treatment of hamstring flexibility is important, there is no widely acceptable form of treatment that is agreed upon to successfully improve flexibility of hamstrings.

Instrument assisted soft tissue mobilization (IASTM) using Graston technique is a popular treatment for myofascial restriction. The IASTM treatment is thought to stimulate connective tissue remodeling through resorption of excessive fibrosis, along with inducing repair and regeneration of collagen secondary to fibroblast recruitment. In turn, this will result in the release and breakdown of scar tissue, adhesions, and fascial restrictions.

Active release technique (ART) is also a technique that involves breaking down adhesions and scar tissue which cause pain and dysfunctions. It involves a clinician using their thumbs or fingers to apply deep tension to a trigger point while the involved tissue is moved from a shortened to lengthened position both actively by the patient and passively by the clinician.

Proprioceptive Neuromuscular Facilitation (PNF) stretching technique is another technique utilized to improve muscle elasticity. This technique is specifically designed to stimulate mechanoreceptors and significant effect of static as well as PNF stretching on clinical symptoms of knee OA.

Inclusion Criteria:

• Aged > 30years. Both male & female. Uni/bilateral OA. Grade I or II OA. Uni/bilateral hamstring tightness ranging between 40 to 70 degrees of a straight leg raise.

Exclusion Criteria:

• Hamstring injury and strains within 2 months. Any skin infections History of any lower limb surgeries within last 6 months. Lumber disc herniation. Lower limb neurological compromise.