Joint mobilization is a manual therapy intervention, a type of straight-lined, passive movement of a skeletal joint that addresses arthrokinematics joint motion (joint gliding) rather than osteokinematics joint motion. It is usually aimed at a 'target' synovial joint with the aim of achieving a therapeutic effect. These techniques are used by a variety of health care professionals with specific training in manual therapy assessment and treatment techniques. IFOMPT defines joint mobilization as "a manual therapy technique comprising a continuum of skilled passive movements that are applied at varying speeds and amplitudes to joints, muscles or nerves with the intent to restore optimal motion, function and/or to reduce pain". The APTA Guide to Physical Therapist Practice defines mobilization/ manipulation as “a manual therapy technique comprised of a continuum of skilled passive movements that are applied at varying speeds and amplitudes, including a small amplitude/ high velocity therapeutic movement”. Joint mobilization is an example of a hands-on treatment and is a form of passive movement technique for musculoskeletal conditions. This technique, which is considered manual therapy, is usually performed by certified physical therapists. This usually involves applying force that would mimic the glide that happens in between the bones. Joint mobilization is usually done at a slow speed, with or without oscillations or a stretch. This technique is usually graded and is varied based on two factors: pain tolerance of the patient and the acuity of the patient’s condition. In comparison, manipulation technique is more aggressive using high velocity thrusts. The main aim of joint mobilization is to restore the normal joint play that might have been compromised by damage or injury. Normal motion of the affected joint will restored more quickly if it is addressed early in the treatment program. Also, mobilization is in cases when range of motion is lacking. The varying grades of joint mobilization are from grades 1-5. Grades 1-4 deals with the knee range of motion, starting from partial movement to end of range movement. Grade 5 is more of manipulation than mobilization.