Effect of Chronic Mechanical Neck Pain on Isokinetic Characteristics of Rotator Cuff Muscles in Adults

Inclusion Criteria: Subjects were included according to the following criteria: * Thirty-three participants with Chronic Mechanical Neck Pain(CMNP) and Thirty-three healthy participants would be assigned into two groups; healthy control group (A) and CMNP group (B). * Right and left- handed subjects. * Both sexes between 18-29 years old * (0-4 mm) no pain, (5-44 mm) mild pain, (45-74 mm) moderate pain, (75-100 mm) severe neck pain on visual analogue scale . * Chronic neck pain \> 12 weeks . * They did not take any painkillers for the last 48 hours before assessment. Exclusion criteria: Subjects were excluded if they have any of the following: * Shoulder-related pain. * The existence of any anomalies in the neck and shoulder areas. * A history of trauma or severe illnesses such as diabetes, cancer, fibromyalgia, or any kind of tumor. * Disc herniation; history of identifiable structural injury. * Past incidents of whiplash injury. * Prior surgery; fractures. * Pregnancy. * Any prior rehabilitative therapy received during the last three months.