Strength and range of motion in the contralateral side to pain and pain-free regions in unilateral chronic non-specific neck pain patients.

To determine if strength and range of motion (ROM) deficits are present in patients with unilateral chronic neck pain (CNP) at contralateral side to pain (CSP) and at other regions.Forty-nine patients with unilateral CNP and 98 asymptomatic subjects participated in this case-control study. ROM and muscle strength of the cervical, shoulder, trunk and hip regions were assessed bilaterally using inclinometer and dynamometer, respectively.CNP patients demonstrated reduced cervical, shoulder and trunk ROM in their ipsilateral side to pain (ISP) comparing the asymptomatic participants(P<0.05). The ISP cervical and shoulder ROM were also significantly lower than the CSP (P<0.05). Significant differences were also observable in the CSP comparing the asymptomatic group (P<0.05). Cervical, shoulder and scapulothoracic muscles were found weaker both in the ISP and CSP comparing the asymptomatic group (P<0.05). ISP and CSP hip flexors were also found to be significantly weaker than the asymptomatic group (P<0.01).The results revealed ROM and strength deficits in the pain-free regions of the body in unilateral CNP patients. Findings support the regional interdependence theory and emphasize the need for managing seemingly intact neighboring and more remote regions in unilateral CNP patients.