Relationship Between Proprioception and Endurance Functionality of the Cervical Flexor Muscles in Chronic Neck Pain and Asymptomatic Participants

The purpose of this study was to compare the relationship between flexion endurance capacity and joint position error in participants with or without chronic neck pain (CNP). Sixty-one CNP and 60 asymptomatic volunteers participated in this cross-sectional, case-control, and correlational analysis study. The measured variables included absolute and constant joint repositioning errors in the sagittal and horizontal directions, clinical flexor endurance test score, pain intensity, and neck disability index. The groups did not statistically differ in flexion endurance ( P >.05). The CNP group had a smaller absolute error on the right ( P <.01) and left ( P =.01) rotation and an overshooting error pattern in the flexion direction ( P <.05). But the asymptomatic group did not exhibit any over-/undershooting pattern tendency ( P >.05). Although flexion endurance was not correlated with any of the joint repositioning error components in either group, pain and disability scores were significantly correlated with left rotation absolute error ( r = –0.34 and ρ = –0.37, respectively). The clinical cervical flexor endurance test, ignoring the relative contribution of the deep and superficial groups of muscles, may not efficiently characterize CNP patients.