Background Patients with craniocervical pain have shown reduced performance in the craniocervical flexion test (CCFT). However, there is limited evidence of other possible kinematic alterations not assessed in the context of the CCFT. Previous studies on other functional or planar movements have reported alterations in sensorimotor control (e.g., range of motion [ROM], velocity, or smoothness) in subjects with neck pain. The objective of this study was to explore the association between sensorimotor control variables associated with craniocervical flexion movement and different characteristics related to pain, age, disability, and fear of movement in individuals with non-traumatic chronic neck pain and asymptomatic controls. Methods This was an observational, cross-sectional study in patients with non-traumatic neck pain and asymptomatic participants. Regression models were used to assess whether descriptive characteristics of the sample, including: (a) age, (b) intensity of pain, (c) neck disability, (d) chronicity of pain, and (e) fear of movement could explain sensorimotor control variables such as ROM, velocity, jerk, head repositioning accuracy, and conjunct motion. All these variables were recorded by means of light inertial measurement unit sensors during the performance of three maximal repetitions of full range craniocervical flexion in the supine position. Results A total of 211 individuals were screened and 192 participants finished the protocol and were included in the analyses. Participants had an average age of 34.55 ± 13.93 years and included 124 patients with non-traumatic neck pain and 68 asymptomatic subjects. Kinesiophobia partially explained lower craniocervical flexion ROM (p = .01) and lower peak velocity in flexion (P < .001). Age partially explained increased craniocervical extension ROM (P < .001) and lower peak velocity in flexion (P = .03). Chronicity partially explained increased lateral flexion conjunct motion (P = .008). All models showed low values of explained variance (< 32%) and low absolute values of regression coefficients. Conclusions This study did not find a clear relationship between population characteristics and sensorimotor control variables associated with the craniocervical flexion movement. Kinesiophobia might have some association with reduced ROM in craniocervical flexion, but further research in this field is needed in large samples of patients with higher levels of kinesiophobia pain or disability.

IntroductionNeck pain is a very common musculoskeletal disorder associated with high socioeconomic costs derived from work absenteeism and medical expenses. Previous studies have suggested that patients with neck pain of different origins present sensorimotor control impairments compared with the asymptomatic population. However, there is a small number of published studies focusing on these with conflicting results. In addition, the existing methodological limitations highlight the need for more and better quality studies. Moreover, longitudinal studies are necessary to investigate whether changes in pain or disability in individuals with chronic neck pain over time associate with changes in cervical sensorimotor control.Methods and analysisThis is a descriptive, observational, longitudinal, prospective study consecutively enrolling 52 patients with non-specific neck pain and 52 age-matched asymptomatic participants.Intensity of pain, neck disability, duration of symptoms, topography of pain and comorbidities will be registered at baseline. Sensorimotor control variables including active range of motion, movement speed, acceleration, smoothness of motion, head repositioning accuracy and motion coupling patterns will be recorded as primary outcomes by means of inertial sensors during the following tests consecutively performed in two sessions separated by 12 months: (1) kinematics of planar movements, (2) kinematics of the craniocervical flexion movement, (3) kinematics during functional tasks and (4) kinematics of task-oriented neck movements in response to visual targets.Secondary outcomes will include: (1) Regular physical activity levels, (2) Kinesiophobia, (3) Symptoms related to central sensitisation and (4) The usability of the inertial measurement unit sensor technology.Ethics and disseminationThis study was approved by the Research Ethics Committee of CEU San Pablo University (495/21/39). Patients will be recruited after providing written informed consent and they will be able to withdraw their consent at any time. Only the study investigators will have access to the study data. The results will be disseminated through scientific publications, conferences and media.Trial registration numberNCT05032911.