The mobilization is a passive oscillatory technique, applied over cervical region in the hypomobile cervical level, the patient will be in prone and the therapist standing at the head of the patients with his thumbs in opposition placed at the level of the facet of the hypomobile cervical vertebra. A posteroanterior(PA) oscillatory pressure is applied, through the thumbs, over the process of the hypomobile vertebra. This oscillatory mobilization, is performed at a frequency of 2Hz (with metronome control/steps) for 2 minutes and repeated 3 times. The rest time between each mobilization was 1 minute.

This is a manual therapy technique that consist of applied a sustain pressure over cervical hypomobile symptomatic level and request to patient a pain free movement.

For performs it, the therapist placed his thumbs on the articular process of that level. The patient sitting. Then, the subject had to perform actively the painful motion while the therapist guides the movement of that vertebra and resists it while returning to neutral. The strength applied was parallel to the plane of the joint, and the procedure was performed in 3 sets of 10 repetitions.

The ACROM is an instrument that assesses the active range of motion of the cervical segment and has been used in numerous studies to evaluate the results in manual therapy. Furthermore, it has proven to be a reliable method of measuring, providing a range of intra-meter reliability from 0.7 to 0.9 and a range of inter-meter reliability from 0.8 to 0.87. It consists of an inclinometers system. Gravitational inclinometers for flexion-extension and lateral flexion, and magnetic inclinometers for rotation. The patient, sitting in a chair with the goniometer placed over his head, is asked to perform analytical neck movements (flexion, extension, right lateral flexion, left lateral flexion, right rotation and left rotation) to the point of beginning of pain symptoms or, otherwise, to the fullest extent of mobility. Each movement is recorded three times to take the average.

Pressure pain threshold (PPT) was used in this study for measure the mechanical hyperalgesia. A digital algometer (FDX 25, Wagner Instruments, Greenwich, CT, USA) comprised of a rubber head (1 cm2) attached to a pressure gauge, was used to measure PPTs. Force was measured in kilograms/f (kgf). The measures were taken 3 times at the cervical spine (C2 spinous process), with an interval of 30 seconds between each of the measurements. An average of the 3 measurements was calculated to obtain a single value for each of the measured points in each of the assessments. The assessor localized the spinous process of C2.

All participants completed Spanish version 47 of trait subscale of State Trait Anxiety Inventory (STAI-T. The STAI-T has been found to possess adequate reliability (alpha coefficients of 0.93, test-retest reliability of 0.80) and validity.

The level of depressive symptomatology was measured by the Spanish version50 of Beck depression Inventory (BDI-II), a self-report measure which assess affective, cognitive, and somatic symptoms of depression. The BDI has shown good internal consistency both in original sample (alpha coefficient 0.90) and in Spanish population (alpha coefficient 0.92). In addition, both versions has an adequate validity

The Tampa Scale for Kinesiophobia, developed by Miller was used to assess fear of movement and injury. We used the original 17-items version, which has showed good psychometric guarantees.

To evaluate the subject's propensity to catastrophize about pain we used the Spanish version of Pain Catastrophizing Scale (PCS). This scale is a 13-item questionnaire designed to measure the three components of catastrophizing: rumination, magnification and helplessness, resulting this evaluation in a unique score