C1-C2 is the most mobile segment of the spine and its dysfunction is frequently associated to cervical pain and headache. However, serious neurovascular adverse effects have been documented through direct treatment of C1-C2 segment. Although indirect treatment via adjacent segments and avoidance of end range of rotation and extension have been recommended for a safer and effective cervical treatment, there is no scientific evidence of the effectiveness of the indirect treatment approach in the cervical neutral position for C1-C2 hypomobility.

Due to that, the investigators designed a randomized controlled trial to compare the short-term effects in the Flexion Rotation Test (FRT) of a translatoric mobilization of C0-C1, a translatoric mobilization of C7-T1 and a control group in subjects with C1-C2 hypomobility.The primary hypothesis is that C0-C1 dorsal glide mobilization applied in the neutral cervical position can recover the C1-C2 rotational range of movement in subjects with upper cervical hypomobility.

Inclusion Criteria:

• FRT with less than 32º or asymmetry of 10º between right and left, whenever one of the sides does not exceed physiological C1-C2 ROM (45º)
• Indication of grade III mobilization in C0-C1 and C7-T1 segments
• Aged 18-66
• Signed informed consent

Exclusion Criteria:

• Contraindication to manual therapy and red flags according to Rushton et al. (2012)
• Pain presence at the beginning or during the study
• Cervical treatment during the last three months
• Inability to tolerate FRT
• Involvement in litigation or compensation