The aim of the study is to compare the effectiveness between the suboccipital inhibition technique, the suboccipital inhibition carried out with the INYBI instrument and the suboccipital inhibition with the INYBI plus the upper cervical manipulation, all in patients with chronic mechanic cervicalgia, and to determine which of these techniques is the most effective in the variables studied. In order to do so, 96 subjects participated in the study, being assigned to the 3 intervention groups. We expected the combined treatment (INYBI instrument + upper cervical manipulation) to be the one to produce the best results.

Inclusion Criteria:

• Participants aged between 18 and 40 all diagnosed with chronic mechanic cervical pain with an evolution of at least 3 months and who show pain that increases with maintained postures, during movement and during spinal muscles palpation.

Exclusion Criteria:

• participants that can't read and/or fill in the informed consent, either due to a language and/or cognition alteration or age-related factors.
• subjects with psychological pathologies, such as hysteria, depression or anxiety.
• subjects that have received a manual treatment two months before the beginning of the clinical trial.
• subjects who have been recommended by a physician or an anesthetist to receive any type of analgesic, anti-inflammatory or neuromodulator medication, such as antidepressants, antiepileptics and benzodiazepines. If the patient took in this type of medication in an occasional way 72 hours before the beginning of the study, he/she could participate.
• the treatment and assessment techniques will be avoided if: fear to vertebral manipulation in the upper cervical area or positive Klein test and other integrity test of the vertebral artery, positive cervical instability test and positive Spurling test (foraminal compression test).