Comparing different diagnostic tests to determine what back problem patients may have: A study protocol

INTERVENTION: Participants consent to participate in the study and have their medical history and physical examination in order to confirm eligibility. Participants undergo the treatment session. This starts with an assessment of muscle dysfunction using the modified ankle rigidity test, followed by the leg length inequality test with the motion capture device. Next, treatment is applied with the mechanical chiropractic device applied in their neck area according to some specifications and to the criteria of the main assessor. After each application or attempt, the assessor uses the modified ankle rigidity test to evaluate changes. If no changes are observed, a second attempt is carried out and so on. If changes are observed, the assessor stops treatment and performs the leg length inequality test. After data is recorded, the assessor and the subject go to the X‐ray clinic (Gabinet Mèdic de Diagnosi i Tractament)) to take the radiographic view. The assessor is blinded to the results by not seeing the X‐ray at any time. They only position the patient, following similar instructions as described for this purpose and the clinic X‐ray technician takes the radiograph. The radiographic equipment is regularly aligned by the clinic owners. The results are kept in the X‐ray clinic and at the end of the study they are sent to the independent assessor for evaluation. Then, all the results will be sent to the statistician for compilation. At this point, there is no follow up for participants except for continuing care under main assessor's private clinic if they decide to. CONDITION: Musculo‐skeletal ; Musculoskeletal Diseases ; Musculo‐skeletal PRIMARY OUTCOME: Muscle rigidity is measured using the modified ankle rigidity test and Ashworth scale at baseline and after the treatment. SECONDARY OUTCOME: 1. Leg length discrepancy is measured in sub‐millimeters using the leg length inequality test at baseline and after the treatment; 2. Degrees of rotation of the atlanto‐occipital joint are measured using radiographic views at baseline and after treatment; INCLUSION CRITERIA: 1. Present or past history of back pain 2. Any gender aged from 18 to 70 years old 3. Consent to participate in the study