Study Aims:~Aim #1: The main objective of this study is to determine the efficacy of two manual therapy approaches (passive joint mobilization and mobilization with movement) on pain (measured with Visual Analogue Scale) and pain processing (measured with pressure pain threshold, temporal summation and conditioned pain modulation) in patients with chronic low back pain and see its results on short, medium and long term.~Aim #2: The secondary objective is to compare the effect of both manual therapy techniques with an inactive control group in terms of pain and pain processing.~Aim #3: Determine the efficacy of manual therapy on intervention groups on psychological outcomes as catastrophizing (Pain Catastrophizing Scale), kinesiophobia (Tampa Scale of Kinesiophobia) and depression (Beck Depressive Inventory) and compare them with control group.~Methodology Research Design: Randomized, longitudinal, experimental, prospective, parallel and double-blind study with patients with chronic low back pain.~Participants: Adults between 18-65 years old residing Comunidad de Madrid, all of whom were recruited personally for the study. All patients will read the information sheet explaining what the study will consist, as well as the informed consent form, which they will sign voluntarily beforehand.~Sample Size: The sample size will be calculated by means of the Gpower 3.0.18 computer program.~Randomization: Randomization will be done through the GraphPad software (GraphPad Software, Inc CA 92037 USA). Patients who meet the inclusion criteria and have none of the exclusion criteria will be entered into the study and the sample will be randomized to obtain three groups in opaque and sealed envelopes: A (passive joint mobilization), B (mobilization with movement) and C (control group).~Masking: The double-blind criteria are met, in which the subjects participating in the study will not know the group to which they were assigned, as well as the physiotherapist in charge of collecting the outcomes data.
Patients with chronic low back pain may have altered pain processing, making them vulnerable to pain or disability. It can be measured with test like pressure pain threshold, temporal summation or conditioned pain modulation. Manual therapy has shown improve this pain processing variables in other conditions (like knee osteoarthritis or lateral elbow pain), although the quality of the evidence is low in terms of temporal summation and controversial in terms of conditioned pain modulation. There are not studies that had investigated the impact of manual therapy techniques on pain processing in patients with chronic low back pain.