A triple-blind cross-sectional observational study is designed where subjects with low back pain will be selected and blinded to recieve the Magnetic Tape® (tape with magnetic effects of less than 2 Gauss) or placebo Tape. Likewise, the evaluator who puts the Magnetic Tape® does not know what material he is using, as it is supplied by another researcher. The statistician will also be blinded.~The recommendations of the Reporting of Observational Studies in Epidemiology (STROBE) will be followed. All participants will receive a participant information sheet and sign informed consent. Patients aged 18 to 65 years with low back pain will be recruited from different private clinics in the city of Valencia, Spain.~The hypothesis is that when Magnetic Tape® comes into contact with electromagnetic fields such as those generated by living beings, due to the movement of electrical charges (ions), as defined by Ampere's Law, the domains of the tape are oriented or aligned in parallel with the external magnetic field creating a magnetic flux with a north pole and a south pole. This generated field in turn produces a magnetic induction proportional to the variation of the magnetic flux, as defined by the Faraday Law.~This electric potential produces a redistribution of the electric charge (ions) generating a magnetic field due to the orientation of the tape domains, then exerting a force on the moving charges within the electrolyte.~Physiological, Lorentz's Law, regulating Magnetic Tape® aberrant electromagnetic fields.~After signing the informed consent and data protection, the groups with low back pain will be formed that will receive the application of both Magnetic Tape® and the intervention of a placebo tape. To avoid that the order of the intervention influences the results of the study, the subjects will be randomized into two different groups, Group A and Group B. Group A will receive Magnetic tape® and Group B will do the opposite. The next day the other tape will be applied.~The patient will be placed in the prone position and the spinous processes of T11 and L5 will be identified by marking them with a pen. Once L4 is located at the level of the iliac crests, the therapist will palpate the following spinous processes and will count down to the level of T11 and L5, and then mark it.~Later two strips of tape will be placed on the lumbar paravertebral skin. To measure ANS activity during this study the vortex from Micromedical will be used to capture the pupil diameter. Each participant will wear the goggles throughout the measurement phase and will be in a prone position (with the eyes in complete darkness). After the goggles are placed properly the subjects will remain in a quiet room for three minutes to accommodate to the room environment before the pupil measurement. After this, a 60 second pupil recording will be taken. This measurement will serve as the participant's baseline measurement. After the tape placement the pupil will immediately measured again for a duration of 60 seconds. After a 30 second break period in which the subject is able to blink and close the eyes a second 60 second measure of the pupil will be taken. These steps will be repeated so there will be a total of 4 post measure 60 second pupil measurements (post measure 1, 30 sec break, post measure 2, 30 sec break, post measure 3, 30 sec break, post measure 4). Regardless of what tape is used that will be the measurement sequence.~After signing the subject informed consent and data protection groups will be formed. There will be two groups. The first group will consist of spinal pain patients. This group will receive both a Magnetic Tape®, and the placebo tape intervention. The second group without back pain will be age matched to the spine group and will receive the Magnetic Tape®. The spine pain patients are given the two interventions on two different days and wills serve as their own control. To prevent the order of the intervention to influence the study results the subjects will be randomized into two different groups, Spine A and Spine B. Spine A will receive the Magnetic Tape® on their first visit and receive a kinesiology tape on their next visit. Spine B will do the opposite. The control group will only receive the intervention tape.~After this, the subject will be placed on a treatment table in the prone position. In this position, a physical therapist will provide posterior to anterior pressure applied at the spinous process and the segmental skin pinch test and it will be documented whether this pressure would cause any pain. If any pain is reported, the subject will be asked to rate this pain on a Numerical Pain Rating Scale (NPRS). The pressure was carried out from S3 to C2.~Neither application has to be painful.
The tape will be applied on the lumbar area bilateralemten to the spine without creating any tension.~Possible variation in the autonomic nervous system is assessed in the reaction of the pupils. A kinesiology tape was used as a placebo tape and the magnetic tape was used in a randomized experimental way.