Electroanalgesia in the therapeutic approach of the inspecific chronic neck pain in Primary Care. Randomised controlled trial.

IFC Definition: Interferential current therapy is the application of alternating medium- frequency current (4,000 Hz) ampli- tude modulated at low frequency (0–250 Hz).(Fuentes 2010, Physiotherapy 2010 90-9 1219-1238) IFC Adavntages: A claimed advantage of IFC over low-frequency currents is its capacity to diminish the imped- ance offered by the skin. Another advantage speculated for IFC is its ability to generate an amplitude- modulated frequency (AMF) parameter, which is a low-frequency current generated deep within the treatment area.(Fuentes 2010, Physiotherapy 2010 90-9 1219-1238) IFC Effects: Several theoretical physiological mechanisms such as the “gate control” theory, increased circulation, descending pain suppression, block of nerve conduction, and placebo have been proposed in the literature to support the analgesic effects of IFC.(Fuentes 2010, Physiotherapy 2010 90-9 1219-1238) Our study is tries to get scientific evidence of the IF Currents effects over Chronic Neck Pain's Patients combined with a program of supervised therapeutic exercises. The intervention will be provided by a physiotherapist with more than 10 years experience. The duration of each session will be aproximately one hour and half. The number of sessions administried to each participant will be 10. The aplication of the IF currents will be one on one and the exercises will be provided in group sessions. IFC Parameters: Treatment with interferential currents, bipolar method 4000 Hz carrier frequency and 60 Hz AMF with a modulation frequency of 90 Hz, with electrodes 5x10 cm2 placed in opposition to the neck (C5-C6-C7), during 25 minutes. The intensity (voltage) of the IFC will be adapated to the sensitivity of each patient. The current intensity during the treatment time must be increased 3 to 5 times, within the limits of patients' perception without exceeding the threshold of excitability and pain. The increased intensity is intended to retard the aparition of accommodative phenomena . Patients will receive 10 sesions from monday to friday during two weeks. The Physiotherapist will register the attendance at sessions. This group will receive also a supervised exercises program before the IFC treatment. Patients undertake the supervised exercise group treatment early in the morning (8:30h) and receive treatment with interferential currents throughout the morning. The minimum interval between the completion of the exercises will be one hour (The first patient of this experimental group will end exercises at 9:30 and will start IFC tratment at 10:30) and up to four (The last patient will end exercises at 9:30 and will start IFC tratment at 13:30) SUPERVISED EXERCISES PARAMETERS: The supervised exercises will include: 1) Ergonomic advice on reducing repetitive motion and / or maintained positions. 2) Program active physiotherapy for neck and shoulder muscles including: a. Active stretching exercises b. Isometric muscle strengthening exercises c. Reeducation program oculo cervico kinetic d. Homeworks .The exercises will be practised in a very slow way. It will not increase significantly the heart rate. Our objective is to induce relaxation and pain relief at the same time that we improve the neck muscles' flexibility and strength Patients will receive 10 sesions of supervised exercises in groups from monday to friday during two weeks. The duration of the sessions will be one hour The Physiotherapist will register the attendance at sessions. In order to encourage the adherence to the home exercises, the information provided by the physiotherapist will be clear, concise and they will ask patient after each session how do they feel after the realization of the exercises the day before and if they have any doubt about them. The physical therapist will also ask patients to write a daily in order to detect questions during the intersessional period and to encourage the daily practice during the next months. The physical therapist will try to convey the difference between a bearable pain of analytical stretching (which disappears quickly after the execution of exercises) and persistent chronic pain characteristic of neck pain. It will also encourage them to take a pain diary to encourage them to see how the crisis periods will inter spacing for more time thanks to the implementation of the program of home exercises. The aim is to demonstrate or better manage their self care and self-efficacy They will be asked to complete the same exercises at home at least over 30 to 45 minutes once a day , during the two weeks of treatment and at least during ten to twelve weeks after.