Myofascial syndrome: comparison between infiltration of trigger points treatment and oral medication (cyclobenzaprine)

Abstract

Objective: To compare the effects of the infiltration of “trigger points” with lidocaine at 1% with the use of cyclobenzaprine in the short term treatment of trapezius myofascial syndrome (SMF). Material and methods: Randomized controlled prospective study with a “blind” evaluating 38 patients with trapezius SMF. Intervention accomplished in the test group (IF) (n = 18): infiltration with lidocaine at 1% in at the most 06 trapezius ”trigger points”; in the control group (CB) (n = 20) 10 cyclobenzaprine mg/dia was supplied for 15 days. The patients were appraised in the time zero (T0), in seven (T7), fifteen (T15) and thirty days (T30). Evaluation instruments: visual analogue scale of global pain (VAS of global pain), visual analogue scale of pain to the digital compression of “trigger points” (VAS of pain to the compression), short-form McGill pain questionnaire. The evaluation of the interobserver reprodutibility (RI) was accomplished for VAS of pain to the digital compression. Results: The patients presented, in the initial evaluation, AN average of “trigger points” of 2,0 (± 0,5), “taut band” of 3,05 (± 0,8) and to “tend spots” of 4,64 (± 1,15). The RI for VAS to the compression was shown satisfactory (pearson > 0,8). It was observed the largest variation (p > 0,05) of the pain score (McGill) in the IF, larger variation of the type pain and larger incidence of side effects in the CB. Both groups showed improvement at the end of the evaluation (p < 0,05). The average of the variations of VAS of global pain in T7 (-24,2% ± 62,8 CB X -40% ± 50,9 IF p = 0,19), T15 (- 37,6% ± 48,4 CB X -50% ± 44,8 IF p = 0,3) and T30 (-50% ± 60 CB X -70,8% ± 44,7 IF p = 0,14) it was higher in the IF, however without statistical significe. This tendency was also observed in the average of VAS variations of pain to the digital compression on T7 (-26,8% ± 35,34 CB X -46,5% ± 44,4 IF p = 0,24), on T15 (-38,8% ± 38,2 CB X -56,2% ± 34,3 IF p = 0,44) and on T30 (-46,6% ± 38 CB X -53% ± 34,4 IF - p = 0,38), however, once again without statistical significance. Conclusion: The similarity between the effect of the cyclobenzaprine an the infiltration of the trigger points allows the indication of the first in the patients’ treatment with trapezius SMF and it questions the invariable indication of the infiltration of trigger points.