Effectiveness of spinal manipulative therapy in the treatment of mechanical thoracic spine pain: A pilot randomized clinical trial

Abstract

Background: To date, no substantiated studies have been performed to investigate the efficacy of spinal manipulative therapy on thoracic spinal syndromes. Objective: To investigate the effectiveness of spinal manipulative therapy in the treatment of mechanical thoracic spine pain. Study Design: A single-blind, randomized, comparative, controlled pilot study. Setting: Technikon Natal Chiropractic Clinic in Durban, South Africa. Participants: Thirty subjects selected from the general population (from 16 to 60 years old) were randomly divided into two different treatment groups of 15 each. Methods: The objective measurements collected were the thoracic spine ranges of motion with the BROM II goniometer and pain threshold with an algometer. The subjective information required completion of the Oswestry Back Pain Disability Index, short-form McGill Pain Questionnaire, and Numerical Pain Rating Scale-101 Questionnaire by the patient. These 3 forms and objective measurements were collected before the first and final treatment and again at the 1-month follow-up consultation. The data gathered were then statistically analyzed with use of a 95% confidence level. The nonparametric Mann-Whitney U test and the Wilcoxon signed-rank test were used to compare intergroup and intragroup data, respectively. This was conducted at the α =.05 level of confidence. Further assessment of the data was conducted by use of power analysis. Interventions: The treatment group received thoracic spinal manipulation. The placebo group received nonfunctional ultrasound application only. The research project was carried out so that both groups received 6 treatments over a period of 2 to 3 weeks. A 1-month follow-up appointment was scheduled after the final treatment to assess the relative long-term benefits of the two different treatments. Results: Statistically significant results (P ≤.025) were noted for the percentage of pain experienced (Numerical Pain Rating Scale) and for right and left lateral flexion during intergroup comparison after the final treatment. The final treatment results were maintained at the 1-month follow-up consultation; however, there were no further statistically significant results. It was noted that the power was weak, so the probability of committing type II error (falsely accepting the null hypothesis) for the other measurements was high. The intragroup analysis showed statistically significant improvements in the group that received spinal manipulative therapy in both subjective and objective measurements between the first to final treatment and the first treatment to the 1-month follow-up consultation. The placebo group analysis showed a statistically significant improvement in sensory pain only (subjective measurement) between the first treatment and the final treatment. Conclusions: This pilot study suggests that spinal manipulative therapy has greater benefits than placebo treatment. The sample size was small, therefore the findings of this trial study should not be considered conclusive but rather should be used as a foundation for planning future studies. In further studies a larger sample size will be necessary to identify subtle changes in measurement parameters and to add to the validity of the results. (J Manipulative Physiol Ther 2001;24:394-401)