Thoracic spinal manipulation for musculoskeletal shoulder pain: Can an instructional set change patient expectation and outcome?

Abstract

Study designPlanned secondary analysis of a randomized clinical trial. ObjectivesTo examine: 1) patients' baseline expectations for treatment outcome of thoracic high velocity low amplitude thrust manipulations (HVLATM) to the thoracic spine for shoulder pain; 2) if the message conveyed by the clinician changed the patients' expectation; 3) any differences in outcome based on expectation independent of messaging.; and 4) any differences in outcome for those patients whose expectations significantly changed as a result of the messaging. BackgroundThoracic HVLATM may be an effective intervention for patients suffering from musculoskeletal shoulder pain. The role of expectation in the treatment effectiveness of this intervention has not been established. MethodsSubjects' expectations regarding the effectiveness of HVLATM on shoulder pain were recorded at baseline. This was reassessed immediately following the provision of positive or neutral instructional set. The subjects then received a thoracic or scapular HVLATM. The Shoulder Pain and Disability Index (SPADI) and the numeric pain rating scale (NPRS) were used as outcomes measures. ResultsThere was a 10 subject change (23%) in positive expectation that was statistically significant (p = 0.019) following a positive message. There was no statistically significant difference in pain and function when these subjects were compared to all other subjects. ConclusionAlthough patients' expectations of positive outcome significantly changed when providing a positive instructional set, these changes did not translate into clinically significant short term changes in shoulder pain and function.Level of Evidence: 1b.