This multicenter observational study aimed to assess how pain reduction, induced by local anesthesia, affects the relative angular contributions of the shoulder girdle and trunk to the maximal angular performance during a semi-constrained overhead reach task in patients with ongoing shoulder pain. Twenty-nine individuals (age 59.0 SD 12.8 years;16-male) with symptomatic shoulders were administered corticosteroid and lidocaine injections by their attending orthopedic surgeon. Immediately before and after the injections, participants reached for a target on the ceiling ten times as high as possible while their pain levels, shoulder, and trunk movements were recorded. The analysis revealed that there was a significant reduction in pain following the injections. However, there were no significant differences in maximum shoulder and trunk inclination angles between the pre- and post-injection conditions. Notably, there were slight but statistically significant alterations in humeroscapular kinematics during the initial phase of arm elevation following the injections. In conclusion, acute pain relief following local anesthetics is not associated with immediate alterations in maximum shoulder girdle and trunk inclination angles during a semi-constrained overhead reach task in patients with ongoing shoulder pain. However, there are signs of small alterations in humeroscapular kinematics during the initial phase of arm elevation.

OBJECTIVE: To determine the construct validity, criterion validity, and responsiveness of measurement instruments evaluating scapular function. DESIGN: Systematic review of measurement properties. LITERATURE SEARCH: The MEDLINE, Embase, CINAHL, and SPORTDiscus databases were systematically searched from inception until March 2019. STUDY SELECTION CRITERIA: Studies published in Dutch, English, or German were included when they evaluated at least 1 of the measurement properties of interest. No restrictions were made regarding participants' health status. DATA SYNTHESIS: Two reviewers independently evaluated study quality using the COSMIN checklist and extracted and analyzed data. Quality of evidence was graded by measurement property for each distinctive type of measurement. RESULTS: Thirty-one measurement instruments in 14 studies were categorized into instruments to measure scapular posture and movement, and to assess scapular dyskinesis. Quality of evidence was at most moderate for 4 instruments with respect to criterion validity. Of these, criterion validity for instruments measuring scapular protraction/retraction posture and rotation angles up to 120° of thoracohumeral elevation was sufficient. Criterion validity for instruments measuring asymmetrical scapular posture, range of motion, and the lateral scapular slide test was insufficient. Quality of evidence for measurement properties of all other instruments was graded lower. CONCLUSION: There is currently insufficient evidence to recommend any instrument for the clinical examination of scapular function. Measurement instruments to assess scapular dyskinesis are prone to misinterpretation and should therefore not be used as such.