Reliability of the sitting hand press-up test for identifying and quantifying the level of scapular medial border posterior displacement in overhead athletes.

BACKGROUND

The lack of proper scapular kinematics can limit the function of the entire shoulder complex.(1,3) Many forms of scapular dyskinesis have been proposed along with tests to measure for the position and motion associated with those positional and movement faults (2,4-6). While scapular internal rotation has been listed among the forms of scapular dyskinesis there has not been a reliable test documented in the literature that examines this motion. The purpose of this study was to determine whether an innovative scapular medial border posterior displacement measurement device has adequate inter-rater and intra-rater reliability when used at rest and during the sitting hand press up test.

METHODS

16 male Division III baseball players free of upper limb injury for the previous 12 months participated in the study. Posterior scapular displacement measures were taken on each subject in a resting static posture and while performing a sitting hand press up test. Subjects were tested twice within 24 hours by two separate examiners. Intraclass correlation coefficients (ICC) were calculated to determine intra-rater and inter-rater reliability.

RESULTS

The intra-rater reliability for rater 1 was .97 (95% confidence interval [CI]= .91-.98), for the rest position and .95 (95% CI= .86-.98) for the sitting hand press-up position. Intra-rater reliability for rater 2 was .99 (95% CI= .97-.99) for the rest position and .98 (95% CI=. 95-.99) for the sitting hand press-up position. The ICCs for inter-rater reliability of the scapular medial border posterior displacement measurement in at the rest position and the sitting hand press-up position were .89 (95% CI= .81-.96) and .89 (95% CI= .80-.96) respectively.

CONCLUSIONS

The findings of this study indicate that the measurement of medial border posterior displacement using this device demonstrates good to excellent inter-rater and intra-rater reliability.