Influence of Humeral Retrotorsion on Glenohumeral Range of Motion in Healthy Collegiate Softball Players.

The two groups were very uneven, 45 position players against 18 pitchers, and the authors' own power analysis put observed power for the between-group comparisons as low as 0.06 to 0.52. A real difference between pitchers and position players could easily have been missed. 58 of the 63 players threw right-handed. The authors say their findings cannot be applied to left-handed players until more data exist. Everyone was a college athlete who had finished growing, so this says nothing about younger throwers or about how these measurements change as a player develops. Players were measured at different points in the season and only the most recent measurement was used. Other research shows softball players' rotation changes over a season, and throwing activity just before testing was not controlled for. The examiners knew which arm was the throwing arm, and these are hand-held measurements taken at the first point of resistance or the first sign of shoulder blade movement. This is a single snapshot with no injury follow-up, so it cannot show that any of these measurements predicts or prevents shoulder or elbow problems.

The authors declare no conflicts of interest. No funding source is reported in the text supplied. The study was approved by the University of Texas Health Science Center at Houston institutional review board and all players signed an informed consent form.

This study measured range of motion in healthy players on one occasion and followed no one for injury, so it cannot show that measuring humeral retrotorsion, or treating the corrected deficit, prevents shoulder or elbow problems. The advice not to stretch a perceived internal rotation deficit comes from a single illustrative 16-year-old athlete, not from the 63 players studied.