In vivo measurements of glenohumeral distraction technique performed in three different joint positions.

Introduction: Distraction techniques are an important part of the manual approach in the glenohumeral joint; however, there is controversy regarding the initial joint position to maximize separation of joint surfaces.Objective: To identify, through an in vivo exploration, the behavior of the coracohumeral distance (CHD) during the application of a short lever arm grade III distraction technique on the humeral head, executed in three different glenohumeral positions (zero position (P0), rest position (RP) and 90º abduction position with maximum external rotation (ABD+ER)).Methods: 15 participants were selected. A physical therapist executed grade III distraction techniques in described joint positions. Ultrasound was used to visualize the differences in CHD. Statistical analysis included interclass correlation coefficients (ICC) and repeated measurements of ANOVA.Results: The range of ICC values was 0.740 and 0.948. The differences in CHD were 5.74 ± 0.51 mm, 3.97 ± 0.24 mm, and 0.64 ± 0.02 mm, for P0, RP and ABD+ER during application of distraction technique, respectively. There were differences between P0 and RP with ABD+ER (P < 0.001), and no differences between P0 and RP.Conclusion: Initial joint position of application influences the separation of the articular surfaces, being wider in the zero and rest positions.