Preliminary Analysis of Closed Kinetic Chain Upper Extremity Stability Test Differences Between Healthy and Previously Injured/In-Pain Baseball Pitchers

Background: A comprehensive examination of the kinetic chain during an overhead athlete's upper extremity assessment, such as the dosed kinetic chain upper extremity stability test (CKCUEST), may help clinicians identify potential upper extremity dysfunction. Hypothesis: Body position observed on dominant and nondominant hand touch during a CKCUEST trial differs between players with previous injury/pain history compared with healthy counterparts. Study Design: Descriptive laboratory study. Level of Evidence: Level 5. Methods: Seventeen baseball pitchers were recruited to participate (18.03 +/- 2.01 years; 185.40 +/- 6.57 cm; 83.92 +/- 13.87 kg). A medical history questionnaire was used to separate participants into groups, either previous injury/pain or healthy. Kinematic and kinetic data were collected on the participants performing the CKCUEST with an electromagnetic tracking system. Kinematics were analyzed using a pair of 1-way multivariate analyses of variance (MANOVAs). Results: The MANOVA for nondominant hand touch in the CKCUEST revealed a significant difference in lumbopelvic-hip complex (LPHC) kinematics between previously injured/pain group and healthy group (Lambda = 0.37; F-4,F-12 = 5.12; P= 0.01). Conclusions: The previously injured/pain group displayed less pelvic axial rotation and dominant hip abduction during the nondominant touch indicating more LPHC stability during the nondominant touch. In conclusion, differences were observed in LPHC kinematics during the CKCUEST nondominant touch between a healthy and previously injured/pain group perhaps due to the increased awareness provided through rehabilitative programs for the previously injured/pain group.