2015 ISAKOS Biennial Congress ePoster #2607

Hip Range of Motion Correlates with Kinematic Variables Related to Elbow Valgus Torque in Baseball Pitchers

Andrew Waligora, MD, Richmond, VA UNITED STATES
Trevor Lentz, PT, SCS, CSCS, Gainesville, FL UNITED STATES
Giorgio Zeppieri, MPT, SCS, CSCS, Gainesville, FL UNITED STATES
Bryan P. Conrad, PhD, Beaverton, OR UNITED STATES
Kevin Farmer, MD, Gainesville, FL UNITED STATES

University of Florida Department of Orthopaedics and Rehabilitation, Gainesville, Florida, USA

FDA Status Not Applicable

Summary: Increased dominant hip total arc and external rotation and non-dominant hip total arc and internal rotation may aid in the reduction of valgus elbow torque through their kinematic correlations.

Rate:

Abstract:

Background

There is a paucity of research devoted to understanding the link between lower and upper extremity mechanics in the pitching chain.

Hypotheses: Hip range of motion correlates with the kinematic variables previously found to be related to elbow valgus torque.

Study Design: Descriptive laboratory study.

Methods

Preseason dominant and non-dominant hip internal rotation (IR), external rotation (ER), and total arc (TA) were measured using a bubble inclinometer in seven (7) Division I collegiate pitchers. Each pitcher then performed a pitching analysis where full body kinematics were evaluated. The strength of the relationships between the kinematic variables previously established to be related to elbow valgus torque and hip range of motion were calculated using Pearson correlation coefficient.

Results

Earlier onset of maximal trunk angular velocity was found to be negatively-correlated with dominant TA (R2=0.71) and dominant ER (R2=0.65). A reduction in maximal shoulder external rotation was correlated with increased non-dominant TA (R2=0.70). Increased non-dominant IR values correlated with a more flexed elbow at ball release (R2=0.80)

Conclusion

Hip ROM correlates with several kinematic variables associated with valgus loads at the elbow. Increased dominant TA and ER and non-dominant TA and IR may aid in the reduction of valgus elbow torque through their kinematic correlations.

Clinical Relevance: If future data supports the findings of this study, a prehabilitation program may be implemented to modify specific components of dominant and non-dominant hip range of motion in order to prevent medial elbow injuries.