Shoulder functional performance status of Minor League professional baseball pitchers

Abstract

Background and hypothesis: The Overhead Shoulder and Elbow Score (Kerlan-Jobe Orthopaedic Clinic [KJOC] score) among healthy or uninjured professional baseball pitchers is lacking. We hypothesized that shoulder function and performance status measured by the KJOC score among active Minor League professional baseball pitchers were high at pre-participation and that the pitchers who had not been previously treated for a shoulder injury and were playing without arm trouble had significantly higher KJOC scores than their counterparts.

Methods: In this cross-sectional survey, data on pre-participation KJOC scores, along with other study measures, were collected from a cohort of Minor League professional baseball pitchers. Generalized estimating equations with a Poisson distribution were used for analysis.

Results: A total of 366 Minor League professional pitchers were included, with a mean KJOC score of 92.8 points (SD, 12.1 points), suggesting that participating pitchers' shoulder function and performance were high. Participating pitchers who had not received treatment for a shoulder injury had significantly higher KJOC scores than those who had received treatment, either surgical or nonsurgical (β = 0.0238, P = .0495). In addition, pitchers who were not currently injured, were playing without arm trouble, or had not missed games in the past 12 months because of a shoulder injury also had statistically significantly higher KJOC scores than their counterparts.

Conclusion: This study provides an empirical profile of the KJOC score for a large sample of active Minor League professional baseball pitchers and identifies risk factors associated with decreased KJOC scores.

Keywords: Baseball; KJOC score; professional pitchers; shoulder.