CORRELATION BETWEEN THE KERLAN-JOBE ORTHOPEDIC CLINIC SCREEN AND SUBACROMIAL IMPINGEMENT TEST-ITEM CLUSTER IN COLLEGIATE BASEBALL PITCHERS: A PILOT STUDY

Background

Shoulder injuries in baseball related to throwing account for 60% of all baseball injuries and 75% of those throwing injuries occur in pitchers. Impingement is the beginning of a continuum of rotator cuff pathology that can result in pain and disability in pitchers. Identification of self-reported measures and clinical tests that can indicate early pathology of shoulder impingement is needed for overhead athletes. Early identification of shoulder impingement is important to the long-term health and function of these athletes.

Hypothesis/Purpose

The purpose of this study was to determine if a correlation exists between self-reported pain and disability using the Kerlan-Jobe Orthopedic Clinic (KJOC) score and the Park Test-Item Cluster (TIC) for subacromial impingement in college baseball pitchers. The research hypotheses are that there will be a correlation 1) between the KJOC score and the TIC by Park and 2) between the KJOC and the Hawkins-Kennedy impingement, the painful arc, and the infraspinatus muscle strength tests individually.

Design

Cross-sectional pilot study.

Methods

Twenty-one collegiate baseball pitchers completed the KJOC and then were tested using the Park test-item cluster.

Data Analysis

Kruskal-Wallis was used to test the relationship of individual demographics with KJOC scores. Spearman rho correlation was used to determine if the number of positive clinical tests in the Park TIC or with the individual tests within the TIC correlated with scores on the KJOC.

Results

No significant relationships between KJOC scores and demographics were found. A significant moderate-to-good relationship was found between the painful arc test and the KJOC (r = -.601, p = 0.00) and a significant fair correlation was found between the number of positive tests within the Park TIC and KJOC (r = -.426, p = 0.05). No significant relationships were found between the Hawkins-Kennedy and KJOC (r = -.348, p = 0.12) or between the infraspinatus strength test and KJOC (r = -.040, p = 0.86).

Conclusion

The correlations between the painful arc test and the number of positive impingement tests with the composite score on the KJOC suggests a relationship between these two outcome measures, shoulder irritability, and decreased function in collegiate baseball pitchers. Of the three tests included in the Park TIC, the painful arc test was the only one with an independent significant correlation to the KJOC. The combination of impairment-specific cluster testing and an activity-focused self-assessment tool could be utilized to identify potential pathology and alert the medical professional that assessment and intervention are necessary.

Level of Evidence

Level 2 (Diagnosis).