Diagnostic Accuracy and Reliability of Sonographic Evaluation in Overhead Athletes with Shoulder Impingement Syndrome

Abstract

Introduction: Real Time Ultrasound (RTUS) is a suggested mean to assess and measure Acromiohumeral Distance (AHD), however due to limited researches, conclusive evidence of its use in overhead athletes with Shoulder Impingement Syndrome (SIS) is lacking. Aim: To determine intra-rater reliability, diagnostic property, relationship of isometric shoulder external rotation with AHD and variation in AHD at varied shoulder angles. Materials and Methods: In this case-control test-retest observational study, the total number of participants were 26. The participants were divided into three groups i.e., healthy individuals group, healthy athlete group and SIS athlete group as per their presenting features. The mean age of the athlete group was 22.15±2 years and the normal individual had a mean age of 21.9±1.5 years. They were tested for intra-rater test retest reliability at 0°, 45° and 60° shoulder abduction in SIS group, cut-off point AHD was determined for athletic groups and finally relationship of AHD and isometric shoulder External Rotation (ER) along with AHD differences was examined on dominant side across three groups. The test retest reliability measurement was measured using kappa statistics. One-way ANOVA was used to compare the three group differences. ROC analysis was used to estimate the sensitivity and specificity. Results: Intra class coefficient (ICC 2,1) score ranged from 0.96-0.97 (standard error of measurement=0.30-0.35 mm and minimum detectable change with 95% confidence=0.83-0.98 mm) for intra-rater reliability. ROC curve of dominant side concluded Area Under the Curve (AUC) to be 0.975 (p<0.001). The cut-off on dominant side of the athletic groups was reported to be 10.20 mm (sensitivity 0.90, p<0.001). Positive strong correlation were found between AHD and isometric ER strength on dominant side (r=0.924, p<0.05). Finally, at 0°, 45°and 60° dominant shoulder abduction revealed that acromiohumeral distance in SIS athletes were significantly different from other two groups (p<0.05). Conclusion: RTUS measurement of AHD has excellent test retest reliability, diagnostic accuracy and AHD and isometric external rotation are correlated in overhead athletes with SIS.

Keywords

• hand held dynamometer
• musculoskeletal disorder
• sonography